Studiomaster Powerhouse 300 User manual

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INTRODUCTION
1:1 General introduction to POWERHOUSE consoles 2
1:2 IMPORTANT AC Power Information 2
1:3 IMPORTANT Cooling Information 3
1:4 IMPORTANT To Protect-Your Loudspeakers 3
CONTROL IDENTIFICATION
2:1 The input channel 4
2:2 The output section 5
2:3 The rear panel 8
USING THE POWERHOUSE
3:1 First things first 9
3:2 The input channel connectors 9
3:3 How to get the input sound through to the headphones 9
3:4 The equalisation section on the input channels 10
3:5 REV, AUX and MON 10
3:6 The graphic equalisers 12
3:7 Tape record and playback sockets 12
3:8 Phantom powering 12
3:9 The SEND/RET jacks 13
REVERB
4:1 Digital Reverberation 14
4:2 The controls 14
4:3 Technical data 15
4:4 In Use 15
4:5 Specifications 16
SPECIFICATIONS
5:1 Mixing console specifications 17
5:2 Amplifier specifications 18
5:3 Graphic equaliser specifications 18
5:4 Dimensions and weights 18
GLOSSARY OF TERMS
6:1 Glossary of Terms . 19

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1:1 GENERAL INTRODUCTION TO POWERHOUSE CONSOLES
Please read this manual thoroughly from front to back and keep it close at hand during operation.
The Studiomaster POWERHOUSE consoles have, in one compact box, a comprehensive mixing console, built-
in 127 program Stereo Digital Reverb, dual graphic equalisers, and a 2x300W power amplifier.
It will come as no surprise that the POWERHOUSE is extremely versatile; it can be used as a complete P.A.
system for small bands, or as a self-contained sub-system in larger applications.
All of the features of the POWERHOUSE can be used in a variety of ways, for ultimate flexibility. This manual will
introduce you to the many and varied ways of using it.
DO NOT switch on the console before reading the following sections.
1:2 IMPORTANT! AC POWER INFORMATION
PLUG WIRING INFORMATION
As the colours of the wires in the AC Power Lead of this apparatus may npt correspond with the coloured markings
identifying the terminals in your plug, proceed as follows:
The GREEN & YELLOW wire must be connected to the terminal in the plug which is either:
marked by the letter "E"
or by the safety earth symbol " "
or coloured GREEN
or coloured GREEN & YELLOW.
The BLUE wire must be connected to the terminal which is marked with the letter "N", or coloured BLACK.
The BROWN wire must be connected to the terminal which is marked with ;the letter "L" or coloured RED.
WARNING: THIS APPARATUS MUST BE EARTHED
BEFORE PROCEEDING: DO NOT CONNECT THE AC SUPPLY LEAD TO THE CONSOLE
The following section relating to the power input assembly fitted to the rear panel of console MUST be read before
switching on.
The consoles are fitted with this voltage selector/AC input/AC fuse assembly: pointer
(indicates voltage selected)

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The voltage selector (the square shaped part which can be levered out) contains the AC fuse.
This is the voltage selection procedure. Check that the pointer (see diagram above) is pointing at the local AC
supply voltage (100, 120, 220 and 240V are stamped on the voltage selector). If it is, then go ahead and connect AC
power to the console.
If the voltage indicated is wrong, then lever out the voltage selector (there is a small notch for this purpose between
the selector and the AC power input). Turn the selector round until the pointer is pointing to the correct voltage, then
press it back in.
You will have noticed a fuse while the selector was out. This is the console's AC fuse. It is a 20x5mm T2A 250V in
all units. The console is now ready to have the power lead connected and be switched on.
1:3 IMPORTANT! COOLING INFORMATION
There is a cooling vent in the base of the POWERHOUSE consoles. This MUST NOT be obstructed in any
circumstance, as overheating of the unit will occur.
If the POWERHOUSE is transported in a flightcase, it should be lifted completely from the flightcase before use.
1:4 IMPORTANT! TO PROTECT YOUR LOUDSPEAKERS
Always turn the TO AMP control to 0 before turning the console on or off.

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2:1 INPUT CHANNEL
NOTE: Use either the MIC or LINE input and NOT both together as this could
damage the MIC input circuitry or the equipment connected to it.
1 MIC INPUT Female XLR wired Pin 1 = Ground, Pin 2 = +ve phase. Pin 3 = -ve phase. The
channel may be driven with a low impedance balanced microphone. Input impedance
2kohm, gain range 15 to 60dB.
2 LINE INPUT Stereo 0.25" jack wired Tip = +ve phase, Ring = -ve phase, sleeve = ground. For
unbalanced use, connect a mono jack wired Tip = Signal, Sleeve = Ground.
3 GAIN control with 45dB range. Operates both LINE and MIC level inputs to ensure that
the input signal is at a suitable level to drive the channel. It determines the nominal
channel signal level by varying the pre-amp gain, preserving maximum headroom and
minimum noise without loading the input signal.
4 EQUALISATION A 3-band design comprising of:
4a High Frequency control is a shelving type with 16dB of boost/cut at 12kHz.
4b MID Frequency control is a peak/dip type with 16dB of boost/cut at 2kHz.
4c Low Frequency control is a shelving type with 16dB of boost/cut at 60Hz.
5 REV Turning this control clockwise sends the input channel signal to the 127 program
DIGITAL REVERB built in to the POWERHOUSE. The REV control is post-fade.
6 AUX This control is post-fade, like the REV control, but sends the input channel signal to
the AUX SEND jack. The AUX SEND would normally be connected to an effect.
7 MON The MON control is pre-fade, and turning it clockwise sends the input channel signal
to the MON SEND jack. The MON SEND would normally be connected to an amplifier
for foldback purposes.
8 PAN control allows a left-right stereo balance of the channel between the left and right
busses.
9 CLIP indicator. This LED illuminates whenever the signal approaches the maximum running
level. It monitors all stages within the input channel, and illuminates at 3dB prior to
clipping.
10 L-R/GRAPHIC button. When released, (L-R selected), the channel will be connected to the left and
right busses directly. To mix the input channel signal onto the left and right busses via
the GRAPHIC EQUALISER, depress this button.
11 FADER 60mm channel fader with 10dB of gain.

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2:2 OUTPUT SECTION
1 DIGITAL REVERB The POWERHOUSE consoles have a built in reverb with a total of 127 programs.
The various programs are clearly labelled, on the front panel, for rapid accessing of
the desired effect.
The reverb is stereo, and its outputs are connected to the left and right busses. The
ON/OFF button switches the DIGITAL REVERB on or off. When it is not required, it
should be switched off. Depress for ON, and the adjacent LED will light.
There are six reverb "types" (each of which can be DARK or BRIGHT and have any of
eight reverb times), three reverb effects (which can also have any of eight preset
reverb times) plus seven SPECIAL EFFECTS.
The reverb types are selected by the TYPE button. Each tiroe this button is
depressed, the lit LED above it "moves" down the row to indicate the type selected.
The bank SELECT button selects whether the reverb type is BRIGHT or DARK. The
DARK/BRIGHT selection is shown by the two LEDs adjacent to the BANK SELECT
button.
The TYPE and BANK SELECT buttons also select the three reverb effects and gain
access to the 7 SPECIAL EFFECTS (GATED, DELAY, REVERSE & SPECIAL) by
moving the LED down with the TYPE button, and using the BVMK SELECT button to
toggle between GATED and DELAY, or REVERSE and SPECIAL.
The eight different times available for each of the reverb types and effects are preset
and vary for each type/effect selected. The time is selected by using the
SPECIAL/TIME button in the same way as the TYPE button.
When SPECIAL has been selected, the SPECIAL/TIME button is used to select any
of the 7 SPECIAL EFFECTS. These have all their parameters pre-programmed to
create the effect.
The O/LOAD LED will light when the level of the mix of signals sent to the reverb
(controlled by the REVERB fader reaches a level 3dB below overload occurs to warn
of clipping distortion.
2 POWER ON This LED lights when AC power has been switched on at the rear panel of the
console.
3 LED METERS These display the LEFT & RIGHT OUTPUT levels. The meters are 12-segment, 2-
colour with typical VU meter ballistics.
4 GRAPHIC EQUALISER
The graphic equalisers are assigned to the left and right busses. They control the
equalisation of the mix of signals routed to them by the L-R/GRAPHIC buttons on
each of the input channels. If, when adjusting the graphic equaliser, the overall mix
level becomes too low or too high, the TRIM fader on each graphic equaliser can be
used to compensate for this. To remove the graphic equalisers from the signal path,
simply release all L-R/GRAPHIC buttons on input channels.
5 REV TO MON Depress this button to route the REVERB to the MON buss (normally used for
foldback).
6 MON FADER The MON controls on each of the input channels have their overall, mixed level
determined by the MON FADER. This fader controls the output level of the MON
SEND jack.
7 REVERB FADER The REV controls on each of the input channels have their overall, mixed level

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determined by the REVERB FADER. This fader controls the level INTO the reverb,
and when adjusting it, the O/LOAD LED should be checked to make sure that the too
high a signal level is not being fed to the reverb.
8 LEFT & RIGHT/MASTERS FADERS
These are dB calibrated for accurate signal level settings to be made. These control
the overall mix level on the left and right busses. The signals which can make up this
mix are input channels (with or without GRAPHIC EQUALISATION), the DIGITAL
REVERB, and the STEREO RETURN.
9 +48V When this switch is depressed, it applies +48V Phantom Power, to all MIC INPUT
XLR Pins 2 and 3, to power condenser microphones.
10 STEREO RETURN
0.25" mono jacks wired Sleeve = Ground, Tip = Signal. Input impedance 10kohm.
These are connected to the left and right busses. If a signal is connected to the LEFT
jack only, then it will be routed, as MONO, to both the left and right busses.
11 F/S 0.25" mono jack wired Sleeve = Ground, Tip = Signal. This jack socket is wired in
series with the REVERB ON/OFF button. When a footswitch is connected to it, it
allows the REVERB to be switched on or off remotely. The REVERB ON/OFF button
on the console must be released (OFF) for the footswitch to operate.
12 LEFT & RIGHT LINE OUT
0.25" mono jacks wired Sleeve = Ground, Tip = Signal. These are the main outputs
from the POWERHOUSE mixing console for connecting to an external amplifier/P.A
system. They allow a signal to leave the POWERHOUSE before the built-in power
amplifier, but they do not break the signal path. This allows a second amplifier system
to reinforce the output of the built-in amplifier, or drive speakers in another part of a
venue, the foyer perhaps.
The LINE OUTS are, however, most useful when the built-in amplifier is being used to
drive the on-stage monitor system; MON selected by the AMP L-R/MON button. The
LINE OUTS would then drive the Front-of-House amplifier/P.A. system.
13 MON SEND 0.25" mono jack wired Sleeve = Ground, Tip = Signal.
14 AUX SEND 0.25" mono jack wired Sleeve = Ground, Tip = Signal.
15 RECORD Phono sockets for connection to the inputs of a 2-track recorder. They are wired
parallel with the LINE OUTS and allow the stereo mix (from the left and right busses)
to be recorded conveniently during a performance. Nominal level -10dBV. Minimum
load 5kohm.
16 PLAYBACK Phono sockets for connection to the outputs of a 2-track recorder. When the
PLAYBACK button is depressed, they are routed to both the left and right busses
(remaining stereo) and also to the MON buss (as mono). Input impedance 5kohm.
17 LEVEL This controls the level of the stereo PLAYBACK signal onto the left and right busses.
18 TO MON This controls the level of the mono sum of the stereo PLAYBACK signal onto the
MON buss.

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19 AUX SEND This controls the overall output level at the AUX SEND jack, of the mix of signals
derived from the AUX controls on the input channels.
20 TO AMP This is the master volume control for the built-in stereo 2x300W power amplifier. The
LEFT & RIGHT FADERS, or the MON FADER (depending on the selection made on
the L-R/MON switch below) must be raised to allow this control to work.
21 L-R/MON This button is for selecting whether the left and right busses or the MON buss are
routed to the built-in amplifier.
22 L-R/MON This button is for selecting whether the left and right busses or the MON buss are
routed to the PHONES socket.
23 PHONES This is the output volume control for the headphones.
24 PHONES socket. For stereo headphones. 0.25" stereo jack wired Sleeve = Ground, Ring =
Right, Tip = Left. The headphone amplifier is designed to cater for headphones with a
minimum impedance of 400 ohms.
NOTE : The LED bargraphs are connected to the main (left/right) outputs of the mixer section
and are calibrated to indicate an output level of 0dBu (.775V) when the first red LED is
illuminated.
The amplifier section gives maximum output with an input signal of 0dBu (.775V), so
when the "To Amp" control is turned fully clockwise, red LEDS are accompanied
by distortion at the speaker outputs.
When the "To Amp" control is set below 10, there is no direct relationship between the
bargraphs and the amplifier output.

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2:3 THE REAR PANEL
1 AC POWER ON SWITCH.
2 AC POWER INPUT.
3 LEFT & RIGHT INSERTS. The position of these insert points in the signal path is just before
the power amplifiers. Their main purpose is for the patching in the pre-amp/crossovers which
are supplied with some compact speaker systems. Effects can also be connected here if
required.
4 OUTPUTS. These XLRs are the amplifier outputs and connect directly to loudspeakers (min
impedance 4ohms).
5 COOLING FAN. This vent MUST NOT be obstructed while the POWERHOUSE is in use.
NOTE : High voltages are present at the speaker outputs. Avoid touching exposed XLR pins and/or
jack plug tips.
Use only heavy duty speaker cables. Screened signal leads (guitar lead etc) are unsuitable
since they cannot safely withstand the high current.

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USING THE POWERHOUSE
3:1 FIRST THINGS FIRST
Set all console controls to their minimum, or zero position: all levels fully anticlockwise, pans to centre,
faders to oo. Make sure all switches are set OUT. Switch OFF +48V Phantom Power. Connect either
loudspeakers (min. impedance 4ohms) to the OUTPUTS, or stereo headphones (min. impedance 400ohms)
to the PHONES jack.
Switch on the console.
3:2 THE INPUT CHANNEL CONNECTORS
For each input channel there are two connectors: a female XLR labelled MIC and a standard 0.25" stereo
jack labelled LINE. The MIC socket is designed for low level signals, typically generated by microphones.
The LINE socket is for higher level (or "line level") signals produced by drum machines, keyboards, some
electric guitars, tape machines etc.
NOTE: Use only the MIC or LINE socket on an input channel, NEVER both together.
For the purpose of setting up the console, connect a keyboard or tape machine to the LINE input of a
channel so that a continuous signal is fed to the channel).
At this stage, a signal has entered the console but nothing can be heard.
3:3 HOW TO GET THE INPUT SOUND THROUGH TO THE HEADPHONES
1 The GAIN control. Adjust this control until it reads about 20 on its scale. The signal within the input
channel has its level determined by this control.
2 The CLIP indicator. Check that this LED is not lit. This LED will only light when the signal level within
the channel (pre- or post-fader) is too high. It illuminates just before "clipping" occurs, to warn that
the channel is near its limit. If a signal clips, then it will be distorting. If it does light, then take one of
the following steps:
a Reduce the GAIN control level until the light goes off.
B Reduce the output level of the input source (keyboard etc.).
3 The PAN control. All inputs are routed to the left and right busses (see L-R/GRAPHIC button below).
The PAN control determines how much of the signal goes to left or right. In the centre position, the
input signal level is equal on both left and right busses.
4 The L-R/GRAPHIC button. Depressing this button will send the input channel signal to the left and
right busses via the graphic equalisers. To bypass the graphic equalisers, leave the button released.
5 The input channel FADER. The output level of the channel is set by this control, and for the time
being, it is best set at 0dB on its scale. At this point, raising the channel fader presents the incoming
signal to the left and right busses and the level of this signal is now passed directly to the
LEFT/RIGHT faders.

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Raising these faders will show the signal level on the LEFT/RIGHT bargraphs and it can be heard in
the headphones (the headphones also have their own level control).
If loudspeakers are connected, then the TO AMP control should be turned clockwise, then the sound
will also go to the loudspeakers. DO NOT allow the signal to go beyond the first red LED on the
bargraph.
3:4 THE EQUALISATION SECTION ON THE INPUT CHANNELS
The function of equalisation is to increase or decrease selected frequencies to either achieve a particular
sound, or eliminate an unpleasant characteristic.
To set the EQ flat (no frequencies cut or boosted), set to zero (centre) the three knobs calibrated in dB. Turn
clockwise the HF (treble) control, then turn it back to zero and compare the sounds. Notice the difference?
What you have done is BOOST high, or treble, frequencies. The EQ network covers the whole range of
audible frequencies from treble to bass.
The electronic characteristics and frequencies of STUDIOMASTER EQ are unique and are developed to
SOUND good. The main purpose of EQ is to correct deficiencies in a sound source's frequency response,
but used creatively it can also enhance sounds. POWERHOUSE has an EQ network that when mastered
can make mediocre sounds good, and good sounds excellent. Practise is recommended.
3:5 REV, AUX & MON
The POWERHOUSE consoles have three controls on each input channel which can be used to send the
input channel signal to be processed, or used elsewhere; the REV, AUX and MON controls.
THE REV CONTROL
Turning this control clockwise sends the input channel signal to the built-in DIGITAL REVERB. By using
several REV controls on the input channels a mix is created at the REVERB FADER. The setting of this
fader controls the level of signal fed to the REVERB. When adjusting it, check that the REVERB O/LOAD
LED does not light.
THE AUX CONTROL
The AUX control is just like the REV control, but allows an external effect processor to be used. Adjusting
several AUX controls creates a signal mix at the AUX SEND control which sets the level of the output from
the AUX SEND jack. This would be connected to the input of an effect processor such as delay, enhancer,
compressor etc.
Like the REVERB FADER, the AUX SEND control alters the signal level fed IN to the effect, so check the
overload indicator of the external effect to avoid clipping or distortion.
REV & AUX, POST-FADE
The REV and AUX controls are "post-fade". Post-fade means that their level is affected by the position of
the channel fader. They are effects sends. The reason for this is that a mix is set, say from inputs 1 to 5,

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with "dry" input signals using the channel faders. Turning REV on each of the inputs 1 to 5 by the same
amount means that the same mix levels that were sent to the left and right busses by the channel faders are
now at the REVERB FADER. The AUX controls work in exactly the same way, but allow a different external
effect to be used.
MIXING EFFECTS
Both the REVERB and the effect connected to the AUX SEND need to be returned to the left and right
busses to be added to the mix.
The outputs of the built-in REVERB are connected directly to the left and right busses, so simply raise the
REVERB FADER to mix the "wet" (reverb added) signal to the rest of the mix. The REVERB FADER
actually controls the signal level being fed IN to the REVERB. This allows the REVERB to be removed from
the mix (with the fader setting preserved) by switching the REVERB OFF, either at the console, or via the
optional remote footswitch.
The outputs of an effect processor connected to the AUX SEND jack can be returned for mixing at either of
two places. The first is the STEREO RETURN, which is ideal for, perhaps, an autopanner or other effect
which operates in stereo. The STEREO RETURN jacks are connected directly to the left and right busses,
and the level of signal added to the mix is set by the AUX SEND control. For a mono effect, use only the
LEFT jack of the STEREO RETURN.
The other place the effect can be returned is a LINE input. The effect return would then be treated like any
other input signal and routed to the left and right busses, with the option of mixing it via the GRAPHIC
EQUALISERS (by depressing the L-R/GRAPHIC BUTTON). For a stereo effect, two LINE inputs will be
required. Using one or more LINE inputs for returning an effect should be considered very carefully, and
usually only when input channels are spare.
WARNING: DO NOT return the effect connected to the AUX SEND into an input channel and turn the AUX
control on that input channel - the console will start to oscillate.
THE MON CONTROL
While the REV and AUX controls are used for adding effects to the mix, the function of the MON controls is
to allow the performers to hear themselves playing. Adjusting MON controls on the input channels creates a
mix at the MON FADER, which sets the output level of the MON SEND. This would normally be connected
to an amplifier and monitor speaker, or headphone system, for the performers to listen to themselves.
MON, PRE-FADE
Pre-fade sends are used for foldbacks (on-stage monitoring) because a relative mix of signals different to
that used for front-of-house can be sent to the stage (performers generally do not want the same signal mix
as front-of-house). This is possible with the MON controls as they are pro-fade and therefore independent of
the input fader levels that have been set for the main mix.

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MORE ABOUT THE MON SYSTEM
The MON system on POWERHOUSE consoles has a number of useful additional features. The REVERB
can be routed directly to MON by depressing the REV TO MON button. If the built-in stereo 2x300W
amplifier is not being used for the main mix, then it can be used to power the foldback system if the L-
R/MON button below the TO AMP control is depressed. Also, MON can be sent to the operators
headphones by depressing the L-R/MON button above the headphone level control.
CONNECTIONS
The AUX SEND should be connected to the input of an effect processor. The MON SEND should be
connected to the input of the on-stage monitoring system (unless the built-in amplifier is to be used instead,
as described above). The output from the effect processor connected to the AUX SEND can be connected
to either the STEREO RETURN or a spare LINE input. The benefit of using an input channel is that EQ is
available for the signal, but on the other hand, using the STEREO RETURN leaves all inputs free for
instruments.
3:6 THE GRAPHIC EQUALISERS
Each of the 7-band GRAPHIC EQUALISERS are assigned to the left and right busses. For maximum
flexibility, input channels can be individually sent via the GRAPHIC EQUALISERS to the left and right
busses.
The TRIM FADER on each equaliser allows the signal level into the equaliser to be adjusted. This is only
required when excessive EQ adjustments either cause clipping, or severe reduction of the mix level (seen
on the LEFT & RIGHT LED meters).
3:7 TAPE RECORD & PLAYBACK SOCKETS
These are used for making tape recordings of live sessions, playing backing tapes or for playing pre-
recorded background music during intervals etc.
On playback the signal is routed to the left and right busses, its level on these busses set by the LEVEL
control. It can also be sent to the MON system by turning clockwise the TO MON control. Using both these
controls means that a backing track can be sent to both the main mix, and also to the performers.
3:8 PHANTOM POWERING
The POWERHOUSE has a +48V phantom powering facility. When the phantom power switch is ON, 48V is
applied to pins 2 & 3 of all the MIC INPUT XLRs. This is used for remote powering of condenser/ capacitor
microphones which eliminates the need for external microphone power supplies.
A balanced microphone which does not need phantom power will not usually be damaged by being used
while the 48V power is on (there are a few exceptions to this though, and if in doubt contact the microphone
manufacturer).
An unbalanced microphone MUST NOT be used with phantom power ON.

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3:9 THE OUTPUTS
There is a choice of two outputs for the main stereo mix on POWERHOUSE consoles; the LINE OUTS, and
the amplifier OUTPUTS.
The amplifier OUTPUTS in most cases would be used to drive the main P.A. loudspeakers (the L-R/MON
button below the TO AMP level control must be released). However, more power may be required for the
P.A. system in which case amplifiers may be connected to the LINE OUTS. The built-in power amplifier may
then be used to drive the MON (foldback) system (the L-R/MON button below the TO AMP level control
must be depressed).
NOTE: When the amplifier is assigned to MON both channels are driven by the same signal (because the
MON system is mono).

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4:1 DIGITAL REVERBERATION
When live music is played in a concert hall, the sounds of the instruments and vocalists become sustained
and blend into one another. This is due to the sounds being reflected from the walls, ceiling and floor of the
hall and bouncing between these surfaces many times until the "echoes" die away. This effect is called
REVERBERATION.
Many performance venues have poor acoustics; often caused by their internal surfaces not being reflective
to sound. The performance may sound- unnatural and synthetic. Devices for creating artificial "concert hall"
reverberation have been used for many years in the forms of electro-mechanical spring or metal plate based
systems. Apart from being bulky and prone to external noise and vibration, these devices were invariably
noisy, had a poor frequency response, a very limited range of reverb sounds, and in particular an
unconvincing and unnatural sound.
High-speed computer technology has changed all that, allowing acoustic environments to be simulated with
breathtaking accuracy by digital signal processing techniques. In a DIGITAL REVERB, the sound signals
are represented as strings of digital numbers, just like in a compact disc player. A very fast arithmetic
processor continuously performs the millions of calculations every second necessary to synthesise the
many echoes found in natural reverberation. The results of these calculations are then converted back to
analogue sound.
The versatile digital reverberator built in to POWERHOUSE consoles not only provides facilities for
recreating various acoustic environments, but also has some special effects in its 127 program memory.
4:2 THE CONTROLS
1 The TYPE button, and the 8 LEDs above it, are used to select the type of acoustic environment (top
6 LEDs), or various effects (bottom 2 LEDs).
2 The BANK SELECT button. This button is used to toggle between two "banks", indicated by the two
LEDs next to it. When the right LED is lit DARK is selected for the first 6 reverb TYPES. The
selection of "DARK" brings a digital filter into operation, resulting in a more mellow sound. Selecting
DARK also selects the DELAY and SPECIAL EFFECT modes when one of the bottom two TYPE
LEDs is lit.
Selecting the left LED for BRIGHT reproduces the first 6 reverb types without the filter, and is used to
select GATED and REVERSE reverb types.
3 The TIME button, and the 8 LEDs above it, are used to select the decay time of the reverb sound,
the delay time in DELAY mode, or the type of effect in SPECIAL EFFECT mode.
4 The O/LOAD LED indicator gives an impression of the input level and warns of any possible
overload condition.
5 The ON/OFF button allows the reverb to be in-circuit or bypassed. When depressed, the reverb is
in-circuit (ON), and the adjacent LED will light.

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4:3 TECHNICAL DATA
TABLE 1 - TIME SETTINGS
DECAY/GATE/DELAY TIME (Seconds):
TYPE
TIME
SETTING SMALL HALL LARGE HALL SMALL ROOM LARGE ROOM PLATE 1PLATE 2GATED REV- ERSE DELAY
1 0.5 1.2 0.3 1.5 0.2 1.0 0.2 0.1 0.05
2 0.8 2.0 0.5 2.5 0.3 1.5 0.3 0.2 0.1
3 1.0 3.5 0.8 3.0 0.5 2.0 0.4 0.25 0.18
4 1.2 5.0 1.0 4.0 0.8 2.5 0.6 0.3 0.2
5 1.5 6.0 1.2 4.5 1.0 3.0 0.15 0.35 0.35
6 1.8 7.0 1.5 5.0 1.2 5.0 0.25 0.4 0.4
7 2.5 8.0 1.8 7.0 1.5 5.5 0.35 0.45 0.5
8 3.0 15.0 2.0 8.5 1.8 7.5 0.45 0.5 0.65
TABLE 2 - SPECIAL EFFECT PROGRAMS
TIME
SETTING EFFECT
1 Regenerative Reverb
2 Room Ambience
3 Echo and Reverb
4 Stereo Crossing Echo
5 2-Tap Stereo
6 3-Tap Panning
7 Multitap
8 Reverb Bypass
4:4 IN USE
The HALL TYPES tend to be useful for general purpose overall reverberation, and in particular for strings
and brass instruments. The ROOM TYPES are slightly less smooth, and are useful for a more intimate
sound on vocals and guitar. The PLATE TYPES are very smooth and slightly shrill; ideal for vocals or
percussion.
Selecting DARK simulates the more mellow effect of a room filled with a sound-deadening audience or
carpets, curtains, soft furnishings etc. This can be useful for making the reverberation sound less "cutting",
allowing more of it to be used.
On these normal reverb settings, the SPECIAL/TIME button selects the decay time as shown in TABLE 1.
The GATED TYPE simulates the effect of a plate reverberator treated with a noise gate so that the
reverberation tail ends abruptly rather than decaying gradually. This is very effective on percussion such as
snare or bass drum.
The REVERSE TYPE simulates the effect of playing a tape backwards, which can be useful as a special
effect on vocals or guitar for instance. The build-up time is varied using the SPECIAL/TIME button (see
TABLE 1).
The GATED and REVERSE reverb TYPES (or algorithms) have no corresponding "dark" setting.

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When the right BANK is selected, the GATED position becomes DELAY, with a range of normal digital
delays as shown in TABLE 1. The REVERSE position becomes SPECIAL.
When SPECIAL is selected, the various effects listed in TABLE 2 become available on the various positions
of the TIME control.
4:5 SPECIFICATIONS
Frequency Response 20Hz to 10kHz +4-1dB * (Effect) , 11Hz to 25kHz +/-1dB (Dry)
T.H.D. 0.1% (1kHz 0dBm, effect)
Output Noise -71dBm (DIN Audio) +4dBm mode, -82dBm (DIN Audio) -10dBV mode,
-98dBm (DIN Audio) Dry
Maximum Output Level +14dBm (1kHz, 600ohm) +4dBm mode, +2dBm (1kHz, 600ohm) -10dBV
mode
Stereo Separation 100dB (1kHz), 92dB (10kHz)
Input Impedance 100kohm
Reverberation Time 0.2 to 15.0 seconds
Maximum Delay Time 650ms
Headroom Indication 6dB below clipping
* - Includes a small "presence" peak

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5:1 MIXING CONSOLE SPECIFICATIONS
TOTAL EQUIVALENT INPUT NOISE (DIN Audio)
150ohm source MIC Input : -129dB
10kohm source LINE Input : -99dB
COMMON MODE REJECTION RATIO
MIC Maximum Gain @ 1kHz : 87dB
MIC Maximum Gain @ 100Hz : 77dB
TOTAL HARMONIC DISTORTION & NOISE
MIC Gain 50dB Master Output 0dBm into 600ohms : Less than 0.05%
FREQUENCY RESPONSE (+0-1dB)
MIC Gain 50dB Master Output OdBm into 600ohms : 35Hz - 20kHz
INPUT IMPEDANCE
MIC Input Impedance : approx 2kohms
LINE Input Impedance : greater than 20kohms
GAIN RANGE
MIC Gain Range : +15 to +60dB
LINE Gain Range : -5 to +40dB
SIGNAL TO NOISE RATIO
MIC Input to Master Output : 77dB (ref. to 0dBm output)
(MIC Gain 50dB, Output Faders at "O")
CROSSTALK
Input to Adjacent Input : Below Noise
Left Master to Right Master : -68dB @ 1kHz
Input Pan Attenuation : -65dB @ 1kHz
NOMINAL NOISE (DIN Audio)
Master Output Faders at "0" : -87dBm (8 or 12 inputs)
MAXIMUM GAIN
MIC Input to Master Output : 80dB
LINE Input to Master Output : 60dB
NOMINAL OUTPUT LEVEL
Master Outputs : 0dBm/0.775Vrms
MAXIMUM OUTPUT
Master Outputs into 600ohms: +20dBm/8Vrms
HEADPHONES OUTPUT
Into 400ohms : 8Vrms (160mW)
Into 600ohms : 8.4Vrms (115mW)
TAPE RECORD/PLAYBACK
Line In Sensitivity : -10dBV 300mVrms
Line Out Level (Min. load 5kohms) : -10dBV 300mVrms

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INPUT EQUALISATION
Treble (HF) +/-16dB : 12kHz shelving
Midrange (MID) +/-16dB : 2kHz peak response
Bass (LF) +/-16dB : 60Hz shelving
PEAK/CLIP
Dynamic Operation : Indicates 4dB prior to clip
METERS
VU response 12 segment, 2 colour LED
meters with "0" reference : 0dBm
FADERS
Sealed Carbon Track : 60mm
5:2 AMPLIFIER SPECIFICATION
POWER OUTPUT
Both Channels Driven: 4 ohm - 300Wrms
8 ohm - 160Wrms
FREQUENCY RESPONSE
+0-1dB 8Hz to 80kHz
+0-3dB 4Hz to 100kHz
TOTAL HARMONIC DISTORTION
At rated power output (1kHz test signal): 0.02%
INPUT IMPEDANCE: 10kohm
INPUT SENSITIVITY: 0dBm
RESIDUAL HUM NOISE: -70dB
SIGNAL TO NOISE RATIO: Greater than 100dBm
PROTECTION: Dual slope protection against short circuit, open
circuit and load mismatch conditions. D.C. and
thermal protection via relay circuit.
POWER REQUIREMENTS: 600 VA
COOLING: Thermostatically controlled fan
5:3 GRAPHIC EQUALISATION SPECIFICATION
+/-12dB at 60Hz, 150Hz, 400Hz, 1kHz, 2.5kHz, 5kHz, 10kHz
5:4 DIMENSIONS (WxHxD) AND WEIGHTS
8-2 - 530mm wide x 180mm high x 440mm deep, 25kg
12-2 - 650mm wide x 180mm high x 440mm deep, 27kg

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6:1 GLOSSARY OF TERMS
AC POWER INPUT Local electrical supply.
ATTENUATE To reduce a signal, or reduce gain.
AUTO-PANNER A device which automatically moves an instrument between left and right. Can be
triggered manually, or by another instrument connected to its sidechain.
AUXILIARY SEND Extra output from the console, normally used for sending a mix of various instruments
to effects or foldback systems.
BUSS This carries a signal, or sum of signals through the console eg "left" buss.
COLD The negative phase of a signal. With 2 signal wires, one is positive (hot), and the other
is negative (cold).
COMPRESSOR A device which literally compresses a signal so that its level can fit onto media which
have a narrow dynamic range. Compression is often needed before recording onto
cassette tape, and is very useful for vocals.
CONDENSER MICROPHONESHigh quality microphones, generally best suited to recording work. To use with
POWERHOUSE, switch on the +48V Phantom Power.
dB (DECIBEL) A logarithmic ratio used to represent voltage or power gain. The reference to which
the ratio is being made is usually stated.
DIGITAL DELAY A device which samples a piece of sound, stores it digitally, then converts it back into
sound a short time later.
DRY A signal which has not been sent to an effect (see also WET).
EFFECT A general term used to refer to an external piece of equipment which can be used to
"fix" signals which sound wrong (noise gating for example), or used creatively to
produce an "effect" (reverb for example).
EFFECTS SEND See AUXILIARY SEND
EFFECTS RETURN Any place where effects may be returned to the console for mixing; on the
POWERHOUSE consoles there are LINE inputs and STEREO RETURN which are
suitable for this purpose.
EQ (EQUALISATION) Refined tone controls. Each "band" of EQ can adjust a particular frequency to make it
more or less prominent.
FADER A slider, rather than rotary, volume control.
FEEDBACK This is normally caused by a microphone being too close to a speaker. Feedback is an
"endless loop" in which an "output" (from a speaker) gets accidentally fed back into an
"input" (microphone). This can be a deafening howl, or sometimes in headphones a
whining noise will be added to the sound.
FLAT EQ Equalisation has been set so that no frequencies have been boosted or cut - every
frequency is at the same level.
FOLDBACK A separate mix for the performers to hear consisting of live instruments, pre-recorded
backing tracks and sometimes effects returns. The MON system of the
POWERHOUSE consoles is designed for this purpose.
FREQUENCY SPECTRUM The entire range of frequencies from very low (sub-bass and bass) to very high
(treble).