True P2 User Manual

TRUE

systems

P2

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2-CHANNEL PRECISION MICROPHONE PREAMPLIFIER

with M/S decoding, Direct Inputs and Stereo Phase Correlation Display

OPERATION MANUAL

Version 1.1

2

SAFETY and OPERATING PRECAUTIONS

Important Information:

This symbol indicates the presence of dangerous voltage within the product
enclosure that presents the risk of electric shock injury. When this symbol
appears next to an operation discussed in this manual, only qualified

technical personnel should perform that operation.

This symbol indicates important operating or maintenance instructions that
should be read carefully. Failure to observe these instructions could result in
damage to the product or other property.

WARNINGS:

 To reduce the risk of electric shock injury, do not remove the top cover or rear

panel. Uninsulated dangerous voltage exists within the product’s enclosure.
Refer servicing to qualified personnel.

 Do not defeat the earth ground connection in the AC power cable. Tips for eliminating

ground loops are discussed in the “TROUBLESHOOTING” section of this manual.

 Do not operate this unit in the presence of rain, liquids or condensing moisture. Liquid

entering the product enclosure presents the risk of electric shock injury. Do not touch
the AC plug or enclosure with wet hands.

 Do not defeat intended AC power connection polarization.
 Do not use a damaged or excessively worn cord to connect this unit to AC power.

CAUTIONS:

 Severe damage may be caused to your unit if the AC voltage setting is not correct

for the AC power available in your area. The voltage setting is visible on the red

selector switch on the rear panel. See section on “AC Mains Connection” for instructions
on selecting the proper AC voltage setting. If you are unsure about this, contact your
dealer or TRUE Systems. Product failure caused by improper voltage setting will not
be covered under warranty.

 Do not operate this unit in the presence of rain, liquids or condensing moisture. Liquid

entering the product enclosure is likely to cause performance degradation or failure.
Failures due to moisture entering the enclosure will not be covered under warranty.

 Should liquid spill on the unit, immediately disconnect it from the AC power source and

return it to your dealer or TRUE Systems for servicing.

 This product is designed to operate in an ambient temperature environment not to

exceed 50C (122F). Please ensure that this unit is mounted in such a way that vents
are not blocked and ambient temperature does not exceed 50C.

3

CERTIFICATIONS
FCC Notice

This product complies with the limits for a Class A digital device, pursuant to Part 15 of
the FCC rules. These limits are designed to provide reasonable protection against
harmful interference when operated in a commercial environment. This equipment
generates, uses, and can radiate radio frequency energy and, if not installed and used
in accordance with instructions in this manual, may cause harmful interference to radio
communications. Operation of this equipment in a residential area may cause harmful
interference to radio communications – which can be determined by turning the product
off and on. If this product does cause harmful interference, the user should try to correct
the interference by one or more of the following measures:

1. Re-orient or relocate the receiving antenna.

2. Increase the separation between this product and the receiver.

3. Connect this product to an outlet on a different circuit from that to which the receiver
is connected.

4. Consult the dealer or an experienced radio/TV technician for help.

NOTE: Modifications to the product not expressly approved by Sunrise Engineering and
Design Inc. could void the user’s authority to operate the equipment.

Declaration of Conformity – CE

Sunrise Engineering and Design Inc. hereby declares the TRUE Systems P2
2-channel microphone preamplifier to be in material conformity with the following
directives and related standards:

 73/23/EEC – Low Voltage Directive
 89/336/EEC – EMC Directive
 EN60065:1998
 EN55103-1: 1997
 EN55103-2: 1997

Technical files are maintained at corporate headquarters of Sunrise Engineering and
Design Inc., 1634 S. Research Loop, Suite 110, Tucson, Arizona 85710, USA.

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Owner’s Record

We recommend that you record the following information for reference in the event that
you need to contact TRUE Systems for technical support or repairs. Please return
your completed Warranty Card today.

Serial No._____________________ Purchase Date ______________________
Dealer _____________________________________________________________
Address ____________________________________________________________
Phone _______________________

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OPERATION MANUAL

CONTENTS

SAFETY and OPERATING PRECAUTIONS..............…… … … ....… ....2

CERTIFICATIONS… ..… … … … … … … … … … … … … … … … … … … … … … ...3
Owner’s Record… … … … … … … … … … … … … … … … … … … … … … … … … .3
Table of Contents… … … … … … … … … … … … … … … … … … … … … … … … .4

INTRODUCTION… .......................................................................… … … … ..5

PRODUCT OVERVIEW…..................................................................… … ..5

UP-AND-RUNNING IN A HURRY................................................… … … .6

INSTALLATION..........................................................................… … … … … 7

Unpacking and Inspection… … … … … … … … … … … … … … … … … … ..7
Mounting… … … … … … … … … … … … … … … … … … … … … … … … … … ..7
Ventilation… … … … … … … … … … … … … … … … … … … … … … … … … … 7

OPERATION....................................................................................… … … ..8

Connections… … … … … … … … … … … … ..… … … … … … … … … … … … .8

AC Mains Connection… … … … … … … … … … … … … … … … … … .8
Microphone Connection… … … … … … … … … … … … … … … … … .8
Output Cable Connection… … … … … … … … … … … … … … … … ..9

A Word About Cables… … … … … … … … … … … … … … .… … … … … … .9

Front Panel Controls… … … … … … … ..........................… .........… … … .9

Direct Inputs… … … … … … … … … … … … .....................................… ...12

More About M/S Decoding ...................................................… … … .12

Stereo Phase Correlation Display................................… … … .........13

DESIGN APPROACH.................................................................… … ..… 15

SPECIFICATIONS..........................................................................… . … 15

TROUBLESHOOTING..… … ........................................................… … … 16

REGISTRATION and WARRANTY… .… … … ......................… … … … .17

SERVICE and SUPPORT INFORMATION… ...… … … … … … … … … 18

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OPERATION MANUAL

INTRODUCTION

The P2
necessary for the most critical direct tracking and live sound applications. It includes a
unique combination of functions that make it useful as a complete input system for
standalone or PC-based recording systems. And, the P2
that provide the serious musician or recordist with useful tools to get the best sound
more quickly and easily.

We appreciate the confidence you have placed in TRUE Systems by purchasing this
product. Please feel free to contact us with questions or comments. And, we always
appreciate hearing about successful projects you have completed.

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is designed to provide the detailed, transparent sonic performance

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has special features

OVERVIEW

In addition to our acclaimed TRUE preamps, P2
inputs (DI’s) that offer sonic performance previously thought to be available only with
dedicated, high-end DI’s. You’ll get incredible articulation and control for electric bass,
detail and smoothness for stringed instruments and keyboards. And, there’s even an
impedance modification option to help you get the most out of your vintage Strat!

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features two instrument direct

Even with today’s emphasis on powerful digital audio platforms and software plug-ins to
perform signal-processing tasks, the issue of microphone placement remains a critical
variable in determining the quality of your final sonic product. The P2
incorporates powerful features that assist you in achieving optimum microphone
placement for nearly any stereo recording situation. One of these features is a
selectable M-S (Mid-Side) decoder which provides creative spatial control that is useful
in attaining an exciting stereo image with minimum effort and microphone repositioning.
The M-S microphone technique can be employed effectively in a wide variety of
circumstances, from classical ensemble, to drum kit overheads, to solo vocal or
instrument – whenever accurate capture of the performance and its acoustical space is
desired. M-S micing also eliminates the “hole-in-the-middle” effect.

And, whether using M-S, X-Y or other stereo mic techniques, our Stereo Phase
Correlation Display can assist in positioning the microphones for a rich stereo image.

In addition to the previously mentioned features, the P2

 Dual Gain Ranges - to accommodate a wide range of microphone sensitivities
 Selectable High-Pass Filters - to minimize breath and wind noise
 Relay Signal Switching - to provide the cleanest possible signal path
 Polarity Reverse - to correct polarity inversions caused by mic position or cable

wiring variations

 XLR and TRS output connectors - for easy connectivity
 Phantom Power (48V)

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includes:

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P2

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MID

SIDE

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OPERATION MANUAL

UP-AND-RUNNING IN A HURRY

1. Read the “SAFETY and OPERATING PRECAUTIONS”on page 2 of this manual.

2. Check the voltage selector on the rear panel to make sure it is set for the

appropriate AC mains voltage in your area.

3. After making sure the main power switch is off, connect the AC power cord.

4. Connect output signal cables between P2

your recorder, mixer, signal processor, etc. Use either the 1/4” TRS or XLR balanced
output connectors. See the section “Connections” for wiring details.

5. Connect mic cables to MIC 1 and MIC 2 as needed.

6. Turn on the AC power.

7. Select 48V and 180polarity) buttons as appropriate on each channel.

8. Adjust Channel 1 and Channel 2 gain controls for adequate signal level as indicated

on the P2
is connected.

If you’re using the DI’s for electric instrument input:

1. Connect your instrument cables to DI-1 and/or DI-2 on the front panel. Any
microphones plugged into MIC1 or MIC2 will be automatically de-selected.
NOTE: DO NOT use TRS plugs for these inputs as the DI will not function correctly.

2. Select 180polarity) buttons as appropriate.

3. Adjust Channel 1 or Channel 2 gain controls for adequate signal level as indicated

on the P2analog level indicators or on the level indicators of the device to which it is
connected.

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level indicators or on the level indicators of the device to which it

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and the analog line level inputs of

If you’re using the M-S Decoder:

1. Connect the cardioid or omni MID mic to MIC 1 input.

2. Connect the figure 8 SIDE mic to MIC 2 input. Face the SIDE mic toward the left

side of the sound field (perpendicular to the axis of the MID mic). See Figure 1.

3. Press the M-S button to select the Mid-Side Mode. “Left” signal is routed to Channel
1 output. “Right” signal is routed to Channel 2 output.

4. Adjust the Channel 1 gain control for adequate mono signal level.

5. Adjust the Channel 2 gain control to vary the image width as desired.

6. See the section “More About M-S Decoding” for more information.

Figure 1

M-S microphone orientation

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Using the Stereo Phase Correlation Display

If you wish to use the Stereo Phase Correlation Display to assist with stereo mic
positioning:

1. Press the ON/OFF button to activate the display.

2. Adjust microphone positions so that most display activity occurs in the yellow and

green LED’s, with minimal activity in the red LED’s. See the section “Stereo Phase
Correlation Display” for more information.

3. NOTE: The Stereo Phase Correlation Display is intended for use with stereo mic
placement techniques. The display may not provide meaningful information for
independent, two-channel applications.

OPERATION MANUAL

INSTALLATION

Unpacking and Inspection

We recommend that you inspect your P2
shipping carton. In the unlikely event that the unit exhibits any physical damage, DO
NOT connect it to the AC mains power, but contact your dealer immediately.

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upon unpacking it from the factory

In addition to the P2

An AC power cord
A warranty registration card
A “Caution” sheet
This Operation Manual

We recommend that you keep the shipping carton and foam supports in the event that
the unit must be shipped at some time in the future. DO NOT package the unit in
“packing peanuts” or similar material as it will settle during shipping and damage will
likely occur. If original packing materials cannot be located, wrap the unit with a liberal
amount of plastic “bubble wrap” material extending at least 2” beyond the extremities of
the P2

Mounting

The P2
use of the adhesive rubber feet supplied. Avoid locating the unit next to equipment that
emits strong electromagnetic fields. If the unit is to be permanently mounted in a high­vibration environment, you may wish to provide additional side or rear support to
prevent possible distortion of the mounting ears.

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enclosure.

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 Do not locate the unit where it is exposed to rain, moisture, or liquid spills.
 Do not locate the unit where it is exposed to temperature extremes.

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is designed for conventional rack mounting, or stand-alone mounting by

, the shipping carton should also include:

P2

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MIC 1

MIC 2

OUT 1

OUT 2MS BALANCED

ANALOG OUTS

LINK

RISK OF ELECTRIC SHOCK

DO NOT OPEN

TRUE Systems - P2

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PIN 2 +

PIN 3 -

SUNRISE ENGINEERING AND DESIGN INC.

OUT 2

OUT 1

TUCSON, ARIZONA U.S.A.

For contin u e d p ro t e ct ion a g a in st f ire

replace o n ly w ith s ame type fuse:

115 T 3 1 5 mA L , 250V

230 T 16 0 m A L , 250V

CAUTION

ATTENTION

RISQUE DE CHOC ELECTRIQUE

- NE PAS OVRIR

This device complies with Part 15 of the FC C Ru les.

Operation is subject to the following two co nditions:

(1) this device may not cause harm fu l interferen ce,

and (2) this device must accept any interference that

may cause undesired operation.

115/230 V

50/60 Hz, 22W

115

21364

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OPERATION MANUAL

Ventilation

We recommend that you provide adequate ventilation so that the air temperature
surrounding the unit does not exceed 55C (122F). If multiple units are to be mounted

in a poorly ventilated rack or travel case, a 1 3/4” blank space should be located after
every three units (three units mounted together, blank space, three more units, etc.).

OPERATION

Connections

AC Mains Connection: Prior to connecting the AC mains power cord, verify
that the Voltage Selector switch 1 on the rear panel is set for the AC mains
voltage in your area.

Voltage Selector Position Operating Voltage Range Fuses (2)

115V 100-132VAC 50/60Hz T 315mA L, 250V
230V 200-264VAC 50/60Hz T 160mA L, 250V

For other operating voltage options, consult TRUE Systems.

CAUTION: To provide continued protection against fire, replacement fuses
should be only of the types listed above. AC mains power cord must be
removed to gain access to Fuse Drawer 2 for fuse replacement.

The Signal Ground LINK 3 connects signal ground to earth ground. Signal ground is
isolated from earth ground if the LINK jumper is removed. This jumper will normally be
installed. See “Troubleshooting” section for usage tips.

Microphone Connection: Microphone connection is made to standard XLR receptacles
4 on the rear panel. The wiring configuration used for the microphone connectors on
the P2

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is:

 Pin 2 is positive (+)
 Pin 3 is negative (-)
 Pin 1 is shield

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Do not attempt to connect unbalanced microphones (with single-pin connectors) to the

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You may note the M-S (mid-side) connection symbol 5 below the MIC 1 and MIC 2
connectors. This is simply a visual reminder, when using an M-S mic setup, to connect
the MID mic to channel 1 and the SIDE mic to channel 2. See the section “More About
M-S Decoding” for more information.

may result in transients that can damage the P2
to its outputs-not to mention your ears!

Output Cable Connection: For ease of connection, two styles of balanced output
connector (XLR and TRS) are provided 6 . Both connector types are electrically
equivalent and may be used simultaneously to connect to Line Inputs on mixing
consoles, recorders, etc. If both pairs of outputs are used, care should be taken to avoid
system ground loops. See “Troubleshooting” section for tips on avoiding hum caused
by grounding problems.

. It is not intended to operate with this type of microphone.

CAUTION: We recommend that you avoid “hot-patching” microphone inputs
when using a patch bay at the microphone inputs of the P2
TURN OFF phantom power and turn down the gain prior to connecting or re­patching microphone inputs routed through a patch bay.. Failure to do so

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or equipment that is connected

OPERATION MANUAL

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. Please

The TRS and XLR output connectors are not electronically isolated. Therefore, if you
chose to connect either one of the output connectors to an unbalanced input, the other
connector will automatically be unbalanced. When connecting an output of the

P2

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the XLR or “ring” of the TRS) to the shield. Failure to do this will result in audible
distortion. The wiring configuration used for the output connectors on the P2

A Word About Cables.....

Most users of the P2
microphones and preamplifiers. We recommend that you give some consideration to the
microphone, instrument and output cables you select, as well.

 Use high-quality, low capacitance cable. Braided shielding and “star quad” type mic

cables will perform better in electrically noisy environments. Manufacturers such as
Canare, Mogami (and others) make high performance cable of this type.

 Some “house brand” cables are made by quality manufacturers, but others can be

inferior. Be careful. Use cables with high-quality connectors (Neutrik, Switchcraft,
etc.).

to an unbalanced input, you must connect the negative signal pin (pin 3 of

For XLR:

 Pin 2 is positive (+)
 Pin 3 is negative (-)
 Pin 1 is shield

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have invested much time and money in their selection of

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For TRS:

 Tip is positive (+)
 Ring is negative (-)
 Sleeve is shield

is:

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+24

SIG

+21

+18

+15

+12

+4

48V

HPF

GAIN

80HZ

40HZ

OL

1

2

DI-1

DI-2

TRUE

systems

180

o

123

MID

SIDE

In M-S Mode:

Gain 1 adjusts Mono signal level

Gain 2 adjusts Stereo image width

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OPERATION MANUAL

 Our studio testing has shown that some of the more esoteric guitar/instrument

“super-cables” do, indeed, sound better. Noticeable improvement, but at a stiff price.
Try before you buy!

 Avoid excessive cable length.
 Replace damaged connectors.

Front Panel Controls

1 DI-1 and/or DI-2 connectors are used to connect electric instrument pickups to

channel 1 or channel 2 of the P2

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. Any microphones plugged into MIC1 or

MIC2 will be automatically de-selected. Direct inputs DI-1 and DI-2 are controlled by

gain controls for channels 1 and 2, respectively. Input selections for GAIN, HPF, and
Polarity (180) apply to the DI inputs in the same manner as they apply to MIC

inputs. See below for explanation of these functions. The gain range for the direct
inputs is from -4 dB to +44 dB at normal gain (GAIN indicator ON) and -16 to +32dB
at low gain (GAIN indicator OFF).

NOTE: DO NOT use TRS plugs for these inputs as the DI will not function correctly.

2 Polarity reverse selector (180). Input signal polarity is reversed when the 180

indicator is illuminated. Use this to reverse input polarity to correct for microphone
position or cable wiring differences.

3 High Pass Filter selector (HPF). Use this to reduce undesirable low frequency wind,

stage or handling noise. In general, the 40Hz setting is appropriate for musical
sources and the 80Hz setting is appropriate for voice. Note that use of the HPF will
most likely not eliminate the need for a pop screen for close-mic’d vocals.

4 Gain range selector (GAIN). Use this to select the appropriate gain range. This

selector can be thought of as a “pad” although it does not have any sonic impact as

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STEREO PHASE CORRELA T ION

090180

M-S

ON/OFF

P2

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2-channel microphone pream plifier

I

0

7

8

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OPERATION MANUAL

can happen with a conventional pad circuit. Normal microphone gain range (15.5dB
to 64dB) is selected when the indicator is ON. Low gain range (3.5dB to 52dB) is
selected when the indicator is OFF.

5 Phantom power selector (48V). Phantom power (+48VDC) is activated when the 48V

indicator is illuminated. Avoid selecting phantom power if you are using a ribbon
microphone. While not required, it is advisable to de-select 48V when using a
dynamic microphone or a DI input.

6 Level indicators. Use these to match signal level between the P2

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and

devices to which it is connected - and to avoid overloading the preamp.

 SIG indicates that a signal is present on the channel. It illuminates when the signal

level exceeds -24dBu.

 +4 illuminates when the signal reaches normal operating level of +4 dBu.
 OL illuminates when the signal level exceeds +26 dBu, which is 5 dB below the

overload point for the P2

 .Note that the overload level of the P2

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*.

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is +31dBu at the output*. This level
exceeds the input capability of some devices (check manufacturer’s specifications).
In such cases it is appropriate to use the intermediate level indicators (+15, +18,
+21, +24) to set the maximum output level of the P2

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to match the maximum
input capability of the connected device. In other words, it is possible to cause
overload distortion in the connected device even though the P2

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level
indicator does not show a red light. * Maximum output level in the low gain range is
+27dBu.

7 Mid-Side mode selector (M-S). When the M-S indicator is ON, Channel 1 output

becomes “Left” and Channel 2 output becomes “Right”. The Channel 1 gain control
adjusts the mono signal level applied to both the Left and Right outputs. The
Channel 2 gain control adjusts the stereo image width.

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MID

SIDE

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NOTE: When M-S is selected, GAIN and polarity (180) are set to normal on both
Channel 1 and Channel 2. The GAIN selectors for both channels are “locked”
together so that pressing either one causes a similar gain range setting in both
channels.

8 The Stereo Phase Correlation display selector (ON/OFF) determines whether the

LED display is illuminated or not. In some circumstances the display can be very
active or distracting. This selector allows you to simply de-activate the display. See
the section “Stereo Phase Correlation Display” for more information.

Direct Inputs

The Direct Inputs (DI’s) are used for connection of electric instrument pickups or
unbalanced sources such as synthesizers. The DI’s we’ve designed for the P2
match (or exceed) the sonic performance of acclaimed, dedicated DI products. They
provide excellent articulation and control for electric/acoustic bass, detail and
smoothness for stringed instruments and keyboards. Simply plug the instrument cable
into the front panel DI-1 or DI-2 connector. When an instrument is connected to the DI
input, it overrides the microphone connection. Here are some tips for using the DI’s:
 The HPF may, in some cases, be used to produce useful tonal variations. See the

“Front Panel Controls” section for more information.

 If you have an instrument with two pickup outputs available, you may want to try

using the M-S mode to obtain interesting image or tonal variations.

 As some guitarists know, certain instruments produce a desirable tone when the

pickups are terminated with a specific resistance/impedance value. While the input
impedance of the P2
capability to modify the input impedance for a specific application. Since this
modification requires opening the product enclosure, it should only be performed by
qualified technical personnel. Contact TRUE Systems Technical Support for more
information.

 Use only ¼” unbalanced (tip/sleeve) plugs to connect to the DI. See the “Front Panel

Controls” section for more information.

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is quite high (2.5 megohms), we’ve provided the

OPERATION MANUAL

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More About M-S Decoding:

M-S (Mid-Side) decoding is a particularly creative feature of the P2
M-S microphone technique has been around for many years, the opportunity to use it is
frequently limited by the need for specialty microphones and/or decoders.

What is M-S?
It is a stereo microphone placement technique
that uses a center, forward-facing omni or
cardioid mic (Mid) and a side-facing figure 8 mic
(Side). The signals from these two mics are
passed through matrix circuitry that combines
them in particular phase and level relationships to
produce a stereo L and R output.

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. While the

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What good is M-S versus the typical XY microphone placement?
Originally, M-S was used because it provided a stereo signal with good mono
compatibility. While this is not very interesting for contemporary stereo CD’s, it is still
valuable for broadcast and film sound production. But there is another significant
benefit: varying the gain of the Side mic in relation to the Mid mic causes a variation in
the stereo image - from none, to extreme separation. It is not necessary to change the
angle or position of the microphones in order to change the stereo image. This feature
can really speed up the time-consuming process of finding a “sweet spot” that provides
both good tonal quality and good imaging.

What are the best applications for M-S?
M-S does an excellent job of capturing the natural sonic perspective of acoustical
ensembles.

 Orchestral and choral recording: use an M-S pair for the central array
 Drum kits: use an M-S pair for drum overhead micing.
 Vocal and instrumental ensembles: use M-S to give realistic perspective to backup

vocals or instrumental groups.

 Individual instruments or vocals: try M-S on acoustic guitar and in situations where

you wish to capture room ambience.

 Broadcast/film sound: use M-S to capture audience noise or background ambience.

M-S can also be used in TV and film work to match the sonic image width to the
visual image width.

OPERATION MANUAL

Stereo Phase Correlation Display

The Stereo Phase Correlation circuit “listens” to the two preamp outputs in the
frequency range where human hearing is most sensitive to audio phase information. It
analyzes the phase information and displays the following conditions:

 Output signals are essentially mono
 Output signals exhibit phase information that indicates a good stereo image
 Output contains too much out-of-phase information, producing tonal variance or

muddiness (Adjust the microphone positions)

 Outputs are completely out-of-phase. (Select the “180” polarity reverse on one

channel)

The Stereo Phase Correlation Display is also useful when placing two mics on an
instrument (for instance, acoustic guitar) to achieve a particular tonal effect. The Phase
Display will show any phase errors that produce a comb-filtering effect, allowing you to
interactively adjust the microphone position for optimum sound.

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STEREO PHASE CORRELATION

090180

STEREO PHASE CORRELATION

090180

STEREO PHASE CORRELATION

090180

STEREO PHASE CORRELATION

090180

Outpu t signals are essen tially MO N O

T ypical STEREO display

Excessive PHAS E ERRO RS

(Adjust microphone)

POLARITY REVERSA L

(Reverse po larity on one microph on e)

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OPERATION MANUAL

Here are some tips for using the Stereo Phase Correlation Display:
 When attempting to get a good stereo image, position the mics so that most of the

Phase Display intensity is centered around the middle (yellow) range.

 The Stereo Phase Correlation Display should not be thought of in the same way that

you think of a Level Indicator. In general, we don’t want to see a RED Level Indicator
because it means we’re going to get distortion. But, with the Phase Display, some
amount of “red activity” is normal when we have an acceptable stereo image. This
happens because there is a mix of various phase information in any complex audio
signal (music, voice). Conversely, an “all green” display is “safe” in that it shows
minimal out-of-phase information, but, for the same reason, the output signals will
not exhibit much of a stereo image.

 You may want to become familiar with the Phase Display by observing its activity in

known situations. That is, situations where you know from experience that you have
good mic positioning and stereo image. Also, observe the Phase Display in
situations that you know will produce poor sonic outcome.

 The Stereo Phase Correlation Display is intended for use with stereo mic placement

techniques. The Display may not provide meaningful information for independent,
two-channel applications.

 When using the M-S mode it is unlikely that you will see a Polarity Reversal situation

as illustrated in the figure above. However, a right/left reversal may occur due to
wiring variations or reversed orientation of the SIDE mic. This can be corrected by
selecting 180 on Channel 2.

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 As always, your ears are the final reference! The Stereo Phase Correlation Display

is provided as an accessory to help you with a potentially difficult and subjective part
of the recording/sound reinforcement process. But when all is said and done, what
you hear is more important than what you see on this Display.

 The Phase Display can become quite “busy” with complex sound sources. After mic

positioning has been determined, you may wish to turn off the flickering Display.
We’ve provided the ON/OFF selector for that purpose.

OPERATION MANUAL

DESIGN APPROACH

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integrated circuits. The totally balanced, dual servo, dc-coupled design provides
exceptional transient response, headroom, imaging and noise performance. Military
grade, hand-matched components are utilized in critical circuit areas. All signal
switching is done via hi-rel gold-contact relays in order to maintain an extremely short
signal path. These design features result in the transparent, detailed sound quality for
which TRUE preamps have become known.

features a high-voltage composite architecture with discrete devices plus

SPECIFICATIONS

Gain, preamp: 3.5 to 52dB and 15.5 to 64dB (dual range)
DI: -16 to 32dB and –4 to 44dB

Frequency Response: 1.5 Hz to 500kHz (-3dB)
(gain=40dB)

Maximum Output Level: +31 dBu (+27 dBu in low gain mode)
Maximum Input Level: +15 dBu (+25 dBu in low gain mode)
Noise (Rs=0 Ohms): -132 dB e.i.n.
Slew Rate: >40 V/uS
CMRR (CMV= +10 dBu): 85 dB
THD (preamp) (+26dBu, 100kOhm) .0008%
Input Impedance, preamp: 5.5 Kohm

DI: 2.5 Mohm (impedance modification available)
Power Consumption: 22W
Enclosure Dimensions: 17.5 in. (44.5 cm) W, 13.75 in. (35cm) D,

1.75 in. (4.5cm) H
Front Panel Extension: 1 in. (2.5cm)
Weight: 15 lbs. (6.8kg)

Typical performance. Specifications subject to change without notice.

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Symptom

No signal output. Main power switch
is on, but no LED’s are illuminated.

Solution

 Check AC power source and cord.
 Check fuses (pull fuse drawer under power

cord inlet)

No signal output. Main power switch
is on and some LED’s are
illuminated.

 Check status of phantom power.
 Check continuity of mic and electric

instrument cables.

 Check continuity of output cables.
Output signal is distorted. Outputs

are connected for balanced
operation.

 Make sure gain is adjusted so that the OL

indicator does not activate during the audio
program.

 Make sure the high output capability of this

unit is not overloading the device or
monitoring system to which it is connected ­set GAIN selector to match capability of
device or monitoring system, then adjust gain
control according to indications on the Level
Indicator LED’s.

 Check continuity of output cable.
 Make sure outputs are not connected to a

load impedance of less than 600 ohms.

Output signal is distorted. Outputs
are connected for unbalanced
operation.

 Make sure the minus (-) output signal pins are

connected to the shield and not left
unconnected. See “Output Cable Connection”
section.

 Check troubleshooting tips for balanced

operation (above).

Hum can be heard in the audio
program.

 Disconnect grounding LINK.
 Check continuity of output cables (particularly

shields).

 Disconnect shields on one end of output

cables. Connect grounding LINK.

Channel 1 signal can be heard in
Channel 2 output - and vice versa.

 Check status of M-S selector. It should be

OFF for individual channel mode and ON for
Mid-Side mode.

Channel 2 seems to have no output

 Check status of M-S selector. It should be

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TROUBLESHOOTING

OPERATION MANUAL

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when used with Channel 1 as a
stereo pair

OFF for individual channel mode and ON for
Mid-Side mode.

 Make sure the 180selectors for both

Channels 1 and 2 are OFF.

In M-S mode the stereo channels
are reversed (Channel 1 is Right
and Channel 2 is Left)

 Make sure the front of the bi-directional “Side”

mic is aimed 90 degrees to the left of the axis
of the “Mid” mic. Alternatively, select 180 on
Channel 2 to reverse channel positions.

In M-S mode the stereo channel
phasing is incorrect

 Make sure the 180selectors for both

Channels 1 and 2 are in the same position.

Electric instrument connected to a
Direct Input does not produce a
signal or signal is distorted.

 Check continuity of electric instrument cables.
 Check the batteries or AC power source of

any “foot pedal” effects processors connected
to the Direct Input.

 Make sure that the instrument cables have

standard tip-sleeve 1/4” phone plugs. - DO
NOT use TRS plugs.

Radio Frequency Interference can
be heard in the audio program
(swishing sound or audio from a
radio transmitter).

 Make sure that mic cables are of good quality

and that the shield is properly connected.
Avoid excessive length.

 Make sure that earth ground connection is

maintained via the AC power cord - DO NOT
use an isolator.

 Make sure the unit is located away from

known sources of radio frequency energy.

.

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OPERATION MANUAL

REGISTRATION and WARRANTY

Don’t forget to register your P2
returning it to us. This allows TRUE Systems to contact you regarding any updates,
upgrades or applications information that may become available.

SUNRISE ENGINEERING and DESIGN INC. (“SUNRISE”) warrants the TRUE

systems P2

properly installed and used according to instructions in the Operation Manual, for a
period of one year from the date of sale to the original purchaser. Units returned for
warranty repair to SUNRISE or an authorized TRUE Systems repair facility will be
repaired or replaced at the manufacturer’s option, free of charge. Supplementary
shipping charges will apply to units returned to addresses outside the continental USA.
All units returned to SUNRISE or authorized TRUE systems repair facility must be
prepaid, insured and properly packaged. Purchaser must obtain a Return Material

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to be free from defects in material and manufacture, when

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by filling out the enclosed Registration Card and

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Authorization (RMA) number from SUNRISE prior to returning a product. SUNRISE may
require proof of the purchase date in the form of a copy of a dated original retail invoice.

This warranty is void if, in the sole judgment of SUNRISE, the product has been
abused, neglected, misapplied, or has been damaged by an accident, modification, or
attempted repair by unauthorized personnel. This warranty will not apply to cosmetic
damage incurred due to normal handling and use. SUNRISE reserves the right to
change or improve the product design at any time without prior notice. Incorporation of
design changes in future versions of the product does not imply the availability of
upgrades for existing units.

This warranty is in lieu of all other warranties, expressed or implied, and SUNRISE
specifically disclaims all implied warranties, including, but not limited to, warranties of
merchantability and fitness for a particular purpose. The purchaser acknowledges and
agrees that in no event shall SUNRISE be held liable for any special, indirect, incidental
or consequential damage, or for injury, loss or damage sustained by any person or
property, that may result from the use of, or failure of this product to operate correctly at
any time. In the USA, some states do not allow the exclusion or limitation of implied
warranties or liability for incidental or consequential damage, so the previous exclusion
may not apply to you. This warranty gives you specific legal rights, and you may have
other rights that vary from state to state.

OPERATION MANUAL

SERVICE and SUPPORT INFORMATION

 Registered users may obtain customer support by calling [phone]. Please

ask for Tech Support. You may also visit our website: www.true-systems.com or
email us at: [e-mail].

 Other than cleaning the exterior surfaces of your P2

inspection of the AC power cord and audio cables for damage, no maintenance
procedures should be attempted by the user. Exterior cleaning can be performed
using a lint-free cloth dampened with Windex or equivalent.

There are no user-serviceable components inside the product enclosure.
Many of the electronic components are selected and matched at the factory.

For this reason, as well as personal safety considerations, we recommend
that you refer servicing to TRUE Systems. If you choose to have repairs performed by
other qualified service personnel, we recommend they contact us prior to performing
repairs. We will be happy to advise them of any special repair considerations.

All units returned to SUNRISE or authorized TRUE systems repair facility must be
prepaid, insured and properly packaged. Purchaser must obtain a Return Material
Authorization (RMA) number prior to returning a product.

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and occasional

Sunrise Engineering and Design Inc. Tel: [phone]
1634 S. Research Loop, Suite 110 Fax: [phone]
Tucson, Arizona 85710 USA Email: [e-mail]