Sound Performance Lab EQ MAGIX User Manual

SOUND PERFORMANCE LABORATORY
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SOUND PERFORMANCE LABORATORY
EQ MAGIX Owner´s Manual by Hermann Gier
Manual version 2.1/94
Construction and circuit layout are subject to constant improve­ment and development.
Changes will be made without notice.
©
1994 SPL electronics GmbH All rights reserved
® 1993 Vitalizer is a registered trademark of SPL electronics GmbH
SPL electronics GmbH Sohlweg 55
D-41372 Niederkrüchten Germany
Tel. (0 21 63) 98 34-0 Fax (0 21 63) 98 34-20
3
Contents
Foreword 4 Introduction 4
The concept of sound processing in the EQ MAGIX 7
Installation 9 Inputs & outputs 9 Power supply 10 Rear panel 11 Connection examples 11
Control elements
Input Mic /Line 12
Line -30dB 12 Peak 13 Phase reverse 13 48V phantom power supply 13 Insert 14
Parametric Active 15
Frequency 15 Boost/Cut (+/-) 16 Bandwidth Q 17 Q Fine 17 Notch 17 Deleting an interference frequeny 19
Introduction into the Vitalizer 20 The control elements of the Vitalizer
Active 22 +10dB 22 Peak 22 Bass 23 Deep 24 Mid-Hi Tune 24 Process 25 Harmonics 26 Combine 26
Output Pan 27
PPM Meter 27 Fader 27 Mute 27
Specifications 28 Block diagram 29 Circuit layout 30 Main board & top board 32
EQ MAGIX legend 33
Warranty 34
4
Dear customer,
Thank you for the confidence you have shown towards SPL electronics GmbH by purchasing the SPL EQ MAGIX. The EQ MAGIX is a first-rate Equalizer with exemplary specifications, excellent workmanship and unri­valled sound quality.
Please study this owner´s manual carefully so that you can make the most of the wide range of possible applications offered by the EQ MAGIX and to ensure ease of operation.
We have tried to write this manual in such a way that it is easy to under­stand, with as clear a layout as the complexity of such a sophisticated product allows. The manual is divided into two columns throughout. The main column contains a detailed description whilst the margin contains headings and summarized information.
We wish you every success and unlimited enjoyment with your new EQ MAGIX.
SOUND PERFORMANCE LABORATORY SPL electronics GmbH
The EQ MAGIX is a single-channel equalizer system consisting of a para­metric and a psychoacoustic equalizer. Both are combined with a superior microphone preamplifier and an active two-channel panorama output stage.
People in MIDI hybrid studios or production studios often need a single mixing desk channel with superior microphone preamplification and perfect sound control to record different song tracks, saxophone or guitar soli on R-Dat, hard disk or samplers. The EQ MAGIX is, so to speak, an »all-in-one« tool for applications of this nature.
The EQ MAGIX is ideally suited for both a demanding instrumentalist's or a singer's rack. Existing equipment can be looped into the signal path via I
NSERT. The unit's outputs are either connected directly with the recording
medium or with one to four (2x balanced and 2x unbalanced) mixing desk channels. From there, the signal is fed into the Insert Return after the EQ section (provided that appropriate Insert points are available), so as to bypass as much desk circuitry as possible. As you know, a signal is also influenced if all the switches are on »off« and all controls are in the centre position or on »0«. That is why it is advisable to feed the signal in after the desk equalizer.
The technology in the microphone preamplifier is used in the very latest generation of mixing desks made by Harrison and SSL. The P
ARAMETRIC
Foreword
Introduction
5
The
II
NNPPUUTT
section features a microphone preamplifier with 48V phantom power supply, P
HASEREVERSE
and L
INE
-30 dB
switch, P
EAK
indicator
II
NNSSEERRTT
jacks between
microphone preamplifier and
PARAMETRIC
equalizer.
PP
AARRAAMMEETTRRIICC
equalizer with a frequency range from 14 Hz to 58 kHz, constant-Q, Q-F
INE
switch,
+/-15dB B
OOST/CUT
,
N
OTCH
with R
OLL-OFF
equalizer of the EQ MAGIX is based on SVF design (state-variable-filter) and provides a operation frequency range between 14 Hz and 58 kHz. The integrated V
ITALIZER was developed by SPL and has achieved a significant
degree of popularity over the years. The filter concept works on the basis of psychoacoustic sound principles and is therefore ideal to achieve creative sound effects.
The combination of a flexible parametric EQ and V
ITALIZER means that
the EQ MAGIX is not only predestined to process the sounds of acoustic instruments but also to post-process samples or poor quality Sync audio tracks, ranging from the elimination of aliasing artefacts or other digital interferences to the addition of sub basses or comprehensive sound impro­vements via the V
ITALIZER.
The EQ MAGIX provides you with equalizer technology which is unri­valled in comparable units. You will find that this equalizer can not only be set quickly and accurately at the desired frequencies but, with the aid of loudness sound control, can also form sound patterns which cannot be achieved with conventional equalizers.
The section below contains a brief description of the EQ MAGIX's func­tion groups:
1.
II
NNPPUUTT
: Microphone and line level signals can be preamplified in the
I
NPUT section. Microphone signals can be preamplified up to 65 dB.
Activating the L
INE switch attenuates the preamplifiers stage by -30 dB.
There is a phantom power supply (48 V) for condensor microphones. The
P
HASE REVERSE switch is used to change the polarity of the microphone. The
P
EAK LED provides adequate warning of potential overdriving of the
output stages in the I
NPUT section.
2.
II
NNSSEERRTT
: Additional sound processing equipment such as a compressor,
de-esser or reverb can be looped into the EQ MAGIX via the I
NSERT jacks.
The I
NPUT section can be used separately for one signal, whilst the equa-
lizer sections are available for a second signal. Use the I
NSERT SEND as the
output for the I
NPUT section and the INSERT RETURN as the input for the
second signal.
3.
PP
AARRAAMMEETTRRIICC
: The PARAMETRIC equalizer is to boost or cut different frequencies or to cut out specific interference noise signals. It is, in a manner of speaking, a corrective instrument in the EQ MAGIX chain of sound-processing tools. The P
ARAMETRIC works according to the constant-Q
principle. The frequency ranges between 14 Hz and 58 kHz. The control characteristics of the bandwidth (Q) control ranges from Q0.6 to Q3.6 and can be sensitized via the Q-F
INE switch to set more subtle Q values. The
boost or cut range is max. +/-15dB. The integrated N
OTCH filter can be
controlled in frequency, bandwidth and also in the filter slope (R
OLL-OFF)
from gentle decreasing or increasing (G
ENTLE) to steeply decreasing or
increasing (S
TEEP). This significantly increases the tonal flexibility of the
N
OTCH Filter.
Introduction
6
4. VITALIZER®®: The VITALIZER is an equalizer concept which makes use of scientific psychoacoustic technology to process audio signals. The unique combination of dynamic equalizers, amplitude-controlled phase correction and harmonic filtering in the V
ITALIZER opens up a whole new listening
dimension by adapting the sound pattern to the non-linearities of the human ear. The V
ITALIZER is thus the creative element amongst the EQ
MAGIX's sound processing tools.
The V
ITALIZER gives the mid frequencies accurate transparency with a
soft, unobtrusive sound. The treble and harmonics range is reworked with broadband shelving filters of 2nd and 4th order, which focus on achieving a smooth, silky sound pattern. High frequencies are livened up without them sounding hard or agressive.
The V
ITALIZER uses a newly developed filter network to process the low
frequency range. The bass is accentuated without any risk of emphasizing the lower mid frequencies unnaturally. You can choose between a dry, percussive bass (T
IGHT) or a punchy, soft and very deep sound character
(S
OFT).
The result is a pleasanter and livelier sound pattern with an unrivalled wealth of detail. You will be amazed by how transparent and powerful almost every audio signal sounds after it has been processed with the V
ITALIZER!
5.
OO
UUTTPPUUTT
: The OUTPUT section enables you to create a two-channel output signal from a one-channel input signal. You can return the signal to two desk channels or feed it directly into a multi-track recording medium or effect unit. Balanced outputs available via XLR sockets and unbalanced outputs available via jacks can be used in parallel. A signal can therefore be recorded on two media simultaneously.
On the front panel, two bargraph meters each featuring 10 LEDs provide information about the output level of each channel. The indication of PPM values (peak values) provide more information than a VU display (average values). The M
UTE switch can be used to mute the output signal
altogether. The P
ANORAMA control allows
active
panning between the two output channels, compensating the loss in volume (- 3dB) which arises in conjunction with panning to one channel. The F
ADER switch alters the
characteristics of the P
ANORAMA control, making it an output level control.
The output level can be reduced for both channels to compensate diffe­rences in the levels of the processed and the dry signal.
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IITTAALLIIZZEERR
®®
iinn tthhee EEQQ MMAAGGIIXX:: The new generation of psycho­acoustic equalizers for the first time in a 19“ mixer channel module, together with microphone preamplifier,
PARAMETRIC
equalizer and
P
ANORAMA
output stage.
The
PP
AANNOORRAAMMAA
output stage creates a double Mono output signal from the Mono input signal and enables active panning between the two channels.
Two LED meters indicate the PPM peak values. M
UTE
and F
ADER
switch options.
Introduction
7
The concept of sound processing in the EQ MAGIX
The P
ARAMETRIC
section serves to perfectly remove any interference frequency or to accentuate a frequency band as desired.
With its enormous range of frequencies from 14 Hz to 58 kHz, the EQ MAGIX provides a plat­form for experimentation as to the extent signal portions affect the tonal perception range beyond the spectrum of the human hearing.
The EQ MAGIX features a PARAMETRIC constant-Q equaliser combined
with the V
ITALIZER equaliser system.
This combination of filters is based on the assumption that after succes­sful microphoning, you only have one problem zone, if at all, that needs to be equalized. The V
ITALIZER provides all the necessary circuitry for creative
sound post-processing.
The EQ MAGIX provides a total of five processing ranges: the PARAME­TRIC section provides an extremely variable and efficient filter for selective intervention in a frequency band between 14Hz and 58kHz. The VITA­LIZER interferes in 4 frequency ranges, bass, mid and treble, along with the harmonical frequencies pertaining to even and odd overtones.
The P
ARAMETRIC section is designed to clean up one »problem zone« in
the frequency spectrum of the recorded instrument or voice perfectly, without prejudicing the sound and without being inhibited by technical limitations of standardized filter circuits.
The equalizer used in the EQ MAGIX is based on the state-variable filter type (SVF). Its function is phase-stable and neutral right down to 14 Hz in the infra-sonic range. The frequency range extends right up to breath­taking 58 kHz! This initially provides a platform for experimentation as to whether interspersing digital components affects into the tonal perception range (16 Hz to 20 kHz) or whether the removal thereof can remedy sound problems directly or indirectly.
We have visited sound engineers and producers in European and American audio and video studios and they pointed out to us that inter­spersing the sample rate frequencies (44.1 kHz and 48 kHz) into the audio path is a well-known phenomenon, whereby subharmonic elements can be transposed right down into the audible frequency spectrum. Furthermore, this can result in audible phase shifts and distortions. With the EQ MAGIX, you can now influence these frequencies actively. The sample rate frequencies are inscribed on the scale (44, 48).
All frequencies can be boosted or cut with 15dB throughout the entire
frequency range from 14 Hz to 58 kHz. The P
ARAMETRIC equalizer of the EQ
MAGIX is based on the constant-Q principle and provides an »inversible Q«, i.e. when filtering out a interfering frequency, inverting the boost value to a cut value results in precise inversion of the bandwidth (Q) values.
Notching is also possible with a variable R
OLL-OFF to select a STEEP or
GENTLE filter slope.
Extremely flexible bandwidth defintion allows Q values between 0.6 and 3.6.
8
The VITALIZER is the creative sound component in the EQ MAGIX. It works »intelligently«, provided the appropriate parameters are preselected. This means that it does not just raise or lower a certain frequency range but analyses the signal and reacts to it, influencing the frequency and phase response in a sophisticated fashion.
Independently of the potentiometer settings on the front panel, the
V
ITALIZER filter system can correlate the phase and amplitude relations of
adjacent frequency bands in such a way that the increasing amplitude of a frequency is given a growing phase drift which, however, can never endanger the signal's mono compatibility. The maximum phase drift is +/­20° which equals a time difference of around 1 ms to 2.5 ms. This time span is sufficient to trigger two hearing perceptions. Quiet frequencies which are normally masked by louder ones are effectively demasked and thus become audible.
The front panel also accommodates controls to define the bass sound
colour (S
OFT/TIGHT), the starting frequency of the MID-HI TUNE filter, the
P
ROCESS intensity and the addition of the harmonics.
The B
ASS control provides up to 20 dB gain, thus affecting the direction
of the phase drift by the bass sound colour selected. The fact that the phase drift is controlled by the amplitude means that even high bass amplifica­tion remains free from negative sound colouration in the lower mid range.
The mid-high frequency filter (M
ID-HI TUNE) works with shelving filters
which provide »linear« broadband amplification. This rules out any comb filter effects which create sound distortions similar to those produced by graphic equalizers.
The P
ROCESS control determines the addition of the bass sound selected
and the M
ID-HI TUNE filter to the dry signal. In addition, dominant mid
frequencies are lowered by phase shifts which means that as the P
ROCESS
value increases, they are adapted automatically to curves of equal loudness (Fletcher-Munson curves). The P
ROCESS is, in a manner of spea-
king, an »intelligent« loudness control which can be used to set the typical »bath-tub« curves on graphic EQ's by turning one potentiometer.
The H
ARMONICS circuitry provides a silky sounding, refreshed version of
the original signal. This proves particularly beneficial for voices and acoustic instruments. No distortions are added to the original as there is no Exciter involved. The filters merely amplify the harmonic tones contained in the original.
The EQ MAGIX is constructed like a mixing desk channel. Direct recor­dings can be made on to a recording medium (multi-track machine or hard disk) which means that one less mixer channel is required.
The V
ITALIZER
is the creative sound
component in the EQ MAGIX.
The internal signal processing of the V
ITALIZER
correlates the phase with the amplitude in such a way that masking effects in the original signal are compensated.
The bass sound colours: S
OFT
& T
IGHT
The MID-HIT
UNE
filter provides shelving filtering with a broad bandwidth which therefore sounds very neutral.
The P
ROCESS
control adapts the output signal to the curves of equal loudness, thus realizing an intelligent loudness concept.
The H
ARMONICS
filter stage accen-
tuates even and odd harmonics.
The concept of sound processing in the EQ MAGIX
9
The housing of the EQ MAGIX has the standard 19" EIA format and
occupies 1 height unit (1 U = 44 mm) in your rack.
When installing the unit in a 19" rack, the rear side of the unit needs
some support, especially in a Touring Case.
The EQ MAGIX should not be installed near units which produce strong magnetic fields or extreme heat. Do not install the EQ MAGIX directly above or below power amplifiers or digital processors. If possible, the EQ MAGIX should be placed in an »analog rack« where the majority of (or all) the equipment installed is analog. This eliminates problems which could result from interfering high-frequency signals such as clock frequencies, MIDI or SMPTE control signals.
Make sure that the correct mains voltage has been set on the mains
voltage selector located at the rear of the EQ MAGIX.
The EQ MAGIX is equipped with an electronically balanced, 3-pole XLR socket to connect a microphone or a line signal.
The outputs of the EQ MAGIX are designed balanced on XLR sockets as well as unbalanced on 1/4“ jacks. The outputs can be used parallel to each other. This means that four output signals can be produced from one input signal.
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In addition, the EQ MAGIX also has unbalanced I
NSERT jacks which inter-
rupt the signal flow between the microphone preamplifier and the
PARAME-
TRIC equalizer.
The I
NSERT SEND jack can also be used as an output of the microphone
preamplifier. The I
NSERT RETURN jack can then pick up an independent
signal which means that two signals can be processed in parallel to each other. One signal uses the microphone preamplifier and another signal is processed by the EQ MAGIX equalizer.
Fig. 1: The diagram shows how to unbalance balanced wiring correctly
Installation
Inputs & Outputs
10
Special attention has been paid to the power supply of the EQ MAGIX. The power pack is the heart of any unit, and the more accurately it works, the more this improves results.
The power supply is installed around a toroidal-core transformer which does not cause any electronic humming or mechanical sounds as a result of its minimum leakage field. The primary voltage can be switched between 230 V / 50 Hz and 115 V / 60 Hz.
A 3-pole standard IEC mains connection socket serves to connect a detachable 3-pole mains lead which is included in the scope of supply. Transformer, power cable and mains connector comply with the require­ments of VDE, UL and CSA. The fuse rating is 200 mA.
The connection between ground and housing can be separated via the
G
ND LIFT switching option. Hum loops can be remedied in this way. Eloxal
has been removed from the back of the »ears« which serve to attach the unit in a 19" rack, in order to achieve 100% contact to the rack rail, in case the rack rail is used as a central ground. If the mains ground is inadequate, an alternative connection for the ground can be obtained via the binding post after activating the G
ND LIFT switch.
On the secondary side of the power supply, an RC combination is used to filter out noise and hum voltages from the mains side. Both half-waves are smoothed with 4700 µF capacitors in the positive and negative voltage path. Both pathes are calibrated separately via trimmers, as deviations of only a few millivolts can result in audible changes such as a diffuse sound pattern. After the calibration stage, the current is again smoothed.
Service voltage is raised gradually when the unit is switched on. This prevents voltage peaks (e.g. switch-on cracks) affecting the operational amplifiers. This safety circuit in turn prolongs the service life of the unit. Safety diodes also ensure that the power pack is not damaged if there is a short circuit within an IC.
An independent, self-contained power pack is used for the phantom power supply. It obtains unregulated AC voltage from 2 x 25 V coils in the transformer. This results in +/- 22.5 V DC via bridge rectifiers which are filtered with 1000µF. The DC voltage is adjusted to exactly 48 V in the switching power supply (LM 311) downstream. It is then smoothed again and stabilized. The power supply current flows to the intrusion point via the PCB. An RC combination stabilizes the power supply again at this point. Two medicinal 6.81 kresistors with a tolerance of only 0.1% are used as bridging resistors.
A stable and well-filtered toro­idal-core power supply provides the basis for good sound proces­sing.
The GND Lift switching option helps remedy hum loops.
A binding post permits connection of an alternative circuit ground.
Ample filtering, smoothings and calibrations make for stable, constant service voltage.
Protective circuitry prevents premature aging or damage to components.
The phantom supply voltage is from a separate power supply with sophisticated filtering and selected components.
Power supply
11
Rear panel
EEQQ MMAAGGIIXX rreeaarr ppaanneell
electronically balanced mic/line input; pin 2 = hot / pin 3 = cold unbalanced I
NSERT SEND/RETURN jacks
outputs: XLR (balanced, +6dB) and jack (unbalanced, 0dB) mains voltage selector: 220-240V / 50Hz or 100-120V / 60Hz G
ND LIFT switch and binding post for alternative ground connection
mains inlet connector for non-heating appliances with detachable 3-pole mains cable
Connection
examples
Microphone:
Announcer or singer, acoustic instrument Guitar amp miking
Insert Send/Return:
The microphone signal can be looped through other processors (e.g. compressor, limiter, reverb or effects unit).
The signal can be recorded directly onto one or two tracks of a multi­track recorder
The EQ MAGIX output signal can be fed into one or two insert returns of a mixing desk.
GND LIFT helps to prevent hum loops.
An alternative ground connection can be made via this binding post.
Sampler
Keyboard, Workstation
Output
Input
Return
Output 1 & 2
Send
Mic/Line Input
Output 3 & 4
Select the right mains voltage here: 230V or 115V.
Feed in the power of electrical life for your EQ MAGIX here. Only use the mains cable supplied.
12
Input
Mic / Line
Line -30 B
The INPUT stage of the EQ MAGIX is based on the SSM 2017 semicon­ductor. The strengths of this particular component are its extremely low noise and distortion characteristics. Unlike discretely designed circuits, the SSM 2017 has 64 transistor functions (discretely up to 24), thus achieving a common mode rejection of over 90 dB (measured at I
NSERT SEND).
Preamplification of the input signal is determined by the M
IC/LINE
control. The control range of the preamplification values ranges from +7dB to +65 dB. The maximum amplification value specified is a minimum value. The preamplifier stage provides up to +75 dB. This value can be lower, depending on the tolerance of the potentiometer, but it never falls below a value of +65 dB.
When setting the M
IC/LINE value, take note of the transducer type
(condensor or dynamic microphone) and the free-field transmission factor of the microphone type. The sound pressure level of the sound source to be recorded, the distance to the microphone and the room acoustics are other factors which also have to be taken into account when setting the M
IC/LINE
potentiometer. The free-field transmission factor of a dynamic microphone is around 2mV/Pa, that of a condensor microphone can be up to 20mV/Pa, which equals an increase in the output level of 20 dB.
The EQ MAGIX can also be used as a gain-on amplifier for Line signals. The input sensitivity of the preamplifier stage is reduced by 30 dB by pres­sing the L
INE -30 dB switch. The corrected preamplification value on the
M
IC/LINE control can be ascertained by subtracting 30 dB from the value set
on the potentiometer.
Alternatively, line signals can also be looped in via I
NSERT RETURN.
However, in this case, it is not possible to match the level, (see I
NSERT - page
14).
2
1
1
5
6
3
2
p
Control
elements
4
13
Peak
3
Phase reverse
4
The INPUT section of the EQ MAGIX is equipped with a PEAK LED which lights up approximately 3 dB below the value which would signify poten­tial overdriving of the output (I
NSERT SEND). The headroom of the INPUT
stage is around 26.5 dB.
The P
EAK LED does not indicate the overdriving limit of the PARAMETRIC
stage, as this varies, depending on the values set on the EQ. The PARAMETRIC stage has a lower headroom limit (+22 dB) when the stage is activated and the B
OOST/CUT control is on 0dB. If the PEAK LED lights up, and the
P
ARAMETRIC stage is in use, the preamplification (MIC/LINE) must be
decreased.
Pressing the phase switch (P
HASE REVERSE) inverts the polarity of the
microphone signal. When the switch has not been pressed (status LED is off), the polarity is »in phase«. Pressing the switch means that the polarity is »out of phase«.
Phase inversion can be used for a number of different reasons:
1. If, for example, the microphone signal of a singer or speaker is pream­plified in the EQ MAGIX and the monitor signal is folded back to the head­phones, the singer or speaker cannot hear himself very well. Pressing the phase switch inverts the polarity of the microphone and consequently, of the headphone signal, and the singer or speaker can then hear himself on his headphones without having to increase the level.
2. The phase inversion feature is also very useful when the polarity of the XLR input jack has to be inverted to match the polarity of the micro­phone or the microphone cable. The pin assigment of the XLR connector is as follows: Pin 2 = hot (+) and Pin 3 = cold (-).
3. Sometimes it is desirable to swop the polarity of a microphone
because of the sound.
Condensor microphones require a supply voltage of 48V DC which
supplies the microphone via the balanced audio lines (pins 2 and 3).
When the supply voltage is switched on, a phantom circuit is formed whereby the 48V DC supply voltage is applied simultaneously to the two supply lines (+/-) of the microphone and fed back via the cable screen.
There is no DC voltage between the two modulation lines which is why dynamic microphones can be used when the phantom voltage is switched on, without this doing the microphones any harm.
The influences of noise voltages which can superpose the DC supply voltage such as hum loops and parasitic currents in the cable screen are reduced by the phantom power supply. Moreover, this type of connection is particularly resistant towards RF.
As there is no potential difference between the +/- supply lines, the connection technique of the phantom supply is compatible with moving coil and ribbon microphones.
48 V
5
Phantom power supply according to
DIN 45 596 / IEC 268-15
Input
14
Insert
Input
All microphones with balanced floating output, i.e. also microphones equipped with tubes can be used when the phantom voltage is switched on.
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ooff mmiiccrroopphhoonneess aarree uusseedd..
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tthhee pphhaannttoomm ssuuppppllyy iiss sswwiittcchheedd OOFFFF..
There is a switchable INSERT path between the INPUT stage and the
P
ARAMETRIC stage. The signal can be fed to other sound processing units such
as compressors, limiters, de-essers or reverb units.
The I
NSERT jacks at the rear of the EQ MAGIX are designed as unba-
lanced jacks for S
END and RETURN.
It is also possible to use the microphone preamplifier independently of
the P
ARAMETRIC and VITALIZER stages via the INSERT, by feeding the micro-
phone signal out at the I
NSERT SEND jack, whilst feeding a second signal into
I
NSERT RETURN. This means that two independent signals can be processed
in the EQ MAGIX at the same time.
If there is no signal connected at the I
NSERT
jacks and the I
NSERT
switch is activated, the microphone signal is maintained, as the signal flow is not interrupted until there is a jack plugged into the S
END
and R
ETURN
jacks.
N
6
15
The ACTIVE function switches the PARAMETRIC equalizer on or off. If the
switch has been pressed, the integrated LED indicates that the P
ARAMETRIC
section has been activated.
The A
CTIVE funciton is a so-called "electronic bypass". Any DC voltages
are filtered out via coupling capacitors. To increase the operational safety of the monitor loudspeakers, you should, however, avoid switching the parameters on or off at a loud monitor volume levels. At high amplitudes inside the filter, there may be residual charges on the switching contacts which may be discharged when you switch over. These may become appa­rent as audible click sounds. If applicable, mute the monitor loudspeakers before switching a filter on or off. The M
UTE function of the OUTPUT stage of
the EQ MAGIX can be utilized for this purpose (see page 27, point 25).
The F
REQUENCY control determines the centre frequency of the frequency
band which is to be processed. The outer scaling ring indicates the selec­table frequencies when the frequency switch is not pressed. The frequency bandwidth ranges from 280 Hz to 58 kHz.
Equalizers do not normally provide frequencies above 20 kHz. Practical applications have shown, however, that interfere frequencies from digital audio equipment (quantization and formantization noise, crosstalk of the Sampling Rate etc.) can cause sound deterioration in the audible range. This particularly involves 44.1 kHz and 48 kHz and their related subhar­monics. The EQ MAGIX makes these frequencies accessible. They can be removed with the N
OTCH filter. (See point 12 on page 17 for more detailed
information on the N
OTCH filter). For the first time you have the opportunity
to intervene in these frequency ranges with a filter and to experiment your­self as to whether and the extent to which such crosstalks into the programme material can be corrected.
The frequency range of the F
REQUENCY control is divided by factor 20
after activating the switch (LED lights up). The control range of the F
REQUENCY control varies between 14 Hz to 3 kHz. This qualifies the EQ
MAGIX to carry out sound processing right down into the subsonic range.
With 14 Hz, the EQ MAGIX works below the range of human hearing. This means that the filter also features phase stability and accuracy at high amplitudes above 14 Hz.
Parametric
7
7
9
12
10
11
8
8
Active
Frequency
Practical applications bring accurate processing of subwoofer tracks to mind, along with a problem which modern recording procedures (PCM, hard disk, samplers etc.) frequently involve; here, the frequencies recorded are often in the infra-sonic frequency range (digital coding). When they are reproduced (which involves D/A conversion), low-frequency signal portions can cause phase distortions in the audible range, creating secondary effects which cannot be corrected subsequently. The EQ MAGIX can filter these interferences out.
On the other hand, modern sound reproduction technology is extending the range of frequencies which can be used sensibly, by the addition of lower and lower frequencies.
On the potentiometer scale, the frequency 1 kHz has been outlined for reasons of clarity and ease of orientation.
The diagram below shows the frequency range which can be processed by the EQ MAGIX in the P
ARAMETRIC stage: 14 HZ to 58 kHZ:
The B
OOST/CUT control determines amplification and attenuation of the
selected frequency range. Increases and decreases of +15 dB and -15dB are possible.
Apart from determining boost and cut, the B
OOST/CUT control has a
second function when the N
OTCH mode has been activated:
Once the N
OTCH filter has been activated, the BOOST/CUT control changes
to the R
OLL-OFF function, thus becoming the control for basic sound charac-
teristics (also see point 12, N
OTCH /ROLL-OFF). In the -15dB setting (extreme
left) the slope of the Notch (R
OLL-OFF) corresponds to a flat rise or fall. This
position is known as G
ENTLE. In the +15 dB setting, (extreme right), the
R
OLL-OFF corresponds to a steep rise or fall. This position is known as STEEP.
The EQ MAGIX is designed to be able to process individual signals and therefore supports the constant-Q principle so as to allow quick and accu­rate work, which also permits influencing the sound quite drastically.
In the constant-Q principle, the amplitude of any frequency selected
remains constant if the bandwidth (Q) is increased or decreased.
16
Parametric
9
Boost/Cut
Fig. 2:
The processable frequencies of the EQ MAGIX´s P
ARAMETRIC
stage
ranges from 14 Hz to 58 kHz.
As an example the frequencies 14 Hz, 280 Hz, 2 kHz and 58 kHz are boosted by +15dB.
17
Parametric
When the Q potentiometer is turned to the extreme left, the bandwidth around the selected centre frequency is very narrow. This is known as »high Q« with a value of Q3.6. When it is turned to the extreme right, the selected bandwidth is of maximum width, i.e. »low Q«. The value is Q0.6. The bandwidth factor is calculated from the width of the frequency curve on the -3 dB points relative to the 0 dB line.
The below diagram shows various Q values at a centre frequency of 1 kHz:
The Q-F
INE switch is responsible for fine tuning of the control characteri-
stics of the Q potentiometer. When the switch is activated, the Q values change in so that position Q3.6 (extreme left) takes on the value Q1.9. In the 12 o'clock position (Q1), all Q values are halved. The values between Q1 and Q0.6 remain unchanged.
Q-F
INE enables you to make more differentiated settings in the critical
control ranges of bandwidths relevant for musical applications. Two Q values can therefore be compared more easily by switching over quickly.
The N
OTCH filter is used to filter out discrete interference frequencies
where the maximum C
UT setting (-15 dB) on the BOOST/CUT control is not
sufficient.
The N
OTCH filter of the EQ MAGIX is variable in bandwidth (Q) and there-
fore, if it is used with broader bandwidths (low Q), it can also be used to filter out wide areas in the audio spectrum (e.g. lowering mids).
The F
REQUENCY control is responsible for a frequency range of between
14 Hz and 58 kHz (also see point 8 F
REQUENCY, page 15), thus enabling
removal of interference noise such as quantization and formantization noise which can be induced by digital equipment.
The N
OTCH filter's slope characteristics (known as ROLL-OFF) can be
varied. After N
OTCH mode has been activated, the BOOST/CUT control takes
on the function of the R
OLL-OFF control. This means that the slope characte-
Q
Q-Fine
Notch
10
11
12
Fig. 3:
5 different Q values with boost and cut at +/-15dB at 1kHz centre frequency.
18
ristics can be altered from GENTLE to STEEP, (also see point 9: BOOST/CUT , page 16).
IImmppoorrttaanntt::
If you switch on the N
OTCH mode, the bandwidth control Q
must be set at 0.6 (extreme right), so as to ensure a 1:1 level ratio with the original signal.
Narrower notches can be obtained if the Q control is turned to the extreme left. However, then the output level is also reduced by around 20dB.
Figure 4 shows the curves for the N
OTCH with GENTLE and STEEP characte-
ristics at Q0.6, along with the same curves at Q3.6.
Parametric
Fig. 4:
The N
OTCH
curves on the 0dB line are shown for Q0.6. On the outside, the curve is shown for G
ENTLEROLL-OFF
. The inside shows
the curve with S
TEEPROLL-OFF
.
The N
OTCH
curves on the -20dB line are shown for Q3.6. On the outside, the curve is shown for G
ENTLEROLL-OFF
. The inside shows
the curve withS
TEEPROLL-OFF
.
Fig. 5:
Three NOTCH curves with S
TEEP
R
OLL-OFF
. Placed at around 1 kHz,
44 kHz and 48 kHz.
19
Deleting an
interference
frequency
Two possibilities are available with the EQ MAGIX to delete a interfe-
rence frequency:
1. The C
UT mode with max. attenuation of 15 dB
2. The N
OTCH mode with max. attenuation of 30 to 50 dB.
In order to localize and delete an interference frequency proceed as follows:
1.a) Activate the P
ARAMETRIC stage.
1.b) Set the Q control to the smallest bandwidth (extreme left, Q 3.6)
1.c) Set the B
OOST/CUT control to max. BOOST (extreme right,+15 dB).
This helps to localize the interference frequency very quickly.
1.d) Sweep the F
REQUENCY control and stop if the interference
frequency has reached its loudest level.
1.e) Turn the B
OOST/CUT control to max. CUT (extreme left,
-15 dB). For broader interference noise the result is better if the Q value is shifted from its maximum position (extreme left) to lower Q values.
If 15 dB attenuation is not sufficient to eliminate the interference frequency satisfactorily, use the N
OTCH mode which offers an attenuation
down to -50dB:
2.a) Activate the P
ARAMETRIC stage.
2.b) Set the Q control to the broadest bandwidth (extreme right, Q=0.6)
2.c) Activate the N
OTCH mode.
2.d) Set the B
OOST/CUT control (i.e. ROLL-OFF control in NOTCH mode) to
S
TEEP (extreme right). This attenuates the noise frequency by 30
dB.
2.e) If this is not sufficient again, turn the R
OLL-OFF control to GENTLE
(extreme left). The attenuation is now 50 dB.
20
The initial settings on the V
ITALIZER
Switching on the V
ITALIZER
section
1.The P
ROCESS
control
2. The B
ASS
control
3. The MID-HIT
UNE
control
Introduction into
the VITALIZER
®
If you are working with a VITALIZER filter network for the very first time, it is advisable to operate the control parameters in a certain order to achieve optimum results as quickly as possible. You should use a mono signal of good quality as a signal source. You can either preamplify it in the I
NPUT
section or feed it directly into the INSERT RETURN, so that the signal goes directly into the P
ARAMETRIC section.
The picture above shows the initial settings on the EQ MAGIX. First, turn
the B
ASS control to the centre position (»0«); the HARMONICS and the
P
ROCESS control on zero as well (extreme left) and turn the MID-HI TUNE
control to 3.5 kHz. The -10 dB, DEEP and COMBINE functions are left on Bypass for the time being.
Press the A
CTIVE switch. There is no audible change in the sound at this
stage.
Slowly move the P
ROCESS control in from the extreme left. You will find
that there is no audible change in the sound until the
MIN position (ca. 11
o'clock). That is just how it should be. All frequencies from 3.5 kHz (initial setting M
ID-HI TUNE) are only raised with increasing intensity above this
point. First set the P
ROCESS control at 3 o'clock. The bass range is not yet
influenced at this point.
The next step is to shift the B
ASS control from the zero position to both
sides. Watch out for the differing bass sounds nuances, the creation of which is only controlled in that way by the V
ITALIZER.
Turn to the right: The bass sounds tight and dry. Turn to the left: The bass sounds soft and round.
You should perform these hearing tests on appropriate »full-range« monitors because near-field monitors normally cannot reproduce the deep bass generated by the V
ITALIZER in its entirety. Decide on a bass sound of the
desired amplitude.
Now start varying M
ID-HI TUNE. The original setting is 3.5 kHz. Turn to
the right: The programme material sounds brighter and gets more mids from about 1.5 kHz. The impression you hear is the reverse of the poten-
21
tiometer scaling: the lower the frequency, the brighter and clearer sounds the programme material. This is because the M
ID-HI TUNE control sets a
starting frequency above which all frequencies are processed. If this star­ting frequency is lowered, the frequency spectrum included in processing increases. The programme material then sounds brighter and clearer.
Turning the control to the left shifts the starting frequency from 3.5 kHz to higher frequencies. The programme material then sounds increasingly dull, because fewer and fewer frequencies are being included in the process, the higher the frequencies become. The setting you choose is a matter of personal taste.
A section within the V
ITALIZER with one of the most decisive influences on
the sound is P
ROCESS control. If you continue to turn the PROCESS control up,
more of the signal is added to the B
ASS and MID-HI TUNE sections whilst
dominant mid frequencies are reduced according human hearing at the same time. The below sections contain more detailed information on this aspect. Familiarize yourself with the sound changes before deciding on the setting which sounds best.
We shall now turn our attention to the H
ARMONICS control. Note the
improved detail in the high frequency range, the further you turn the control in. In practice, values between 4 and 6 have proved to be the most common.
The harmonics are accentuated by the V
ITALIZER with equalizer techno-
logy, unlike other procedures. Previously, so-called »Exciters«, devices to generate harmonic tones, produced their harmonics with the aid of a gene­rator which mainly added type K3 and type K5 distortions to the signal (odd harmonics of 3rd and 5th order). The familiar disadvantages of this principle are as follows: although odd harmonics do add to the brilliance of the audio signal to a significant degree, they tend to be somewhat sharp, which leeds to hearing fatigue for listeners. Another pitfall is that the distor­tions added were not part of the original signal.
The V
ITALIZER accentuates the harmonics which are also part of the
original signal! The H
ARMONICS filters are designed in such a way that even
and odd harmonics (K2, K3, K4, K5...) are accentuated equally. This makes the processed signal more natural with a soft, silky-sounding top-end. Once you have selected the setting for the harmonics control you can sit back to listen to the new sound image.
Switch A
CTIVE off to return to the original signal. If you now say »I don't
believe that« or »Booh«, you belong to the overwhelming majority of those people who have ever heard a V
ITALIZER. It was this sound impression
which led to V
ITALIZER technology winning awards like the »Golden Ear«
from Europe's biggest »Audio« magazine for the most innovative product in 1993.
4. The P
ROCESS
control It defines the process ratio between the B
ASS
and MID-H
I
T
UNE
section and the dry signal.
5. The H
ARMONICS
control
Introduction into the VITALIZER
®
22
The VITALIZER's
control elements
Active
Peak
+10 B
p
The ACTIVE function switches the VITALIZER section of the EQ MAGIX on or
off. The status LED indicates that the V
ITALIZER has been activated.
As with the P
ARAMETRIC stage, the ACTIVE function of the VITALIZER stage is
an »electronic bypass«. Any DC voltages are filtered out via coupling capa­citors.
To increase the operational safety of the monitor loudspeakers you
should not switch the V
ITALIZER on or off at high monitor volume. At high
amplitudes inside the filter, there may be residual charges on the switching contacts which may be discharged when you switch over. These may become apparent as audible click sounds. If applicable, mute the monitor loudspeakers before switching a filter on or off. The M
UTE function of the
O
UTPUT stage of the EQ MAGIX can be utilized for this purpose (see page
27, point 25).
The output signal of the P
ARAMETRIC stage is increased by 10 dB in the
sone scale (loudness scale) when the +10dB switch is activated. Increasing the drive level intensifies the V
ITALIZER 's working process.
This feature is especially suitable to liven up dull sounding samples but it
also proves useful when it comes to more effective voice processing.
The I
NPUT stage of the VITALIZER section is equipped with a PEAK LED
which lights up around 3 dB before the V
ITALIZER effect signal path is poten-
tially overdriven. Make sure that the P
EAK LED only lights up briefly, if at all.
It is essential to avoid the P
EAK LED being lit up for any length of time.
There are four possible ways to prevent Clipping:
Firstly: if the +10dB feature is switched on, switch it off. Secondly: reduce the gain in the P
ARAMETRIC section.
Thirdly: Reduce the microphone or line preamplification. Fourthly: Reduce the output volume of a looped-in device (I
NSERT).
20
21
19
18
13
16
14
15
17
13
14
15
23
The BASS control is responsible for the »colour« of the bass sound your
signal is to have. If you move the B
ASS control to the right, you get a drier,
percussive bass sound, known as T
IGHT. As a result of this, on the right-
hand side of the scaling points, there are squares which increase in size, in line with increased intensity. They symbolize the contoured »T
IGHT« bass
sound.
If the B
ASS control is moved from the centre position (0) to the left, the
bass sound becomes very deep, soft and warm. This sound is known as S
OFT. This is symbolized with round scaling points which also increase in
size as the intensity increases.
The further the B
ASS control is shifted to the right or left of the centre
position, the more intensive the bass sound in question. However, P
ROCESS
must be positioned to the right of the MIN setting for the bass to be audible.
You can always hear the original (dry) bass if the B
ASS control is in a
centre position.
The P
ROCESS control determines the processing ratio between the set
bass sound colour and the original signal. This results in varying bass sound structures: if you combine high bass amplification on the B
ASS control with
a lower P
ROCESS value, you get a different bass structure than with a lower
bass amplification combined with a higher P
ROCESS value. Choosing the
best solution is a matter of personal taste and also depends on the type of original signal involved.
Bass
16
The VITALIZER's control elements
Fig. 6:
The dotted line shows frequency responses for a soft Bass (S
OFT
)at
maximumP
ROCESS
and a MID-H
I
T
UNE
of 3.5 kHz.
The solid line shows the phase response, which always drifts only a few degrees if the amplitude is increased.
Fig. 7:
The dotted line shows frequency responses for a hard Bass(T
IGHT
)
at maximum P
ROCESS
and a MID-
HIT
UNE
of 3.5 kHz.
The solid line shows the phase response whichhas a phase rela­tion of -180° at 50 Hz, but other­wise also drifts only by a few degrees at increasing amplitudes.
24
Deep
Mid-Hi Tune
17
18
The DEEP circuit increases the processed bass range. The bass range encloses frequencies between ca. 20 Hz and 110 Hz with a bass centre frequency at 50 Hz. The D
EEP function enlarges this range to approx. 16 Hz
to 140 Hz with the same bass centre frequency and increases the amplifi­cation level by ca. 3 dB.
The M
ID-HI TUNE control is used to set the starting frequency of the
broad-band shelving filter. In line with the setting of P
ROCESS control, all
frequencies above this value right through to the end of the audio range are processed.
The control range of the M
ID-HI TUNE control is between 1 kHz (extreme
right) and 20 kHz (extreme left). In practice, common settings vary between 3.5 kHz and 8 kHz.
As the human ear perceives the range between 1 kHz and 3 kHz parti­cularly clearly, at all volumes between 0 and 120 phon it makes sense to adapt this frequency range. You might feel inclined to say "Yes, but I do that with my graphic EQ as well". The main difference is that the graphic EQ really reduces the effective loudness of the frequency, i.e. cuts out the appropriate frequencies, thus changing the spectral content of the original signal. The V
ITALIZER , however, relies on a more subtle method of ampli-
tude-depending phase shifting. This does not involve altering the spectral composition of the signal but it does maintain the subjective impression of loudness. Moreover, graphic equalizers produce comb-filter effects because of the interaction between adjacent filters, when broad-band frequencies are raised. The M
ID-HI TUNE filter can raise the broad-band spectrum with a
very linear frequency response, without colouring the signal.
Above the M
ID-HI TUNE value set, the VITALIZER filters create a linear
increase, i.e. one that is adapted to the human ear. This compensates any inability of our hearing as regards perceiving frequencies ranging between 5 kHz and 10 kHz. The M
ID-HI TUNE filter works with a wide bandwidth
and always sounds musical, never „bell-like“. Gradually go down from 20 kHz (extreme left) to lower frequencies. The further down you go, the brighter the sound image becomes, as an increasing number of frequencies are included in the process.
The M
ID-HI TUNE control can also be used to tone down excessively
sharp-sounding material, by setting frequencies of 10 kHz or higher, and setting the P
ROCESS control on MAX. Seeing as the PROCESS control is also
responsible for deleting dominant mid frequencies, all frequencies are gradually reduced down to the application frequency, in conjunction with high starting frequencies of the M
ID-HI TUNE control.
The VITALIZER's control elements
25
Fig. 8:
Five frequency responses are shown for the MID-HIT
UNE
filter at
max. P
ROCESS
value and
B
ASS
at 0.
1. 1 kHz
2. 2 kHz
3. 3,5 kHz
4. 8 kHz
5. 20 kHz
Fig. 9: The dotted line shows frequency responses for a soft Bass (S
OFT
)at
varying P
ROCESS
and a MID-HIT
UNE
of 3.5 kHz.
The solid line shows the phase responses, which always drift only a few degrees if the P
ROCESS
inten­sity is increased. The diagram shows very clearly that the mid attenuation gets stronger as the P
ROCESS
value
increases.
The VITALIZER's control elements
The third control of the VITALIZER section determines the ratio between
B
ASS and MID-HI TUNE to the original signal. The HARMONICS control is not
affected by the P
ROCESS control.
The P
ROCESS control determines the damping intensity of dominant mid
frequencies. This allows rapid adaptation to the loudness curves (Fletcher­Munson curves, curves of equal loudness).
The human ear perceives the audio frequency spectrum at varying sound pressure levels very differently. Perception is by no means »linear«. The V
ITALIZER alters the frequency spectrum in such a way that the balance is
maintained between all frequency ranges even at varying monitor volumes. For the human ear, the sound is more pleasant and easier to perceive than the original. In other words, increasing the P
ROCESS value also
increases the intensity of the M
ID-HI TUNE filter and the BASS filter, whilst
dominant mid frequencies are damped by amplitude-controlled phase shiftings. This improves the perception of loudness, clarity and the bass punch, i.e. the strength and fullness of the audio signal.
19
Process
1
2 3 4
5
26
Combine
21
The VITALIZER works with steep filters and controlled changes of the phase
relationships of the harmonics to process the harmonics structure.
We consciously did without the generator principle of »Exciters«. The
V
ITALIZER's harmonic filter does not add any distortions to the original
signal, unlike with the generator principle. It extracts all the information it needs from the original signal. This significantly reduces the hearing fatigue effect on the listener. By influencing the phase relationship in an intelligent fashion, the harmonics which have been filtered out are empha­sized with increasing addition expressed as a percentage. The effect signifi­cantly improves the speech intelligibility and the transparency. Old archived recordings sound fresh and silky again. The brilliance of any audio signal can be improved without it sounding sharp.
The H
ARMONICS filter derives its input signal from the original signal and
the output of the M
ID-HI TUNE filter. If you close the PROCESS control
(extreme left), the B
ASS and MID-HI TUNE controls do not function any more.
You can then listen to the H
ARMONICS control separately.
The second potentiometer level of the M
ID-HI TUNE control is responsible
for the cut-off frequency of the H
ARMONICS filter. A variation of the MID-HI
TUNE control alters the cut-off frequency (fundamental tone) of the harmo­nics. Both filters complement each other in an ideal fashion as they each always process the part of the audio signal which is not being processed by the other filter. If the M
ID-HI TUNE control is set at 20 kHz, the HARMONICS
filter intervenes at low frequencies. If the MID-HI TUNE filter is at 1 kHz, the H
ARMONICS filter affects higher frequencies. The characteristics of the two
filters therefore complement each other in an ideal fashion.
The C
OMBINE circuit is used to combine the PARAMETRIC and the VITALIZER
sections.
The V
ITALIZER needs the original signal portion to define the mid attenua-
tion by the P
ROCESS. If the mid attenuation is not required, COMBINE switches
the original signal off.
The P
ROCESS control becomes the LEVEL control of the VITALIZER. Normally,
the L
EVEL control is set at MAX.
When C
OMBINE has been activated, the VITALIZER works like an equalizer
which works on a purely additive basis.
Harmonics
20
The VITALIZER's control elements
27
Output
The OUTPUT section is an output stage with active PAN control. A double Mono signal is produced from the Mono input signal which is available via the balanced and unbalanced outputs. The output signals can be fed to two insert returns on the mixing desk, a recorder or a stereo effects processor.
The active P
AN control determines the balance between the left and right
output channel. Unlike the passive pan-pot on cheaper mixing desks, the EQ MAGIX active P
AN control is able to compensate for losses in loudness
of up to around 3 dB. P
AN control also proves useful if output signals are
being looped into insert points on the mixing desk where the user wants to split the Mono signal actively into two Mono signals for further processing on the mixing desk, which should have different levels on the insert return.
The output peak levels (PPM values) are indicated on the LED display. The levels are indicated in steps of 3 dB from -18 dB to + 9 dB.
The F
ADER switch converts the PAN control to a FADER function. The level is
not altered when the potentiometer is set in the centre position. A attenua­tion of around -50 dB is possible on both sides of the control setting.
This function is useful to compensate an increase in level compared with the input signal, which may have been caused due to processing in the P
ARAMETRIC and VITALIZER sections. On the other hand, a variable output is
also useful to prevent overdriving units located downstream.
The M
UTE function switches the EQ MAGIX outputs off. Similar to the
M
UTE functions of a mixing desk channel, muting can be performed when
recording a signal directly from EQ MAGIX on to a R-Dat or the like after the recording has taken place, without the level settings having to be changed.
23
23
22
22
25
25
24
24
Pa n
Mute
Fader
PPM Meter
28
EQ MAGIX
Specifications
FFrreeqquueennccyy rraannggee
10 Hz - 100 kHz (100 kHz = -3dB)
EEqquuaalliizzeerr FFrreeqquueennccyy rraannggee
14 Hz - 58 kHz
CCMMRRRR
(common mode rejection ratio) -85dBu @ 100 Hz
(Set-up for measurements: input resistor 150 Ω,
-76dBu @ 1 kHz
0dB, measured at the XLR output)
-65dBu @ 15 kHz
TTHHDD && NN
(total harmonic distortion & noise)
(Set-up for measurements: input resistor 150 Ω, 0dB, measured at the XLR output)
SSiiggnnaall ttoo NNooiissee
AA--WWTTGG CCCCIIRR 446688
IInnppuutt ssttaaggee
XXLLRR
(MIC/LINE): Instrumentation amplifier, electronically balanced (differential) transformerless nominal input level +6dB
JJaacckk
(INSERT RETURN): unbalanced nominal input level 0dB
Input impedance (XLR, balanced) < 100 k Input impedance (INSERT RETURN, unbal.) < 47 k
OOuuttppuutt ssttaaggee
XXLLRR
: electronically balanced (differential) transformerless nominal output level +6dB
JJaacckk
(INSERT SEND/OUTPUTS): unbalanced nominal output level 0dB
Output impedance (XLR, balanced) = 75 Output impedance (jack, unbal.) < 600 Output impedance (INSERT SEND, unbal.) < 600
PPeeaakk iinnddiiccaattoorrss
Output peak (preamp): LED lights up 3dB before clipping Input peak (VITALIZER): LED lights up 3dB before clipping
CChhaassssiiss
RF-proof aluminium housing
DDiimmeennssiioonnss
19"/1U; 482 x 44 x 237mm
WWeeiigghhtt
2,7kg
Gen.: 0dBu +20dBu 0dBu Preamp: min min +60dBu
20 Hz 0.0132 0.0025 0.1080 % 1 kHz 0.0131 0.0028 0.0612 %
10 kHz 0.0161 0.0164 0.0590 % 20 kHz 0.0202 0.0281 0.0590 %
All PQ PQ + Vita. All Bypass in in Max
92,74 89,91 89,67 79,85dB 87,60 81,72 81,72 72,34dB
29
SPL electronics GmbH (hereafter called SPL) products are warranted only in the country where purchased, through the authorized SPL distributor in that country, against defects in material or workmanship. The specific period of this limited warranty shall be that which is described to the original retail purchaser by the authorized SPL dealer or distributor at the time of purchase.
SPL does not, however, warrant its products against any and all defects:
1) arising out of materials or workmanship not provided or furnished by SPL, or
2) resulting from abnormal use of the product or use in violation of instructions, or
3) in products repaired or serviced by other than authorized SPL repair facilities, or
4) in products with removed or defaced serial numbers, or 5) in components or parts or products expressly warranted by another manufacturer.
SPL agrees, through the applicable authorized distributor, to repair or replace defects covered by this limited warranty with parts or products of original or improved design, at its option in each respect, if the defective product is shipped prior to the end of the warranty period to the designated authorized SPL warranty repair facility in the country where purchased, or to the SPL factory in Germany, in the original packaging or a replacement supplied by SPL, with all transportation costs and full insurance paid each way by the purchaser or owner.
All remedies and the measure of damages are limited to the above services. It is possible that economic loss or injury to person or property may result from the failure of the product; however, even if SPL has been advised of this possibility, this limited warranty does not cover any such consequential or incidental damages. Some states or countries do not allow the limitations or exclusion of incidental or consequential damages, so the above limitation may not apply to you.
Any and all warranties, express or implied, arising by law, course of dealing, course of performance, usage of trade, or otherwise, including but not limited to implied warranties of merchantability and fitness for particular, are limited to a period of 1 (one) year from either the date of manufacture. Some states or coun­tries do not allow limitations on how long an implied warranty lasts, so the above limitations may not apply to you.
This limited warranty gives you specific legal rights, and you may also have other rights which vary from state to state, country to country.
SPL electronics GmbH
41372 Niederkrüchten, Germany
Warranty
SOUND PERFORMANCE LABORATORY
SPL electronics GmbH, Tel. +49-(0) 21 63 / 98 34-0, Fax +49-(0) 21 63 / 98 34-20
Factory address: Sohlweg 55; D-41372 Niederkrüchten
Postal address: P.O. Box 12 27; D-41368 Niederkrüchten
1994 All rights reserved, printed in Germany
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