Alesis QuadraverbPlus Schematic

Download

Page 1

Alesis QuadraVerb Service Manual

Revision 1.00

6/28/94

Alesis QuadraVerb Service Manual------ 1

Page 2

PREFACE

This document is intended to assist the service technician in the operation, maintenance and repair of the QuadraVerb digital effects processor. Together with the QuadraVerb Reference Manual, this document provides a complete description of the functionality and serviceability of the QuadraVerb. Any comments or suggestions you may have pertaining to the document are welcome and encouraged.

READ THIS!

In addition to any purchase price that Alesis may charge as consideration for Alesis

selling or otherwise transferring this service manual (“Manual”) to you, if you are not a service and repair facility (“Service Center”) authorized by Alesis in writing to be an

authorized Service Center, Alesis sells or transfers the Manual to you on the following terms and conditions:

Only Service Centers authorized by Alesis in writing are authorized to perform service and repairs covered by an Alesis warranty (if any), and transfer of the Manual to you does not authorize you to be an authorized Service Center. Therefore, if you perform,

or if the Manual is used to perform, any service or repairs on any Alesis product or part thereof, any and all warranties of Alesis as to that product and any service contract with Alesis for that product shall be voided and shall no longer apply for such product, even if your services or repairs were done in accordance with the Manual.

All service or repairs done by you or with reference to the Manual shall be solely your responsibility, and Alesis shall have no liability for any such repairs or service work. All

such service or repairs are performed at the sole risk of the person performing the service or repairs. You agree that all such work will be performed in a competent,

professional and safe manner at all times and to indemnify and fully hold Alesis and its successors and assigns harmless in the event of any failure to so perform.

Your purchase of the Manual shall be for your own ultimate use and shall not be for purposes of resale or other transfer.

As the owner of the copyright to the Manual, Alesis does not give you the right to copy the Manual, and you agree not to copy the Manual without the written authorization of Alesis. Alesis has no obligation to provide to you any correction of, or supplement to, the Manual, or any new or superseding version thereof.

Alesis shall have the right to refuse to sell or otherwise transfer repair parts or materials to you in its sole discretion. You shall not use, sell or otherwise transfer spare or replacement parts supplied by Alesis to you (i) to repair or be used in products manufactured for or by third parties or (ii) to any third parties for any purpose.

You shall not make any warranties or guarantees with respect to the products of Alesis or the use thereof on behalf of Alesis or in your own name.

The foregoing describes the entire understanding related to sale or transfer of the Manual to you, and no other terms shall apply unless in a writing signed by an authorized representative of Alesis.

Alesis QuadraVerb Service Manual------ 2

Page 3

WARNINGS

CAUTION

RISK OF ELECTRIC SHOCK

DO NOT OPEN

TO REDUCE THE RISK OF ELECTRIC SHOCK OR FIRE, DO NOT EXPOSE THIS PRODUCT

TO WATER OR MOISTURE.

The arrowhead symbol on a lightning flash inside a triangle is intended to alert the user to the presence of un-insulated "dangerous voltage" within the enclosed product which may be of sufficient magnitude to constitute a risk of electric shock to persons.

The exclamation point inside a triangle is intended to alert the user to the presence of important operating, maintenance and servicing instructions in the literature which accompanies the product.

CAUTION

Danger of explosion if battery is incorrectly replaced.

Replace only with the same type or equivalent type

recommended by the equipment manufacturer.

Battery Manufacturer: Tadiran

Type: TL-5101

Rating 3.6V

REPAIR BY ANY PERSON OR ENTITY OTHER THAN AN AUTHORIZED ALESIS SERVICE

CENTER WILL VOID THE ALESIS WARRANTY.

PROVISION OF THIS MANUAL DOES NOT AUTHORIZE THE RECIPIENT TO COMPETE

WITH ANY ALESIS DISTRIBUTOR OR AUTHORIZED REPAIR SERVICE CENTER IN THE

PROVISION OF REPAIR SERVICES OR TO BE OR MAKE REPAIRS AS AN AUTHORIZED

SERVICE CENTER.

ALL REPAIRS DONE BY ANY ENTITY OTHER THAN AN AUTHORIZED ALESIS SERVICE

CENTER SHALL BE SOLELY THE RESPONSIBILITY OF THAT ENTITY, AND ALESIS

SHALL HAVE NO LIABILITY TO THAT ENTITY OR TO ANY OTHER PARTY FOR ANY

REPAIRS BY THAT ENTITY.

Alesis QuadraVerb Service Manual------ 3

Page 4

SAFETY SUGGESTIONS

Carefully read the applicable items of the operating instructions and these safety suggestions before using this product. Use extra care to follow the warnings written on the product itself and in the operating instructions. Keep the operating instructions and safety suggestions for reference in the future.

1. Power Source. The product should only be connected to a power supply which is described either in the operating instructions or in markings on the product.

2. Power Cord Protection. AC power supply cords should be placed such that no one is likely to step on the cords and such that nothing will be placed on or against them.

3. Grounding the Plug. This product has a 3-wire grounding type of plug (a plug with a grounding pin) for safety purposes. This plug can only be used in a grounding power outlet. If the plug does not insert into the outlet you are using, the outlet probably is not a grounding type of power outlet. Contact your electrician to replace the obsolete outlet with a grounding type of outlet instead of defeating the safety feature of the grounding type of plug.

4. Periods of Non-use. If the product is not used for any significant period of time, the product's AC power supply cord should be unplugged from the AC outlet.

5. Foreign Objects and Liquids. Take care not to allow liquids to spill or objects to fall into any openings of the product.

6. Water or Moisture. The product should not be used near any water or in moisture.

7. Heat. Do not place the product near heat sources such as stoves, heat registers, radiators or other heat producing equipment.

8. Ventilation. When installing the product, make sure that the product has adequate ventilation. Improperly ventilating the product may cause overheating, which may damage the product.

9. Mounting. The product should only be used with a rack which the manufacturer recommends. The combination of the product and rack should be moved carefully. Quick movements, excessive force or uneven surfaces may overturn the combination which may damage the product and rack combination.

10. Cleaning. The product should only be cleaned as the manufacturer recommends.

11. Service. The user should only attempt the limited service or upkeep specifically described in the operating instructions for the user. For any other service required, the product should be taken to an authorized service center as described in the operating instructions.

12. Damage to the Product. Qualified service personnel should service the unit in certain situations including without limitation when:

a. Liquid has spilled or objects have fallen into the product, b. The product is exposed to water or excessive moisture, c. The AC power supply plug or cord is damaged, d. The product shows an inappropriate change in performance or does not operate normally, or e. The enclosure of the product has been damaged.

Alesis QuadraVerb Service Manual------ 4

Page 5

General Troubleshooting

While this manual assumes that the reader has a fundamental understanding of electronics and basic troubleshooting techniques, a review of some of the techniques used by our staff may help.

1. Visual Inspection - A short visual inspection of the unit under test will often yield results without the need of complex signal analysis (burnt, or loose components are a dead giveaway).

2. Self Test - Alesis products that utilize microprocessor control contain built in test software which exercises many of the units' primary circuit functions. Self test should always be done following any repair to ensure basic functionality.

3. Environmental Testing - Applying heat and cold (heat gun/freeze spray) will often reveal thermally intermittent components (Clock crystals, I.C.s, and capacitors are particularly prone to this type of failure).

4. Burn in Testing - Leaving a unit running overnight often reveals intermittent failures such as capacitors that begin to leak excess current after a significant amount of time.

5. Cable Checks - Wiggling cables can reveal intermittent failures such as loose cables or poorly soldered headers. Remember to check power supply cables as well.

6. Flexing the PC Board - Poor solder joints and broken traces can often be found by pressing the PC Board in various places.

7. Tapping Componants - Somtimes tapping on a component (particularly crystals) will cause it to fail.

8. Power Down/up - Turning the unit off and back on rapidly several times may reveal odd reset and/or power supply failures.

9. Reset Threshold - A Variac (variable transformer) can be used to check reset threshold levels. This can be particularly useful in helping customers with low line problems.

10. Compressors - Using a compressor/limiter is often helpful when attempting to solve low level noise problems, as well as assisting with DAC adjustments.

11. Sweep Tests - Sweep generators are very useful in checking the frequency response envelopes of antialiasing filters.

12. Piggybacking - Piggybacking I.C.s is particularly useful when troubleshooting large sections of logic. This is especially true when working with older units.

Alesis QuadraVerb Service Manual------ 5

Page 6

Table of Contents

PREFACE .................................................................................................................................... ii

READ THIS! ................................................................................................................................. ii

WARNINGS ................................................................................................................................. iii

SAFETY SUGGESTIONS ........................................................................................................... iv

General Troubleshooting .............................................................................................................. v

1.0 QuadraVerb General Description ........................................................................................... 1

2.0 Power Supply ......................................................................................................................... 1

2.1 Battery Backup .......................................................................................................... 2

3.0 Analog Signal Paths ............................................................................................................... 2

3.1 Anti-Aliasing Filters .................................................................................................... 3

3.2 Successive Approximation ........................................................................................ 3

4.0 Digital Signal Paths ................................................................................................................ 4

4.1 80C31 Micro Controller Circuit .................................................................................. 4

4.2 Reset ......................................................................................................................... 4

4.3 Memory Mapped I/O .................................................................................................. 5

4.4 Analog Input and the 8031 ........................................................................................ 5

4.5 DASP 24 ASIC .......................................................................................................... 5

5.0 Test Procedures ..................................................................................................................... 6

6.0 Adjustments............................................................................................................................ 6

7.0 Updates and Revisions .......................................................................................................... 6

7.1 D15 ............................................................................................................................ 7

7.2 Header Capacitor ...................................................................................................... 7

7.3 R66 ............................................................................................................................ 7

7.4 SRAM Supply ............................................................................................................ 7

7.5 Battery Ground .......................................................................................................... 7

7.6 Cables ....................................................................................................................... 7

7.5 LCD Contrast ............................................................................................................. 7

7.6 LCD Cable Header .................................................................................................... 7

7.7 Wet VCA Removal .................................................................................................... 7

7.8 DAC Adjustment Installation...................................................................................... 8

7.9 Increasing Output Gain ............................................................................................. 8

7.10 QV I/P Filter Kit Installation ..................................................................................... 8

8.0 Helpful Hints & Common Solutions ........................................................................................ 12

9.0 Schematics ............................................................................................................................. 14

10.0 Software History ................................................................................................................... 16

11.0 Quadraverb Plus MIDI Implementation/System Exclusive ................................................... 18

12.0 Quadraverb Service Parts List ............................................................................................. 34

Index ............................................................................................................................................. 37

Service Manual History ................................................................................................................. 39

Alesis QuadraVerb Service Manual------ 6

Page 7

1.0 QuadraVerb General Description

Diagram 1

The QuadraVerb, and other digital reverbs, achieve their results by slicing analog signals into segments, and then converting them to a numeric value, corresponding to the amplitude of the signal at that particular instant. These values are then mathematically manipulated, and stored at various locations in a memory "loop" for eventual playback. By varying the placement and amplitude of incoming samples, discrete time delays are achieved. When mixed together, and converted back into analog, these delays simulate the reflections associated with natural reverbs, and delays, as well as non natural effects such as reverse reverbs, and gated reverbs. The added capabilities of an 80C31 micro controller allow for user manipulation and storage of algorithm parameters, as well as effects such as chorus, and flange, that require real-time manipulation of algorithms. Please note that there are several different main PCB revisions, so differences will be noticed from unit to unit.

2.0 Power Supply

The power supply begins with the 9 Volt A.C., adapter. Input from J6 is R.F. filtered by C31 before on/off switch S1. From there it is split for the +12V, -12V, and +5V rails. The +12V rail consists of a voltage doubler (C22, C24, and D13, D14), a 7812 regulator (U31), and filter caps (C3, C14). The -12V rail is a "mirror" of the +12V rail, consisting of voltage doubler (C21, C23, and D10, D11), a 7912 regulator, and filter capacitors (C7, and C15). The +5V rail consists of a rectifier diode (D12), filter capacitors (C17-C20), a 7805 regulator, and a multitude of 0.1uF bypass capacitors. Note that the raw +10V line used by the microprocessor reset, and the SRAM power supply (when retrofitted), and is located at the input to the 7805 regulator.

2.1 Battery Backup

Alesis QuadraVerb Service Manual------

Page 8

Battery backup is actually more complicated than it might first appear, as it depends on a good system reset (see section 4.2 for details) in order to function properly. The actual backup circuit consists of a battery (3V - 3.6V Lithium), a 10K resistor (R61) for checking standby current (see below), a "steering" diode (D4), a filter capacitor (C16), and a transistor/resistor/diode combination that acts as a steering diode. This combination may be missing on older board revisions, and must be installed (see section 7.0) to prevent data corruption due to a significant difference between Vcc, and the amplitude of the data buss.

SRAM standby current should always be checked. While the unit is off, check the voltage across R61. If the voltage is higher than 80mV (specification, although a 1 to 20mV range is more normal) then a problem exists. Usually it indicates a bad (or simply wrong) SRAM, or a short, somewhere along the MEM PWR line. Note, that for a short time, Sony 58256-PM (high power) SRAMs were being installed at the factory, and should be replaced with low power versions (58256LP) when found (see section 7.0.), in order to eliminate excess battery drain. We are currently using Hitachi 62256ALPs as replacements.

CAUTION:Danger of explosion if battery is incorrectly replaced. Replace only with the same type or

equivalent type recommended by the equipment manufacturer. Battery Manufacturer: Tadiran Type: TL-5101 Rating 3.6V

3.0 Analog Signal Paths

The inputs (stereo) have their impedances fixed at 1M by R3 and R6. While operating the unit monauraly (left input only) the input impedance fixed at 500K (R3, and R6, in parallel). From there, the inputs are buffered by U1, A.C. coupled (C1, C2), and passed through a variable (input level), X10, gain stage. The stereo signal is then sent to the outputs via the dry VCA (U5). It is also summed to mono (Via R17, R18) before being passed along to the anti-aliasing filter (discussed later), and the LED control circuit. The LED circuit consists of a rectifier (U4, D2), a fairly standard comparator ladder (U7 & associated resistors), and a one shot multivibrator (U24, D3, etc.) to provide a time constant so that ASIC math overflow conditions stay highly visible.

The summed stereo signal, after passing through the anti-aliasing filter, continues into the input sample and hold circuit. The input sample and hold circuit consists of 1/3 of the 4053 analog switch (U9), the input sample cap (C38), a buffer amplifier (U3), and a comparator (U8).

The signal beyond this point is purely digital, until the DAC output cycle of the DASP 24. At the appropriate time, the DAC will output the processed left, and right signals. This action is coordinated with the two output sample and hold circuits (2/3 U9, 2 op amps of U3, C39, C40), so that each receives the correct, separate signal for stereo output. After passing through low pass filters (2 op amps of U4, Misc. Resistors & Capacitors), the signals are summed with the output of the dry VCAs (note that on older board revisions, the signal will pass through the wet VCA [U6] first). The signals then pass through another filter section (U2, etc.), to the output potentiometer. From here, they pass through unity gain amps (U2, etc.), and finally through impedance fixing resistors R9, and R14, to the output jacks. Note that some incompatibilities have been encountered when using the QuadraVerb with some particular amplifier effects loops. If the customer is experiencing level drops when using the unit in such a setup, it is possible to adjust the output stage gain to accommodate the amplifier (see section 7.11).

Alesis QuadraVerb Service Manual------

Page 9

3.1 Anti-Aliasing Filters

Diagram 2

Diagram 3

Different QuadraVerb PCB revisions utilize 3 different types anti-aliasing filters, to eliminate Nyquist errors. The 1st is a four pole active filter, and will be seen on the oldest PCB revisions (A through E). If problems occur when using these older board revisions with digital synth's, and some "hot" guitar pickups, it will be necessary to upgrade this filter to a type 2. The type 2 filter is a six pole version of the active filter, and includes a preemphasis curve. It will only be seen on older board rev.s that have been upgraded. The 3rd type of filter is the LC block filter. This single component filter is seen on revision F, and later, boards. It eliminates the need for active circuitry, as well as facilitating easier servicing.

3.2 Successive Approximation

Successive approximation is a heuristic approach to the process of analog to digital conversion. The idea is to divide the process into short, manageable sections. Each significant binary weight (starting with the Most Significant Bit) is taken in turn, thus requiring only 16 comparisons to achieve a final value.

The process begins with the input "sample and hold circuit". 1/3 of the 4053 (U9) is turned on, allowing the input sample capacitor (C38) to charge [or discharge] to the level of the current input signal. When the switch is turned off, the capacitor will hold that level indefinitely [barring internal leakage ]. At this point, the SAR (Successive Approximation Register-part of the DASP 24 ASIC) will take over. Starting with the MSB, the SAR will set the bit, and compare the output of the DAC, to the level of the input sample capacitor (via comparator U8). The results of the

Alesis QuadraVerb Service Manual------

Page 10

comparison are stored, and the next most significant bit is compared. This process continues until a value is found for all 16 bits, and the data is ready for further processing by the ASIC (note that the value is in two's compliment math). In order to view these signals properly on the scope, it will be necessary to use an external scope sync (use U9, pin 9 as the sync source). Diagrams 2, and 3, show the DAC output during a couple of SAR cycles, with no input, and full input.

4.0 Digital Signal Paths

Note that later board revisions incorporate a "split" data buss. In other words, most "external" data lines are separated from the main buss via a de coupling network (R35, R84-90, C28-30, C3537, C42, C44). This is to provide better RF suppression, however, it can also cause some unique situations. Normal signals on this "secondary" buss, will appear extremely distorted (for digital signals), and sometimes lead a technician to believe that there may be a bad latch, even though all components on the buss are functioning properly. Conversely, a bad latch can load the buss in such a way, that bad timing occurs, corrupting data even though the signals appear "normal".

4.1 80C31 Micro Controller Circuit

The 80C31 MPU controls all "user interface" functions of the QuadraVerb. These functions range from handling the front panel buttons, to continuously updating algorithm information to the DASP 24 ASIC. Note that the 8031 data buss serves a dual purpose. This buss multiplexes between low order addresses (1st 8 bits), and data. Latch U20 is used to hold the low order address half, during 8031 read and write cycles. The EPROM (U19) is used to hold both program information, and algorithm data. The SRAM (U18) holds system variables, as well as user preset data. The 12MHz 8031 clock is derived from the 24MHz clock (Z1) via a divide by 2 counter (1/2 U24). MIDI I/O is handled through the 8031's built in RXD (Read Serial Data), and TXD (Transmit Serial Data) ports. Front panel keypad decoding is handled through a combination of memory mapped I/O (see section

4.3), and the 8031's built in I/O ports.

4.2 Reset

The 8031 reset circuit is perhaps the single most important circuit in the QuadraVerb. When this circuit is functioning incorrectly, problems ranging from loss of battery backup, to a complete lock-up of the machine, can occur. A thorough knowledge of the operation of this circuit will greatly facilitate troubleshooting this unit.

This circuit uses the differential between raw +10V, and regulated +5V, to generate the required signals for system reset. This is necessary due to fact that the system MUST be in a reset state while powering down, otherwise, random noise on the 8031 data, and address, busses could corrupt SRAM data, and destroy any hope that the battery backup will work. C25 acts as a long time constant, to ensure that reset line is enabled long enough for proper system reset. D7 acts as a quick discharge path for C25, ensuring that resets will occur, even if the unit is turned off, and then rapidly back on. R16, R60, R58, and D15, work together as a voltage divider to the base of Q3, and is designed so that transistor Q3 will turn on when the raw +10V supply is roughly 7V. This is to ensure that reset does not occur until after the +5V regulator is fully functioning (i.e. +5V rail is solid). If reset occurs too early, noise on the +5V rail can cause data corruption. Pull-up resistor R59 holds the input of the inverter (U25, pins 13, 12) high, until Q3 turns on, pulling the input low. When this occurs, the output of 2nd inverter (U25 pins 10, 11) will also go low, slowly, due to the time constant of R95, and C32. The power off reset is similar. When the +10V raw supply sinks below 7V, Q3 is turned off, allowing the input of the inverter (U25, pins 13,12) to pull high (via pull-up R59), and thus the same for the output of the 2nd inverter (U25, pins 10,11). Also note the tap between the two inverters, running to the input of AND gate U26 (pins 1,2, and 3). This prevents access to SRAM functions while in the reset condition, thus preventing data corruption.

Alesis QuadraVerb Service Manual------

Page 11

4.3 Memory Mapped I/O

The QuadraVerb (and many other Alesis products) utilizes a memory mapped I/O system in order to deal with the wide variety of functions that the 8031 needs to access. During the write cycle of the 8031, data on the 8031 data buss is made available to a series of latches. When the WRN (pin 16) signal of the 8031 is enabled, and A15 (address's most significant bit) is active, the 3 to 8 line demux (U23) is used to decode the 3 least significant address lines, and send a strobe to the clock input of one of these latches. Consequently, data can be "stored" into a latch simply by writing a value into a memory location. Note that, in this scenario, data is write only. All input functions to the 8031 are handled through the 8031's built in I/O ports.

4.4 Analog Input and the 8031

While output from the 8031 can be handled simply using memory mapped I/O, and binary weighted networks, analog input to the 8031 is a bit trickier. The method used in the QuadraVerb, is to examine the time it takes a constantly charging capacitor to reach the level of the input signal. The majority of op amp U22 is used to accomplish this. We will examine the audio threshold input. The principle will also apply to the piezo (Z2) value input circuit.

The process begins with the 8031 temporarily turning on Q2 (via mapped I/O latch U29). After turning Q2 back off, the 8031 begins counting. While the 8031 is counting, C56 charges through R51. This signal is compared to the incoming rectified analog signal (from the LED control circuit) by U22 (pins 5, 6, and 7). When the charge on C56 reaches the level of the input signal, U22 pin 7 will change states, informing the 8031 via input port P3.2. The 8031 ceases counting, and can use the "count" value as a "level" value for processing.

4.5 DASP 24 ASIC

The DASP (Digital Audio Signal Processor) 24 ASIC (Application Specific Integrated Circuit), is a complex, VLSI IC designed specifically to handle the specialized needs of digital effects processing. Obviously, a full discussion of this device is beyond the scope of this manual, however, a brief introduction to the device is definitely in order.

The DASP 24 contains a SAR (Successive Approximation Register), a writable control store (internal memory for algorithm storage), and a RISC (Reduced Instruction Set Computer) for use as an Arithmetic Logic Unit. Memory management hardware, and a variety of control hardware round out the package. Some important control signals are outlined below.

Alesis QuadraVerb Service Manual------

Page 12

Signal Pin Function RAS 3 - DRAM Row Address Strobe

CAS 4 - DRAM Column Address Strobe MDE 5 -DRAM output enable. STB 40 - Instructs DASP 24 to accept 8031 DATA CLK 42 - 24MHz clock from Z1 RST 53 - RESET INH 54 - Controls sample and hold circuit timing. SNHOUT 0 55 " SNHOUT 1 56 " LSTMSB 57 - This signal indicates the last state of the MSB (the sign bit in two's complement math). This

signal, in conjunction with R36, R47, R48, and C13, is used to bias the incoming analog signal slightly positive, or negative, depending on the result of the last DAC cycle (i.e. if the last DAC cycle started off with a negative value, LSTMSB will be 1, causing the input to the sample and hold circuit to pull slightly positive. On the next cycle, the reverse will occur). This reduces any audio pop during the attack portion of the input signal, and allows for a faster response to small signals.

ADC 74 - A/D comparison input. OVFLO 75 - This signal indicates a math overflow condition, and consequently turns on the clip LED circuit. WR 84 - DRAM write enable

5.0 Test Procedures

If possible, user data should be saved (a DataDisk is recommended) prior to any servicing. This, of course, may not always be possible (i.e. dead power supply, bad reset signal, corrupt data, etc.). Saving user data may also be accomplished after unit functionality is restored (i.e. power supply, or reset line, is repaired), and prior to further servicing, and testing. The unit should always be reinitialized (power unit up while holding "BYPASS" and "PROG" buttons down) after changing the EPROM, SRAM, or any part of the battery backup. To perform the QuadraVerb's self diagnostics connect a MIDI cable between MIDI in, and MIDI out. Power up the unit while holding the "BYPASS", and "CONFIG", buttons down. The unit will then test ROM, RAM, Button LEDs, MIDI, and the clip LED. In the event of a ROM, RAM, or MIDI failure, the unit will stop, and the display will show "ERROR IN {COMPONENT}".

6.0 Adjustments

There are no adjustments necessary, unless a DAC adjust trimpot has been installed at the time of service. The easiest way to adjust the DAC is to use a fast lezlie program, with no signal input. With the lezlie output turned fully up, adjust the trimpot for a minimum noise floor. (See section 7.0 for installation instructions.)

7.0 Updates and Revisions

Note that these items may not apply to all board revisions. Where updates are board revision specific, the bold type characters at the beginning of the note indicates applicable board revision designations.

7.1 D15

A-E Zener diode (D15) at bottom, right-hand corner of board (in reset circuit) should be a

metal zener and NOT a glass zener. The glass types have been found to be somewhat unreliable.

Alesis QuadraVerb Service Manual------

Page 13

7.2 Header Capacitor

Diagram 4

Diagram 5

A-E There should be a .1uF cap added between pins 1 and 3 of LED cable header J2. This prevents possible oscillation at power up.

7.3 R66

R66, next to opto isolator (U30), should be 10K. If it is 47K, add a 12K or 13K resistor in parallel to make it 10K. This decreases the opto-isolators input threshold, for improved MIDI input performance.

7.4 SRAM Supply

SRAM Supply adjustment (See diagrams 4 and 5). This supplies a solid 5V to the SRAM, preventing input data from being higher in amplitude than the supply voltage, which can cause data corruption.

7.5 Battery Ground

Check battery GND connection and resolder if necessary. Cold solder joints, can exist there, resulting in memory loss and crashing.

7.6 Cables

Check all connector cables are firmly seated. In some cases, they can come 1/2 way off.

7.5 LCD Contrast

Check LCD contrast - if contrast is too dark then short D6.

7.6 LCD Cable Header

Hot glue the LCD cable header to LCD, to prevent it from falling off in transit.

7.7 Wet VCA Removal

A-E Software version 1.07 or above It may be necessary to bypass the wet VCA to decrease the noise floor. To do this, remove U6. Add jumpers across C11, C12, from U6 pin 1 to pin 3, and from pin 5 to pin 7 (see diagram 7).*

Alesis QuadraVerb Service Manual------

Page 14

7.8 DAC Adjustment Installation

It may also be necessary to install a DAC adjust trimpot to decrease DAC noise. The components required are a 250K trimpot (R43), 2 200K resistors (R20 and R44), and a 1M resistor (R45). See diagram 8 for locations.*

7.9 Increasing Output Gain

It may be necessary to change the gain of the output stage to accommodate the users of some amplifier effects loops. To do this, change R11, and R12, to a value between 4.7K and 10K (the larger the value, the higher the gain).*

* - The application of these items are left to the discretion of the technician.

7.10 QV I/P Filter Kit Installation

The following update enhances the input filter of the Quadraverb by increasing the number of filter poles from 4 to 6. This gives a corresponding increase in the filter rolloff rate, and eliminates problems encountered when using the QV with high bandwidth samplers such as the Ensoniq ESQ1, the Roland D-50, or the EMU Proteus.

Here is a list of components that will be changed or added:

Component New Value Added Diagram * R16 9.1K ------- 7 R19 4.3K ------- 7 R23 680R ------- 7 R24 2.4K ------- 7 R25 27K ------- 7 * R26 33K ------- 7 * RA ------- 3.6K 7 * RB ------- 1.3K 7 R42a ------- 750R 8

C35 47pF ------- 7 C36 .033uF ------- 7 C42 1500pF ------- 7 C43 .033uF ------- 7 C44 100pF ------- 7 * CA ------- 3300pF 7 * CB ------- .01uF 7

**R20 ------- 200K 8 **R44 ------- 200K 8 **R45 ------- 1M 8 **R43 ------- 250Ktrm 8 * Requires special installation, see below.

** Recommended, but not necessary.

Alesis QuadraVerb Service Manual------

Page 15

For the purposes of a common orientation, we will assume that you are looking at the component side of the board, with the front panel facing you. Refer to Diagram 7 for individual component orientation.

Solder one leg of R16 to the left feed through of the original R16 (let the other leg stand straight up). Solder one leg of RB to the right feed through of the original R16. Scrape the solder mask off of the ground plane under the original R16, then solder one leg of CB to the exposed ground plane (again, leaving the other leg sticking up). Twist the three free-standing leads together to form a "teepee", and solder them together. Repeat this procedure with R26, RA, and CA. (R26 on the left, RA on the right. The ground plane between R26 and R27 is the easiest place to attach CA.)

Solder R42a in parallel with R42 (if this is forgotten, the "de-emphasis" will not be correct, and the unit will sound "shrill").

It is recommended (but not absolutely necessary) to install R20 (200K), R44 (200K), R45 (1M), and the 250K trimpot (R43). (When it comes time to adjust the DAC, use a fast LEZLIE program, and adjust the trimpot for minimum output noise with no input signal and maximum output level.)

Replace the rest of the components per the above value change list. To test, hook the unit up to a signal source, and amplifier. Adjust the DAC trimpot. Audibly,

the unit should not sound "shrill" (too much high end), or "muddy" (too little high end). Highs should sound clean up to about 18KHz before rolling off. If a signal/sweep generator is available, the frequency response can be specifically compared to the provided Bode plot (diagram 9). Use the right input channel. Adjust the input level to the QV to about 1Vp-p, sweeping from 20Hz to 25KHz. Observe the filters output at U3 pin 7. Any large deviations from the plot indicate a problem and should be troubleshot.

Alesis QuadraVerb Service Manual------

Diagram 6

Page 16

Alesis QuadraVerb Service Manual------

Diagram 7

Page 17

Diagram 8

Alesis QuadraVerb Service Manual------

Diagram 9

Page 18

8.0 Helpful Hints & Common Solutions

No Power, No Lights, No Life

Bad Ram Cap. (We have found that the blue, monoblock, ram caps are unreliable, and have since switched to ceramic disk only.

Examine the PCB for any burnt, or hot, ram caps, and replace, if necessary.

Blown DASP 24 ASIC.

If this IC is extremely hot, to the touch, then it is faulty.

Bad +5V rectifier diode (D12)

The cathode should read roughly 10V (with some ripple). It has been noticed that 1N4001 seem to have problems, and since then have started using 1N4003 diodes exclusively.

Unit lights up, but there is no LCD Display. Unit locks up.

Bad Reset circuit.

Check reset (U21 pin 9), both during power up, and down. Troubleshoot if necessary.

Bad 80C31.

Replace, and re-test.

Bad 24MHz Crystal (Z1).

Some crystals are shock sensitive. Tapping on the crystal can sometimes reveal this.

Bad LCD.

Replace and re-test.

Bad LCD cable.

Replace and re-test.

No Memory.

Bad battery.

Replace and re-test. Check R61 per section 2.1. Be aware that most battery failures are caused by a component failure on the board.

Bad reset circuit.

Check reset (U21 pin 9), both during power up, and down. Troubleshoot if necessary.

Distorted audio.

Bad power supply rail.

Check PS rails, and troubleshoot if necessary.

Faulty DASP-24 ASIC.

Replace and retest.

Faulty trace, particularly between the DASP 24 ASIC, and the DAC, or analog switch (U9).

Troubleshoot, and replace if necessary. Faulty op-amp.

Troubleshoot, and replace if necessary.

Faulty analog switch (U9).

Troubleshoot, and replace if necessary.

Faulty power supply bypass capacitor, particularly the cap at the analog switch (U9).

Troubleshoot, and replace if necessary. No MIDI in.

Faulty Opto-isolator (U30).

Replace and retest.

Faulty 8031 (U21).

Replace and retest.

No MIDI out.

Faulty 8031 (U21).

Replace and retest.

Faulty transistor (Q4, Q5).

Replace and retest.

Troubleshooting a complex device, such as the QuadraVerb, can range from the simplicity of looking, seeing, and reseating a loose cable, to examining complex timing relationships of data and control, and replacing the "slightly" bad latch. The following chart is presented in an effort to relieve the beleaguered technician from having to "discover" some of the common fixes we have seen. Please note that we only cover the most likely causes, not all of them.

Customer Complaint Possible Failure Possible Action

A few final notes: The DAC output is an extremely important test point. Familiarity with the appearance of this signal on a scope, will greatly facilitate troubleshooting audio problems. Exercise caution when examining the output of comparator (U8). Accidentally shorting pins 7, and 8 together

Alesis QuadraVerb Service Manual------

Page 19

will instantly result in a dead ASIC. Other than there, and in the power supply, you really can't do any harm with a scope probe, so explore.

The Curtiss VCAs (U5, and possibly U6), are current driven devices, so don't expect to see any signals from these chips on a scope.

Be on the watch for user error. (i.e.,if a user complains that it won't load from a DataDisk, check to be sure that "SYSEX ENABLE" is turned on.)

Remember to install ALL of the latest revisions, before returning the unit. This can help prevent many unhappy returns.

All Trademarks are property of their respective companies.

Alesis QuadraVerb Service Manual------

Page 20

9.0 Schematics

Alesis QuadraVerb Service Manual------ 14

Page 21

Alesis QuadraVerb Service Manual------ 15

Page 22

10.0 Software History

DATE VERSION COMMENTS

1/15/89 1.00 1) First production release

1/23/89 1.01 1) Added test routines for production testing, including RAM, ROM, LEDs, MIDI, and

CLIP tests.

2/22/89 1.02 1) Fixed bug that caused a gated effect to be heard on graphic EQ and delay mode

programs if the previously selected program was a gated program.

2) Fixed bug that caused a volume drop in the mid band EQ if the frequency was 9874Hz, amplitude +14.00 dB, and bandwidth of 2.55 octaves.

3) Default setting for direct signal level changed to 50 from 99.

4) Default setting for reverb level changed to 99 from 50.

5) Fixed bug that caused the bypass level of lezlie programs to be unpredictable. Now, the bypass level will be the same as the lezlie level.

6) All 90 factory programs updated to newer versions.

3/8/89 1.03 1) Changed bypass level of direct signal so that the master effect level would be used to

scale the bypass level if the current program did not have any direct signal in it.

2) Changed default mix settings of the last 10 programs (90-99) so that direct level is 50 (instead of 99), delay is 50 (instead of 40), and reverb is 99 ( instead of 40).

3) All 90 factory programs updated to newer versions.

11/30/89 1.05 1) Software version accommodates new hardware in which VCA after DAC is

removed. This means that the master effects level is controlled by scaling the amplitude of each effect in software, instead of changing the VCA level. If this software is used with older hardware, the VCA will be left full open, so that the operation will be the same as with the newer hardware.

2) When changing programs with bypass on, the dry level will now change with each program to reflect the level of the dry signal in that program.

3) When a program is stored, the display now reads "PROGRAM STORED" instead of "PROGAM STORED".

3/8/90 1.07 1) The 11 band graphic EQ algorithm has been modified to decrease the noise present

when one of the bands between 250Hz and 16KHz was set to a few dB of cut.

2) The duty cycle of the EQ cursor flashing has been changed to improve its visibility.

8/10/90 2.00 1) Quadraverb Plus first release. Too many features to describe.

Alesis QuadraVerb Service Manual------ 16

Page 23

9/5/90 2.01 1) Slight changes to factory programs.

11/14/90 2.02 1) If a sampling program was selected when previously a panning program was

selected, audio triggering and MIDI transposing of the sample would not work properly. This is now fixed.

2) When in Sample configuration, the EQ and BYPASS buttons could not be used to enter a new program number while holding the PROG button. This is now fixed.

3) When selecting a program that was set to the Sample configuration while audio was present would occasionally result in noise at the audio output until a sample was recorded. This is now fixed.

3/10/92 2.03 1) If a MIDI controller was routed to modulate the speed of the chorus, an awful sound

would occur when the controller was moved. This is now fixed.

Alesis QuadraVerb Service Manual------ 17

Page 24

11.0 Quadraverb Plus MIDI Implementation/System Exclusive

SYSTEM EXCLUSIVE FORMAT

The QuadraVerb MIDI System Exclusive message format is as follows:

F0 System exclusive status 00 00 0E Alesis manufacturer id# 02 Quadraverb id# cc Opcode dd Data : : : : F7 End-Of-Exclusive

OPCODES:

01 - MIDI Editting

F0 00 00 0E 02 01<function#><page#>< value1>< value2>< value3>F7

<function#> = 1=reverb, 2=delay, 3=pitch, 4=eq, 7=config, 8=mix, 9=mod, 10=name

<page#> = 0..n where n is the maximum page # for the selected function <value1-3> = new parameter value in the following format:

Data: B7 B6 B5 B4 B3 B2 B1 B0 (MSB) A7 A6 A5 A4 A3 A2 A1 A0 (LSB)

Sent: 0 A7 A6 A5 A4 A3 A2 A1 <value1> 0 A0 B7 B6 B5 B4 B3 B2 <value2> 0 B1 B0 0 0 0 0 0 <value3>

All parameters to be edited must be sent in this format (12 MIDI bytes), regardless of the number of bits

required to transmit the value of the parameter. When the QuadraVerb receives this message, it will edit the specified parameter to the new value and display it. If the function and page selected does not exist in the current configuration, the command will be ignored. If the value received is out of range for the parameter selected, the range will be limited to a legal value. The function and page numbers for each parameter are shown in the next section.

Alesis QuadraVerb Service Manual------ 18

Page 25

02 - MIDI Data Dump F0 00 00 0E 02 02 <program#> <data> F7

<program#> = 0..99 selects individual programs = 100 selects the edit buffer = > 100 selects all 100 programs

<data> is in a packed format in order to optimize data transfer. Eight MIDI bytes are used to transmit each block of 7 QuadraVerb data bytes. If the 7 data bytes are looked at as one 56-bit word, the format for transmission is eight 7-bit words beginning with the most significant bit of the first byte, as follows:

SEVEN QUADRAVERB BYTES:

0: A7 A6 A5 A4 A3 A2 A1 A0

1: B7 B6 B5 B4 B3 B2 B1 B0

2: C7 C6 C5 C4 C3 C2 C1 C0

3: D7 D6 D5 D4 D3 D2 D1 D0

4: E7 E6 E5 E4 E3 E2 E1 E0

5: F7 F6 F5 F4 F3 F2 F1 F0

6: G7 G6 G5 G4 G3 G2 G1 G0

TRANSMITTED AS:

0: 0 A7 A6 A5 A4 A3 A2 A1

1: 0 A0 B7 B6 B5 B4 B3 B2

2: 0 B1 B0 C7 C6 C5 C4 C3

3: 0 C2 C1 C0 D7 D6 D5 D4

4: 0 D3 D2 D1 D0 E7 E6 E5

5: 0 E4 E3 E2 E1 E0 F7 F6

6: 0 F5 F4 F3 F2 F1 F0 G7

7: 0 G6 G5 G4 G3 G2 G1 G0

There are 147 bytes sent for a single data dump, which corresponds to 128 bytes of program data. There

are 14,629 bytes sent for a 100 program dump, which corresponds to 12,800 bytes of program data. The location of each parameter within a program is shown in the next section.

When the QuadraVerb receives a data dump message, the display reads:

LOADING MIDI DATA ...

Should the Quadraverb's MIDI input buffer overflow, the display will read:

Alesis QuadraVerb Service Manual------ 19

Page 26

MIDI INPUT BUFFER OVERFLOW

This message will remain on the display until any button is pressed.

03 - MIDI Dump Request

F0 00 00 0E 02 03 <program#> F7

<program#> = 0..99 selects individual programs = 100 selects the edit buffer = > 100 selects all 100 programs

When this message is received, a MIDI data dump will be initiated, and the display will read:

MIDI DATA DUMP IN PROGRESS

Upon completion of the dump, the display will return to its previously displayed page.

INDIVIDUAL PARAMETER LOCATION FUNCTION AND PAGE VALUES

The following lists give the parameter locations and ranges for each of the effects in each of the configurations. The parameter associated with a particular function and page may be dependent on both the current configuration, and the current mode of the effect (e.g., chorus, phase, etc.). In conditions where a page relates to different parameters depending on the mode of the effect, the parameters are listed in tables under each mode. All parameters are offset binary values. This means that a signed parameter with a range of -99 to +99 in the display is actually stored as 0 for -99, 99 for 0, and 198 for +99.

REVERB (FUNCTION 1)

CONFIGURATION 0, 5, & 6: page 0 (type) 0 (PLATE 1) 1 (ROOM 1) 2 (CHAMBER 1) 3 (HALL 1) 4 (REVERSE 1) 1 0-3 (INPUT 1) 0-3 (INPUT 1) 0-3 (INPUT 1) 0-3 (INPUT 1) 0-3 (INPUT 1) 2 0-1 (INPUT 2) 0-1 (INPUT 2) 0-1 (INPUT 2) 0-1 (INPUT 2) 0-1 (INPUT 2) 3 0-198 (IN MIX) 0-198 (IN MIX) 0-198 (IN MIX) 0-198 (IN MIX) 0-198 (IN MIX) 4 1-140 (PREDLY) 1-140 (PREDLY) 1-140 (PREDLY) 1-140 (PREDLY) 1-140 (PREDLY) 5 1-198 (PRE MIX) 1-198 (PRE MIX) 1-198 (PRE MIX) 1-198 (PRE MIX) 1-198 (PRE MIX) 6 0-99 (DECAY) 0-99 (DECAY) 0-99 (DECAY) 0-99 (DECAY) 0-99 (REV TIME) 7 0-8 (DIFFUSION) 0-8 (DIFFUSION) 0-8 (DIFFUSION) 0-8 (DIFFUSION) 0-8 (DIFFUSION) 8 0-8 (DENSITY) 0-8 (DENSITY) 0-8 (DENSITY) 0-60 (LOW DEC) 0-8 (DENSITY)

Alesis QuadraVerb Service Manual------ 20

Page 27

9 0-60 (LOW DEC) 0-60 (LOW DEC) 0-60 (LOW DEC) 0-60 (HIGH DEC) 0-60 (LOW DEC) 10 0-60 (HIGH DEC) 0-60 (HIGH DEC) 0-60 (HIGH DEC) 0-1 (GATE ON) 0-60 (HIGH DEC) 11 0-1 (GATE ON) 0-1 (GATE ON) 0-1 (GATE ON) 0-99 (GATE HLD) 12 0-99 (GATE HLD) 0-99 (GATE HLD) 0-99 (GATE HLD) 0-99 (GATE REL) 13 0-99 (GATE REL) 0-99 (GATE REL) 0-99 (GATE REL) 0-99 (GATE LEV) 14 0-99 (GATE LEV) 0-99 (GATE LEV) 0-99 (GATE LEV)

CONFIGURATION 1: page 0 (type) 0 (PLATE 1) 1 (ROOM 1) 2 (CHAMBER 1) 3 (HALL 1) 4 (REVERSE 1) 1 0-2 (INPUT 1) 0-2 (INPUT 1) 0-2 (INPUT 1) 0-2 (INPUT 1) 0-2 (INPUT 1) 2-14 same as configuration 0

CONFIGURATION 2, 3 & 7: Not used

CONFIGURATION 4: page 0 (type) 0 (PLATE 2) 1 (ROOM 2) 2 (CHAMBER 2) 3 (HALL 2) 4 (REVERSE 2) 1 0-1 (INPUT) 0-1 (INPUT) 0-1 (INPUT) 0-1 (INPUT) 0-1 (INPUT) 2 1-140 (PREDLY) 1-140 (PREDLY) 1-140 (PREDLY) 1-140 (PREDLY) 1-140 (PREDLY) 3 1-198 (PRE MIX) 1-198 (PRE MIX) 1-198 (PRE MIX) 1-198 (PRE MIX) 1-198 (PRE MIX) 4 0-99 (DECAY) 0-99 (DECAY) 0-99 (DECAY) 0-99 (DECAY) 0-99 (REV TIME) 5 0-8 (DIFFUSION) 0-8 (DIFFUSION) 0-8 (DIFFUSION) 0-8 (DIFFUSION) 0-8 (DIFFUSION) 6 0-8 (DENSITY) 0-8 (DENSITY) 0-8 (DENSITY) 0-60 (LOW DEC) 0-8 (DENSITY) 7 0-60 (LOW DEC) 0-60 (LOW DEC) 0-60 (LOW DEC) 0-60 (HIGH DEC) 0-60 (LOW DEC) 8 0-60 (HIGH DEC) 0-60 (HIGH DEC) 0-60 (HIGH DEC) 0-1 (GATE ON) 0-60 (HIGH DEC) 9 0-1 (GATE ON) 0-1 (GATE ON) 0-1 (GATE ON) 0-99 (GATE HLD) 10 0-99 (GATE HLD) 0-99 (GATE HLD) 0-99 (GATE HLD) 0-99 (GATE REL) 11 0-99 (GATE REL) 0-99 (GATE REL) 0-99 (GATE REL) 0-99 (GATE LEV) 12 0-99 (GATE LEV) 0-99 (GATE LEV) 0-99 (GATE LEV)

DELAY (FUNCTION 2)

CONFIGURATION 0: page 0 (type) 0 (MONO) 1 (STEREO) 2 (PING-PONG)

1 0-1 (INPUT 1) 0-1 (INPUT 1) 0-1 (INPUT 1) 2 0-198 (IN MIX) 0-198 (IN MIX) 0-198 (IN MIX) 3 1-800 (DELAY) 1-400 (L DELAY) 1-400 (DELAY) 4 0-99 (FEEDB) 0-99 (L FEEDB) 0-99 (FEEDB) 5 1-400 (R DELAY) 6 0-99 (R FEEDB)

CONFIGURATION 1, 5: page

Alesis QuadraVerb Service Manual------ 21

Page 28

0 (type) 0 (MONO) 1 (STEREO) 2 (PING-PONG) 1 0-198 (IN MIX) 0-198 (IN MIX) 0-198 (IN MIX) 2 1-800 (DELAY) 1-400 (L DELAY) 1-400 (DELAY) 3 0-99 (FEEDB) 0-99 (L FEEDB) 0-99 (FEEDB) 4 1-400 (R DELAY) 5 0-99 (R FEEDB)

CONFIGURATION 2: page 0 (type) 0 (MONO) 1 (STEREO) 2 (PING-PONG) 1 0-1 (INPUT) 0-1 (INPUT) 0-1 (INPUT) 2 1-1500 (DELAY) 1-750 (L DELAY) 1-750 (DELAY) 3 0-99 (FEEDB) 0-99 (L FEEDB) 0-99 (FEEDB) 4 1-750 (R DELAY) 5 0-99 (R FEEDB)

CONFIGURATION 3: page 0 (type) 0 (MONO) 1 (STEREO) 2 (PING-PONG) 3 (MULTI-TAP) 1 0-1 (INPUT) 0-1 (INPUT) 0-1 (INPUT) 0-1 (INPUT) 2 0-198 (IN MIX) 0-198 (IN MIX) 0-198 (IN MIX) 0-198 (IN MIX) 3 1-1500 (DELAY) 1-750 (L DELAY) 1-750 (DELAY) 0-7 (TAP NUMBER) 4 0-99 (FEEDB) 0-99 (L FEEDB) 0-99 (FEEDB) 1-1493 (TAP DELAY) 5 1-750 (R DELAY) 0-99 (TAP VOLUME) 6 0-99 (R FEEDB) 0-198 (TAP PAN) 7 0-99 (TAP FB) 8 0-99 (MASTER FB)

CONFIGURATION 4: Not used

CONFIGURATION 6: page

Alesis QuadraVerb Service Manual------ 22

Page 29

0 (type) 0 (MONO) 1 (STEREO) 2 (PING-PONG) 1 0-198 (IN MIX) 0-198 (IN MIX) 0-198 (IN MIX) 2 1-720 (DELAY) 1-320 (L DELAY) 1-320 (DELAY) 3 0-99 (FEEDB) 0-99 (L FEEDB) 0-99 (FEEDB) 4 1-320 (R DELAY) 5 0-99 (R FEEDB)

CONFIGURATION 7: page 0 0-2 (SAMPLE PLAYBACK) 1 0-150 (SAMPLE START) 2 0-155 (SAMPLE LENGTH) 3 0-1 (AUDIO TRIG) 4 0-2 (MIDI TRIG) 5 0-127 (MIDI LOW LIMIT) 6 0-127 (MIDI BASE NOTE) 7 0-127 (MIDI HI LIMIT)

PITCH (FUNCTION 3)

CONFIGURATION 0 & 3: page 0 (type) 0 (M CHORUS) 1 (S CHORUS) 2 (M FLANGE) 3 (S FLANGE) 4 (DETUNE) 5 (PHASER) 1 0-1 (INPUT) 0-1 (INPUT) 0-1 (INPUT) 0-1 (INPUT) 0-1 (INPUT) 0-1 (INPUT) 2 0-1 (WAVE) 0-1 (WAVE) 0-99 (SPEED) 0-99 (SPEED) 0-198 (TUNE) 0-99 (SPEED) 3 0-99 (SPEED) 0-99 (SPEED) 0-99 (DEPTH) 0-99 (DEPTH) 0-99 (DEPTH) 4 0-99 (DEPTH) 0-99 (DEPTH) 0-99 (FBACK) 0-99 (FBACK) 5 0-99 (FBACK) 0-99 (FBACK) 0-1 (TRIGGER) 0-1 (TRIGGER)

CONFIGURATION 1: page 0 0-99 (SEPARATION) 1 0-1 (MOTOR) 2 0-1 (SPEED)

CONFIGURATION 2 & 7: Not used

CONFIGURATION 4: page 0 (type) 0 (CHORUS OFF) 1 (CHORUS ON) 1 0-1 (WAVE) 2 0-99 (SPEED) 3 0-99 (DEPTH)

CONFIGURATION 5:

Alesis QuadraVerb Service Manual------ 23

Page 30

page 0 1-300 (RING MOD SPECTRUM) 1 0-198 (RING MOD OUT MIX) 2 0-198 (RING MOD DEL/REV MIX)

CONFIGURATION 6: page 0 0-1 (RESONATOR GATE MODE) 1 0-99 (RESONATOR DECAY) 2 0-60 (RESONATOR 1 TUNE) 3 0-60 (RESONATOR 2 TUNE) 4 0-60 (RESONATOR 3 TUNE) 5 0-60 (RESONATOR 4 TUNE) 6 0-60 (RESONATOR 5 TUNE)

EQ (FUNCTION 4)

CONFIGURATION 0 & 4: page 0 20-999 (LOW FREQUENCY) 1 0-560 (LOW BOOST/CUT) 2 200-9999 (MID FREQUENCY) 3 20-255 (MID BANDWIDTH) 4 0-560 (MID BOOST/CUT) 5 2000-18000 (HIGH FREQUENCY) 6 0-560 (HIGH BOOST/CUT)

CONFIGURATION 1: page 0 0-26 (HIGH ROTOR LEVEL)

CONFIGURATION 2: page 0 0-28 (16Hz) 1 0-28 (32Hz) 2 0-28 (62Hz) 3 0-28 (126Hz) 4 0-28 (250Hz) 5 0-28 (500Hz) 6 0-28 (1KHz) 7 0-28 (2KHz) 8 0-28 (4KHz) 9 0-28 (8KHz) 10 0-28 (16KHz) CONFIGURATION 3: page

Alesis QuadraVerb Service Manual------ 24

Page 31

0 20-999 (LOW FREQUENCY) 1 0-560 (LOW BOOST/CUT) 2 20-500 (LOW MID FREQUENCY) 3 20-255 (LOW MID BANDWIDTH) 4 0-560 (LOW MID BOOST/CUT) 5 200-9999 (MID FREQUENCY) 6 20-255 (MID BANDWIDTH) 7 0-560 (MID BOOST/CUT) 8 2000-18000 (HIGH MID FREQUENCY) 9 20-255 (HIGH MID BANDWIDTH) 10 0-560 (HIGH MID BOOST/CUT) 11 2000-18000 (HIGH FREQUENCY) 12 0-560 (HIGH BOOST/CUT)

CONFIGURATION 5, 6 & 7: Not used

CONFIGURATION (FUNCTION 7)

page 0 0-4 (CONFIGURATION) 0: EQ>PCH>DL>REVERB 1: LESLIE>DL>REVERB 2: GRAPHIC EQ>DELAY 3: 5BAND EQ>PCH>DLY 4: 3 BAND EQ>REVERB 5: RING>DL>REVERB 6: RESONATOR>DL>REVERB 7: SAMPLING

MIX (FUNCTION 8)

CONFIGURATION 0: page 0 (type) 0 (PRE-EQ) 1 (POST-EQ) 1 0-99 (DIRECT) 0-99 (MAST FX) 2 0-99 (MAST FX) 0-99 (EQ) 3 0-99 (PITCH) 0-99 (PITCH) 4 0-99 (DELAY) 0-99 (DELAY) 5 0-99 (REVERB) 0-99 (REVERB)

CONFIGURATION 1: page

Alesis QuadraVerb Service Manual------ 25

Page 32

0 0-99 (MAST FX) 1 0-99 (LESLIE) 2 0-99 (DELAY) 3 0-99 (REVERB)

CONFIGURATION 2: page 0 0-99 (MAST FX) 1 0-99 (EQ) 2 0-99 (DELAY) CONFIGURATION 3:

page 0 (type) 0 (PRE-EQ) 1 (POST-EQ) 1 0-99 (DIRECT) 0-99 (MAST FX) 2 0-99 (MAST FX) 0-99 (EQ) 3 0-99 (PITCH) 0-99 (PITCH) 4 0-99 (DELAY) 0-99 (DELAY)

CONFIGURATION 4: page 0 (type) 0 (PRE-EQ) 1 (POST-EQ) 1 0-99 (DIRECT) 0-99 (MAST FX) 2 0-99 (MAST FX) 0-99 (EQ) 5 0-99 (REVERB) 0-99 (REVERB)

CONFIGURATION 5: page 0 0-99 (MAST FX) 1 0-99 (DIRECT) 2 0-99 (RING MOD) 3 0-99 (DELAY) 4 0-99 (REVERB)

CONFIGURATION 6: page 0 0-99 (MAST FX) 1 0-99 (DIRECT) 2 0-99 (RESONATOR) 3 0-99 (DELAY) 4 0-99 (REVERB)

CONFIGURATION 7: page 0 0-99 (DIRECT) 1 0-99 (SAMPLE)

Alesis QuadraVerb Service Manual------ 26

Page 33

MOD (FUNCTION 9)

CONFIGURATION 0-6: page 0 0-126 (MOD 1 SOURCE) 1 0-? (MOD 1 TARGET) 2 0-198 (MOD 1 AMPLITUDE) 3 0-126 (MOD 2 SOURCE) 4 0-? (MOD 2 TARGET) 5 0-198 (MOD 2 AMPLITUDE) 6 0-126 (MOD 3 SOURCE) 7 0-? (MOD 3 TARGET) 8 0-198 (MOD 3 AMPLITUDE) 9 0-126 (MOD 4 SOURCE) 10 0-? (MOD 4 TARGET) 11 0-198 (MOD 4 AMPLITUDE) 12 0-126 (MOD 5 SOURCE) 13 0-? (MOD 5 TARGET) 14 0-198 (MOD 5 AMPLITUDE) 15 0-126 (MOD 6 SOURCE) 16 0-? (MOD 6 TARGET) 17 0-198 (MOD 6 AMPLITUDE) 18 0-126 (MOD 7 SOURCE) 19 0-? (MOD 7 TARGET) 20 0-198 (MOD 7 AMPLITUDE) 21 0-126 (MOD 8 SOURCE) 22 0-? (MOD 8 TARGET) 23 0-198 (MOD 8 AMPLITUDE)

CONFIGURATION 7: Not used

Modulation target values are dependent on the current configuration and mode of a program. The most significant nibble determines the function being modulated as follows:

0XH: REVERB MOD 1XH: DELAY MOD 2XH: PITCH MOD 3XH: EQ MOD 4XH: MIX MOD 5XH: MULTI-TAP MOD (Configuration 3 only) 6XH: " " " " " " " " "

The possible modulation targets within each of the above is as follows:

Alesis QuadraVerb Service Manual------ 27

Page 34

REVERB CONFIGURATION 0,1,4,5,6 (nothing in 2, 3, & 7):

Target PLATE ROOM CHAMBER HALL REVERSE 00H IN MIX IN MIX IN MIX IN MIX IN MIX 01H PREDLY PREDLY PREDLY PREDLY PREDLY 02H PRE MIX PRE MIX PRE MIX PRE MIX PRE MIX 03H DECAY DECAY DECAY 0DECAY REV TIME 04H DIFFUSION DIFFUSION DIFFUSION DIFFUSION DIFFUSION 05H DENSITY DENSITY DENSITY LOW DEC DENSITY 06H LOW DEC LOW DEC LOW DEC HIGH DEC LOW DEC 07H HIGH DEC HIGH DEC HIGH DEC HIGH DEC

DELAY CONFIGURATION 0,1 (nothing in 4 & 7):

Target MONO STEREO PING-PONG 10H IN MIX IN MIX IN MIX

11H DELAY L DELAY DELAY 12H FEEDB L FEEDB FEEDB

13H R DELAY 14H R FEEDB

CONFIGURATION 3:

Target MONO STEREO PING-PONG MULTI-TAP 10H IN MIX IN MIX IN MIX IN MIX

11H DELAY L DELAY DELAY TAP 1 DELAY 12H FEEDB L FEEDB FEEDB TAP 2 DELAY

13H R DELAY TAP 3 DELAY 14H R FEEDB TAP 4 DELAY 15H TAP 5 DELAY 16H TAP 6 DELAY 17H TAP 7 DELAY 18H TAP 8 DELAY 50H TAP 1 VOLUME 51H TAP 2 VOLUME 52H TAP 3 VOLUME 53H TAP 4 VOLUME 54H TAP 5 VOLUME 55H TAP 6 VOLUME 56H TAP 7 VOLUME 57H TAP 8 VOLUME 58H TAP 1 PANNING 59H TAP 2 PANNING 5AH TAP 3 PANNING 5BH TAP 4 PANNING 5CH TAP 5 PANNING 5DH TAP 6 PANNING

Alesis QuadraVerb Service Manual------ 28

Page 35

5EH TAP 7 PANNING 5FH TAP 8 PANNING 60H TAP 1 FEEDBACK 61H TAP 2 FEEDBACK 62H TAP 3 FEEDBACK 63H TAP 4 FEEDBACK 64H TAP 5 FEEDBACK 65H TAP 6 FEEDBACK 66H TAP 7 FEEDBACK 67H TAP 8 FEEDBACK 68H MASTER FEEDBACK

CONFIGURATION 2,5,6:

Target MONO STEREO PING-PONG 10H DELAY L DELAY DELAY

11H FEEDB L FEEDB FEEDB 12H R DELAY 13H R FEEDB

PITCH CONFIGURATION 0 & 3 (nothing in 2 & 7):

Target M CHORUS S CHORUS M FLANGE S FLANGE DETUNE PHASER 20H SPEED SPEED SPEED SPEED DETUNE SPEED 21H DEPTH DEPTH DEPTH DEPTH DEPTH 22H FBACK FBACK FBACK FBACK

CONFIGURATION 1: Target 20H SEPARATION 21H MOTOR 22H SPEED

CONFIGURATION 4: Target 20H SPEED 21H DEPTH

CONFIGURATION 5: Target 20H SPECTRUM SHIFT 21H RING OUTPUT MIX 22H DEL/REV IN MIX CONFIGURATION 6: Target

Alesis QuadraVerb Service Manual------ 29

Page 36

20H RESONATOR DECAY

EQ CONFIGURATION 0 & 4 (nothing in 5, 6, & 7):

Target 30H LOW FREQUENCY 31H LOW BOOST/CUT 32H MID FREQUENCY 33H MID BANDWIDTH 34H MID BOOST/CUT 35H HIGH FREQUENCY 36H HIGH BOOST/CUT

CONFIGURATION 1: Target 30H HIGH ROTOR LEVEL

CONFIGURATION 2: Target 30H 16Hz 31H 32Hz 32H 62Hz 33H 126Hz 34H 250Hz 35H 500Hz 36H 1KHz 37H 2KHz 38H 4KHz 39H 8KHz 3AH 16KHz

CONFIGURATION 3: Target 30H LOW FREQUENCY 31H LOW BOOST/CUT 32H LOW MID FREQUENCY 33H LOW MID BANDWIDTH 34H LOW MID BOOST/CUT 35H MID FREQUENCY 36H MID BANDWIDTH 37H MID BOOST/CUT 38H HIGH MID FREQUENCY 39H HIGH MID BANDWIDTH 3AH HIGH MID BOOST/CUT 3BH HIGH FREQUENCY 3CH HIGH BOOST/CUT

Alesis QuadraVerb Service Manual------ 30

Page 37

MIX CONFIGURATION 0:

Target PRE-EQ POST-EQ 40H DIRECT MAST FX 41H MAST FX EQ 42H PITCH PITCH 43H DELAY DELAY 44H REVERB REVERB

CONFIGURATION 1: Target 40H MAST FX 41H LESLIE 42H DELAY 43H REVERB

CONFIGURATION 2: Target 40H MAST FX 41H EQ 42H DELAY

CONFIGURATION 3: Target 40H DIRECT 41H MAST FX 42H PITCH 43H DELAY

CONFIGURATION 4: Target 40H DIRECT 41H MAST FX 42H REVERB

CONFIGURATION 5: Target 40H DIRECT 41H MAST FX 42H RING MOD 43H DELAY

44H REVERB

Alesis QuadraVerb Service Manual------ 31

Page 38

CONFIGURATION 6: Target 40H DIRECT 41H MAST FX 42H RESONATOR 43H DELAY

44H REVERB

NAME (FUNCTION 10)

CONFIGURATION 0-4: page 0 32-127 (1st DIGIT NAME) 1 32-127 (2nd DIGIT NAME) 2 32-127 (3rd DIGIT NAME) 3 32-127 (4th DIGIT NAME) 4 32-127 (5th DIGIT NAME) 5 32-127 (6th DIGIT NAME) 6 32-127 (7th DIGIT NAME) 7 32-127 (8th DIGIT NAME) 8 32-127 (9th DIGIT NAME) 9 32-127 (10th DIGIT NAME) 10 32-127 (11th DIGIT NAME) 11 32-127 (12th DIGIT NAME) 12 32-127 (13th DIGIT NAME) 13 32-127 (14th DIGIT NAME)

Alesis QuadraVerb Service Manual------ 32

Page 39

PARAMETER ADDRESSES WITHIN PROGRAMS

The following addresses are relative to the first address of a program. These addresses assume that the data has been unpacked into byte values. Blank locations should be left 0.

00 LOW EQ FREQ MSB 01 LOW EQ FREQ LSB / 16Hz 02 LOW EQ AMP MSB / 32Hz 03 LOW EQ AMP LSB / 62Hz 04 MID EQ FREQ MSB / 126Hz 05 MID EQ FREQ LSB / 250Hz 06 MID EQ BANDWIDTH / 500Hz 07 MID EQ AMP MSB / 1KHz 08 MID EQ AMP LSB / 2KHz 09 HIGH EQ FREQ MSB / 4KHz 0A HIGH EQ FREQ LSB / 8KHz 0B HIGH EQ AMP MSB / 16KHz 0C HIGH EQ AMP LSB 0D LESLIE HIGH ROTOR LEVEL / TAP 1 DELAY MSB 0E LOW MID EQ FREQ MSB 0F LOW MID EQ FREQ LSB 10 LOW MID EQ BANDWIDTH 11 LOW MID EQ AMP MSB 12 LOW MID EQ AMP LSB 13 HIGH MID EQ FREQ MSB 14 HIGH MID EQ FREQ LSB 15 HIGH MID EQ BANDWIDTH 16 HIGH MID EQ AMP MSB 17 HIGH MID EQ AMP LSB 18 SAMPLE START / TAP 1 DELAY LSB

19 SAMPLE LENGTH / TAP 1 VOLUME 1A PITCH MODE 1B PITCH INPUT 1C LFO WAVEFORM 1D LFO SPEED 1E LFO DEPTH / RESONATOR DECAY 1F SAMPLE PLAYBACK MODE / TAP 1 PAN 20 PITCH FEEDBACK 21 DETUNE AMOUNT / SAMPLE PITCH 22 LESLIE SEPARATION / TAP 1 FEEDBACK 23 LESLIE MOTOR / SAMPLE REC AUDIO TRIG /

TAP 2 DELAY MSB 24 LESLIE SPEED / SAMPLE MIDI TRIG /

TAP 2 DELAY LSB 25 TRIGGER FLANGE / RES MIDI GATE 26 SAMPLE MIDI BASE NOTE / TAP 2 VOLUME 27 DELAY MODE 28 DELAY INPUT 29 DELAY INPUT MIX 2A DELAY MSB / LEFT DELAY MSB / TAP 2 PAN 2B DELAY LSB / LEFT DELAY LSB /TAP 2 FEEDBACK 2C FEEDBACK / LEFT FEEDBACK / TAP 3 DELAY MSB 2D RIGHT DELAY MSB / TAP 3 DELAY LSB 2E RIGHT DELAY LSB / TAP 3 VOLUME 2F RIGHT FEEDBACK / TAP 3 PAN 30 SAMPLE LOW MIDI NOTE / TAP 3 FEEDBACK

31 SAMPLE HIGH MIDI NOTE / TAP 4 DELAY MSB 32 REVERB MODE / TAP 4 DELAY LSB 33 TAP 4 VOLUME 34 REVERB INPUT 1 / TAP 4 PAN 35 REVERB INPUT 2 / TAP 4 FEEDBACK 36 REVERB INPUT MIX / TAP 5 DELAY MSB 37 REVERB PREDELAY / TAP 5 DELAY LSB 38 REVERB PREDELAY MIX / TAP 5 VOLUME 39 REVERB DECAY / TAP 5 PAN 3A REVERB DIFFUSION / TAP 5 FEEDBACK

3B REVERB LOW DECAY / TAP 6 DELAY MSB 3C REVERB HIGH DECAY / TAP 6 DELAY LSB 3D REVERB DENSITY / TAP 6 VOLUME 3E REVERB GATE / TAP 6 PAN

3F REVERB GATE HOLD / TAP 6 FEEDBACK 40 REVERB GATE RELEASE / TAP 7 DELAY MSB

41 REVERB GATED LEVEL / TAP 7 DELAY LSB 42 RING MOD SHIFT MSB / TAP 7 VOLUME

43 RING MOD SHIFT LSB / TAP 7 PAN 44 CONFIGURATION 45 PRE (00), POST (01), POST PANNING (10), POST TREMOLO (11) 46 DIRECT LEVEL / EQ LEVEL 47 MASTER EFFECTS LEVEL 48 PITCH LEVEL / LESLIE LEVEL / RING MOD LEV 49 DELAY LEVEL 4A REVERB LEVEL 4B RESONATOR PITCH 1 / TAP 8 DELAY MSB

4C RESONATOR PITCH 2 / TAP 8 DELAY LSB 4D RESONATOR PITCH 3 / TAP 8 VOLUME 4E RESONATOR PITCH 4 / TAP 8 PAN 4F RESONATOR PITCH 5 / TAP 8 FEEDBACK

50 MOD 1 SOURCE 51 MOD 1 TARGET 52 MOD 1 AMPLITUDE 53 MOD 2 SOURCE 54 MOD 2 TARGET 55 MOD 2 AMPLITUDE 56 MOD 3 SOURCE 57 MOD 3 TARGET 58 MOD 3 AMPLITUDE 59 MOD 4 SOURCE 5A MOD 4 TARGET 5B MOD 4 AMPLITUDE 5C MOD 5 SOURCE 5D MOD 5 TARGET 5E MOD 5 AMPLITUDE 5F MOD 6 SOURCE 60 MOD 6 TARGET 61 MOD 6 AMPLITUDE 62 MOD 7 SOURCE 63 MOD 7 TARGET 64 MOD 7 AMPLITUDE 65 MOD 8 SOURCE 66 MOD 8 TARGET 67 MOD 8 AMPLITUDE 68 MULTITAP MASTER FEEDBACK

69 MULTITAP NUMBER 6A 1ST DIGIT NAME 6B 2ND DIGIT NAME 6C 3RD DIGIT NAME 6D 4TH DIGIT NAME 6E 5TH DIGIT NAME 6F 6TH DIGIT NAME 70 7TH DIGIT NAME 71 8TH DIGIT NAME 72 9TH DIGIT NAME 73 10TH DIGIT NAME 74 11TH DIGIT NAME 75 12TH DIGIT NAME 76 13TH DIGIT NAME 77 14TH DIGIT NAME 78 RING MOD OUTPUT MIX

79 RING MOD DEL/REV MIX 7A PAN SPEED 7B PAN DEPTH 7C-7F (blank)

Alesis QuadraVerb Service Manual------ 33

Page 40

12.0 Quadraverb Service Parts List

GROUP

DESCRIPTION

ALPARTNO

QTYPER

POSITION

PCB

MANUFACTURER

NOTES

ASSY

PCB, MAIN ASSY

8-20-0044

MAIN BOARD

ASSY

PCB, KEYPAD ASSY

8-20-0045

KEYPAD (BUTTON BOARD)

CAB

14 PIN DIL 11.5 0.1 CTR

4-18-1214

MAIN-LCD

CAB

12 PIN SIL 3 0.1 CTR

4-19-0312

J3,4

MAIN-KEY

CAB

6 PIN SIL 6 0.1 CTR

4-19-0606

MAIN-LED

CAB

12 PIN SIL 7 0.1 CTR

4-19-0712

MAIN-POT

CAP

0.1 MF CERDISC

1-02-0104

C54,57-64,66-73,75-78

MAIN

CAP

1000 MF ELEC 16V

1-08-0108

C17,18,19,20

MAIN

CAP

470 MF ELEC 25V

1-09-0477

C21,22,23,24

MAIN

CAP

4.7 MF ELEC 50V

1-11-0475

C1-16,25

MAIN

CER

150 PF CERDISC

1-02-0151

C26,27,47,51

MAIN

CER

180 PF CERDISC

1-02-0181

C28-30,35,36,37,42,44

MAIN

CER

20 PF CERDISC

1-02-0200

C32,33,34

MAIN

CER

330 PF CERDISC

1-02-0331

C43

MAIN

CER

43 PF CERDISC

1-02-0430

C79-86 (MAY SUB W/47 PF)

MAIN

FIL

1000 PF FILM

1-20-0102

C38

MAIN

FIL

0.01 MF FILM

1-20-0103

C41,46,50

MAIN

FIL

0.1 MF FILM

1-20-0104

C45,52,53,55,56,65

MAIN

FIL

2200 PF FILM

1-20-0222

C39,40

MAIN

FIL

0.022 MF FILM

1-20-0223

MAIN

FIL

3300 PF FILM

1-20-0332

C48,49

MAIN

HDR

14 PIN DIL HDR 0.1 CTR

4-14-0014

MAIN

HDR

6 PIN SIL HDR 0.1 CTR

4-15-0006

LED PCB

LED

HDR

12 PIN SIL HDR 0.1 CTR

4-15-0012

J1,3,4,TWO ON KEY PCB

MAIN-KEY

LOCK

HDR

12 PIN SIL HDR RA 0.1

4-15-0013

POT PCB

POT RA LOCK

HDR

6 PIN SIL HDR RA 0.1

4-15-1006

MAIN

HDW

6-32x1/4 PP BLK UNC

5-00-0003

CASE

HDW

6-32x1/4 PF BLK UNC

5-00-0004

F/P HDW

BEZEL SCREW

5-00-0012

INC W/BEZEL

HDW

#6 INT STAR WASHER

5-01-0002

HEATSINKS

HDW

0.95 NYLON SPACER

5-01-0007

F/P ASSY

HDW

7/16 STAR WASHER

5-01-0008

HDW

0.050 NYLON WASHER

5-01-0050

3RD STANDOFF ON SINK

HDW

6-32x1/2 STANDOFF

5-02-0003

FP/HEATSINK

HDW

6-32 KEP NUT

5-02-6320

F/P

HDW

ANGLE BRACKET F/P

5-07-0001

F/P HDW

HEAT SINK

9-03-1022

HDW

SOLDER LUG (PCB MNT)

9-03-1036

PCB LUG

HDW

CABLE BRACKET

9-13-1012

HDW

RUBBER STRIP 5 IN

9-23-1006

LCD TOP & BOTTOM

7805 +5 V TO220

2-11-7805

U33

MAIN

NAT ONLY

TO-220

7812 +12 V TO220

2-11-7812

U31

MAIN

NAT ONLY

TO-220

7912 -12 V TO220

2-11-7912

U32

MAIN

NAT ONLY

TO-220

74HC138 DEMUX

2-14-0138

U23

MAIN

NAT/TI

16 PIN DIP 0.3

74HC573 3-STATE LATCH

2-14-0573

U20

MAIN

NAT/TI

20 PIN DIP 0.3

74HC574 OCTAL FF

2-14-0574

U27,28,29

MAIN

NAT/TI

20 PIN DIP 0.3

Alesis QuadraVerb Service Manual------ 34

Page 41

Alesis QuadraVerb Service Manual------ 35

74HC00 QUAD 2-IN NAND

2-14-7400

U26

MAIN

NAT/TI

14 PIN DIP 0.3

74HCU04 HEX INVERTER

2-14-7403

U25

MAIN

NAT/TI

14 PIN DIP 0.3

74HC74 DUAL D FF

2-14-7474

U24

MAIN

NAT/TI

14 PIN DIP 0.3

64Kx4 DRAM

2-16-4464

U12-16

MAIN

TI/SAMSUNG/HYUNDAI/FUJI

18 PIN DIP 0.3

32Kx8 SRAM 58257

2-17-0257

U18

MAIN

SONY

28 PIN DIP 0.6

27C512 EPROM

2-19-0512

U19

MAIN

NAT/TI/INTEL

28 PIN DIP 0.6

80C31 MPU

2-20-8031

U21

MAIN

SIG/INTEL

40 PIN DIP 0.6

TL084 QUAD OP AMP

2-21-0084

U1-4,22

MAIN

14 PIN DIP 0.3

CEM3381 DVCA

2-21-3381

MAIN

CURTISS

8 PIN DIP 0.3

LM311 ANALOG COMP

2-22-0311

MAIN

8 PIN DIP 0.3

LM339 QUAD COMP

2-22-0339

MAIN

14 PIN DIP 0.3

4053 ANALOG SWITCH

2-23-4053

MAIN

ST/HAR/RCA/SIG

16 PIN DIP 0.3

6N138 OPTOISO

2-24-0138

U30

MAIN

8 PIN DIP 0.3

PCM54 DAC

2-25-0054

U10

MAIN

BURR-BROWN

28 PIN DIP 0.6

ZAK 24 ASIC

2-27-0005

U11

MAIN

HARRIS

PLCC-84

JAC

5 PIN DIN JACK

4-00-0001

J9,10 (MIDI)

MAIN

JAC

4 PIN DIN JACK (P4)

4-00-0004

MAIN

JAC

1/4 CLIFF (MONO)

4-02-0001

J7,8,11-14

MAIN

LCD

LCD MODULE

9-44-1111

F/P ASSY

1N4148 SIGNAL DIODE

2-00-4148

D2-9

MAIN

DO-41/0.3 SPC

1N4003 POWER DIODE

2-01-4003

D10-14

MAIN

DO-27/0.5 SPC

1N5231B ZENER

2-02-5231

D15

MAIN

MOT ONLY

DO-41/0.3 SPC

2N4401 NPN TRANS

2-03-4401

Q1-6

MAIN

HARRIS/MOT/NAT

TO-92/0.1 SPC

LED (GRN)

3-00-0001

LED PCB

LED

LED (RED)

3-02-0001

LED PCB (1), KEY PCB (12)

KEY/LED

PIEZO

7-00-0001

KEY PCB

KEY

24 MHz XTAL

7-01-0006

MAIN

20K LPF

7-20-0001

1 MAIN

LITHIUM BATTERY (3.6V)

7-05-0001

MAIN

TADIRAN

MTL

SIDE PANEL

9-03-1003

MTL

COVER PANEL

9-03-1005

MTL

FRONT PANEL

9-03-1018

MTL

REAR PANEL

9-03-1019

PCB

PCB, QV MAIN REV F

9-40-1019

1 REV F

PCB

PCB, QV KEYPAD

9-40-1020

1 REV B

PCB

PCB, QV LED

9-40-1021

1 REV B

PCB

PCB, QV POT

9-40-1022

PLS

STANDARD KNOB

9-11-1001

PLS

SWITCH BOOT

9-11-1013

PLS

LCD BEZEL (REV B)

9-11-1015

PLS

POWER BUTTON

9-11-1016

PLS

LED BUTTON

9-11-1017

PLS

PLAIN BUTTON

9-11-1018

PLS

SWITCH XTENDER

9-11-1019

POT

10KA DUAL

0-09-1001

POT PCB (O/P)

POT

10KB DUAL

0-09-1004

POT PCB (I/P)

POT

RES

1K 1/8W 5%

0-00-0102

R1,2,4,5,43,44,58,60,16

MAIN

RES

10K 1/8W 5%

0-00-0103

R52,53,61,62,66,75

MAIN

RES

100K 1/8W 5%

0-00-0104

R82,83

MAIN

RES

1M 1/8W 5%

0-00-0105

R3,6,57

MAIN

RES

1.1K 1/8W 5%

0-00-0112

R28,29,30,31

MAIN

Page 42

Alesis QuadraVerb Service Manual------ 36

RES

12K 1/8W 5%

0-00-0123

R81

MAIN

RES

1.5K 1/8W 5%

0-00-0152

R78

MAIN

RES

180K 1/8W 5%

0-00-0184

R39

MAIN

RES

2K 1/8W 5%

0-00-0202

R10-13,35,37,72,73,84-90

MAIN

RES

20K 1/8W 5%

0-00-0203

R7,8,24,32-34,45,77,95

MAIN

RES

220 1/8W 5%

0-00-0221

R50,56,63,64,67,68,91-94

MAIN

RES

2.2M 1/8W 5%

0-00-0225

R55

MAIN

RES

3K 1/8W 5%

0-00-0302

R79

MAIN

RES

3.3K 1/8W 5%

0-00-0332

R69,70

MAIN

RES

330K 1/8W 5%

0-00-0334

R27

MAIN

RES

390K 1/8W 5%

0-00-0394

R40

MAIN

RES

470 1/8W 5%

0-00-0471

R9,14,15,17,18,54,65,96

MAIN

RES

4.7K 1/8W 5%

0-00-0472

R21,46,49,59,71,74,76,97

MAIN

RES

51K 1/8W 5%

0-00-0513

R47,48

MAIN

RES

510K 1/8W 5%

0-00-0514

R36,51

MAIN

RES

560 1/8W 5%

0-00-0561

R19,20

MAIN

RES

5.6K 1/8W 5%

0-00-0562

R25

MAIN

RES

6.2K 1/8W 5%

0-00-0622

R80

MAIN

RES

750 1/8W 5%

0-00-0751

R42

MAIN

RES

75K 1/8W 5%

0-00-0753

R23

MAIN

RES

750K 1/8W 5%

0-00-0754

R41

MAIN

RES

8.2K 1/8W 5%

0-00-0822

R26

MAIN

RES

91K 1/8W 5%

0-00-0913

R38

MAIN

RUB

RUBBER KEYPAD

9-23-1005

F/P ASSY

SOC

18 PIN DIP 0.3

4-04-0018

U12-16

MAIN

SOC

28 PIN DIP 0.6

4-06-0028

U10,18,19

MAIN

SOC

40 PIN DIP 0.6

4-06-0040

U21

MAIN

SOC

84 PIN ASIC SOC

4-12-0084

U11

MAIN

PLCC-84

SWT

DPDT SWITCH

6-02-0001

S1 (POWER)

Page 43

Index

+10V, 2, 4 +12V, 1 +5V, 1, 4, 12

-12V, 1

12MHz, 4

24MHz clock, 4, 6

4053, 2, 3, 35

58256, 2

7805, 1, 2, 34 7812, 1, 34 7912, 1, 34

8031, 4, 5, 6, 12, 35 80C31, 1, 4, 12, 35

A15, 5 algorithm, 1, 4, 5, 16 analog switch, 2, 12, 35 analog to digital, 3 anti-aliasing, 2, 3 Arithmetic Logic Unit, 5 ASIC, 4, 5, 12, 13, 35, 36 audio pop, 6

backup, 2, 4 battery, 2, 4, 7, 12, 35 bypass capacitors, 1

C1, 2, 34 C11, 7 C13, 6 C14, 1 C15, 1 C16, 2 C17-C20, 1 C2, 2 C21, 1, 34 C22, 1 C23, 1 C24, 1 C25, 4 C28-30, 4, 34 C3, 1

C31, 1 C32, 4, 34 C35-37, 4 C38, 2, 3, 34 C39, 2, 34 C40, 2 C42, 4, 8 C44, 4, 8 C56, 5 C7, 1 CA, 8, 9 CAS, 6 CHORUS, 1, 17, 20, 23, 29 clip LED, 6 CLK, 6 comparator, 2, 4, 13

D12, 1, 12 D13, 1 D14, 1 D15, 4, 7, 35 D3, 2 D4, 2 D6, 7 D7, 4 DAC, 2, 4, 6, 8, 9, 12, 13, 16, 35 DASP 24, 2, 4, 5, 6, 12 data, 2, 4, 5, 6, 7, 12 DataDisk, 6, 13 DELAY, 16, 18, 21, 22, 23, 25, 26, 27, 28,

29, 31, 32, 33 demux, 5, 34 DETUNE, 23, 29, 33 divide by 2, 4 DRAM, 6, 35

EPROM, 4, 6, 35 EQ, 16, 17, 18, 24, 25, 26, 27, 30, 31, 33

FEEDBACK, 29, 33 FLANGE, 1, 23, 29, 33

I/O, 4, 5 I/P Filter Kit, 8

J2, 7, 34 J6, 1, 35

LC block filter, 3 LCD, 7, 12, 34, 35 LED, 2, 5, 6, 7, 34, 35

Alesis QuadraVerb Service Manual------ 37

LESLIE, 25, 26, 31, 33 Lithium, 2, 35 LSTMSB, 6

MEM PWR, 2 microprocessor, 2 MIDI, 4, 6, 7, 12, 16, 17, 18, 19, 20, 23,

33, 35 MIX, 16, 18, 20, 21, 22, 23, 24, 25, 27,

28, 30, 31, 33 Modulation, 27, 28 Most Significant Bit, 3, 4, 5 MPU, 4, 35

Nyquist, 3

OPCODES, 18 opto isolator, 7 overflow, 2, 6 OVFLO, 6

PANNING, 17, 28, 29, 33 PHASER, 23, 29 PITCH, 18, 23, 25, 26, 27, 29, 31, 33 power supply, 1, 2, 6, 12, 13

Q2, 5 Q3, 4 Q4, 12 Q5, 12 QuadraVerb, 1, 2, 3, 4, 5, 6, 8, 12, 17, 18 Quadraverb, i, ii, 3, 4, 5, 6, 8, 12, 17, 18,

19, 20, 34

R11, 8 R12, 8 R14, 2 R16, 4, 8, 9 R17, 2 R18, 2 R20, 8, 9 R26, 8, 9, 36 R27, 9, 36 R3, 2, 36 R35, 4 R36, 6, 36 R42, 9, 36 R42a, 8, 9 R43, 8, 9 R44, 8, 9 R45, 8, 9

Page 44

R47, 6, 36 R48, 6 R51, 5 R58, 4 R59, 4, 5 R6, 2 R60, 4 R61, 2, 12 R66, 7 R84-90, 4 R9, 2, 36 R95, 4 RA, 8, 9, 34 RAM, 6, 12, 16 RAS, 6 RB, 8, 9 read, 4, 12 regulator, 1, 2, 4 reset, 2, 4, 5, 6, 7, 12 RESONATOR, 24, 25, 26, 30, 32, 33 REVERB, 16, 18, 20, 25, 26, 27, 28, 31,

32, 33 RF, 4 RING MOD, 24, 26, 32, 33 RISC, 5

ROM, 6, 16 RST, 6 RXD, 4

S1, 1, 36 SAMPLE, 2, 3, 4, 6, 17, 23, 27, 33 sample and hold, 2, 3, 6 SAMPLING, 17 SAR, 4, 5 scope sync, 4 self diagnostics, 6 SRAM, 2, 4, 5, 6, 7, 35 standby current, 2 STB, 6 Successive approximation, 3, 4, 5 System Exclusive, 18 System exclusive, 18

trimpot, 6, 8, 9 TXD, 4

U1, 2, 35 U18, 4, 35 U19, 4, 35 U2, 2

U20, 4, 35 U22, 5 U23, 5, 34 U24, 2, 4, 35 U25, 4, 5, 35 U26, 5, 35 U3, 2, 9 U30, 7, 12, 35 U31, 1, 34 U4, 2 U5, 2, 13, 35 U6, 2, 7, 13 U7, 2, 35 U8, 2, 4, 13, 35 U9, 2, 3, 4, 12, 35

VCA, 2, 7, 16 Vcc, 2

writable control store, 5 write, 4, 5, 6 WRN, 5

Z1, 4, 6, 12, 35 Zener, 7, 35

Alesis QuadraVerb Service Manual------ 38

Page 45

Service Manual History

6/28/94 1.00 First release.

Alesis QuadraVerb Service Manual------ 39

Page 46

NOTES

Alesis QuadraVerb Service Manual------ 40