Joemeek TwinQ User Manual

Place

Stamp

Here

JOEMEEK

D I S T R I B U T E D BY PM I A U D I O G R O U P

23775 Madison Street

Torrance, California 90505 USA

TWIN

Q

Joemeek User Guide

3

JOEMEEK reborn – the legend grows

The Next Generation of Joemeek studio processors represents a quantum
leap in the history of the Joemeek legend. Long regarded for its “Big Sound”,
the original Joemeek gear was both revered and reviled for its somewhat
“quirky” nature. Now we have taken the best of what made the Joemeek
products sound great, refined it, distilled it, added to it and repackaged it.

Properly and robustly engineered for predictable, controllable performance,
the new range retains the famous Joemeek sound, with its wide, flat frequency
response extending from subsonic to ultrasonic. It also uses genuinely low
noise circuitry, with lots of headroom (immunity to overload). Accurate cali­bration and metering, together with clear panel labelling, give you complete
confidence in what’s going on. While some equipment pays lip-service to
quality and “professional rules” but fails to deliver, the Next Generation of
Joemeek products are founded on good solid electronic and audio engineering,
and withstand direct comparison with the very best names in mixers and
outboard gear.

The Joemeek range provides everything you need to get your performance
onto tape/disc.

About the Designer

The Next Generation of Joemeek has been completely re-engineered by
renowned audio electronics consultant Allan Bradford. With his background
in physics and 30 years experience with the design of instruments, mixers,
processors and amplifiers, Allan’s unique range of expertise ensures that
Joemeek remains at the forefront of music technology.

Joemeek is manufactured and

marketed under the direction of:

PMI AUDIO GROUP

USA: 23775 Madison Street

Torrance, California 90505

toll free: 877-563-6335

fax: [phone]

email: [e-mail]

UK: P.O. Box 358

Torquay, Devon TQ2 5XS

tel: [phone]

email: [e-mail]

Written by Allan Bradford, MSc

Joemeek® is a registered trademark of PMI Audio Group.

©2004 PMI Audio Group. All rights reserved.

Contents

twinQ Controls at a Glance..............................................4

Overview............................................................................6

Preamplifier........................................................................6

Insert Point..........................................................................7

Compressor.......................................................................8

Meequalizer.......................................................................10

Output Stage.....................................................................10

Using the twinQ..............................................................12

Getting Connected.............................................................12

Using the Preamp...............................................................12

Using the Compressor.......................................................13

Using the Meequalizer.......................................................13

Using the Output Stage......................................................13

Troubleshooting..............................................................14

Technical Specification...................................................15

4

48V PHANTOM POWER switch – feeds 48V power to the microphone XLR
connector. Most condenser microphones require phantom power to operate.

IRON switch – selects transformer coupling of the Mic (XLR) input.
The LED lights when active.

PAD switch – selects 20dB attenuation of the Mic (XLR) input.
The LED lights when active.

LINE switch – selects the Line and INSTRument (1/4” jack) inputs instead
of the Mic (XLR) input. The LED lights when active.

Ø switch – reverses the phase of all inputs.

INSTRument input – high impedance input. Plugging in here overrides

anything plugged into the Line input.

PREAMP GAIN – sets the amount of audio amplification. Too little gain and
the sound will be too quiet; too much and the signal could become distorted.

PEAK LED – lights 6dB below clipping.

HPF - “high-pass filter” – Mainly for use with microphones, this helps

remove stage rumble, handling noise and “pops”. The LED lights when active.

COMPRESS – sets the level of signal (or “Threshold”) above which the
signal starts to be compressed.

SLOPE – sets the compression ratio applied to signals above threshold.

ATTACK – sets how quickly the compressor responds to peaks above

threshold.

RELEASE – sets the time taken for the signal to return to its normal size
after compression. In general, the longer the time, the less obvious the
compression.

MAKE UP GAIN – restores the level of the signal after compression.

COMP switch – turns the compressor on. The LED lights when active.

LF – controls the volume of Low Frequencies or “Bass” in the audio

spectrum. 15dB of boost or cut is available at the selected frequency.

LF FREQ – sets the frequency at which the LF control operates,
anywhere from 40Hz to 650Hz.

MID – controls the middle frequencies in the audio spectrum.
15dB of boost or cut is available at the selected frequency.

MID FREQ – sets the frequency at which the MID control operates,
anywhere from 300Hz to 5kHz.

HF – controls the volume of the High Frequencies or “Treble” in the audio
spectrum. 15dB of boost or cut is available at the selected frequency.

6kHz switch – sets the frequency at which the HF control operates,
in for 6kHz, out for 12KHz. The LED lights when in.

EQ switch – turns the equalizer on. The LED lights when active.

OUTPUT GAIN – the volume control or “Fader” for the output of the twinQ.

PEAK FSD LED – lights 6dB below clipping. “FSD” means “Full Scale

Digital” and this LED also warns you if the Digital Interface is about to be
overloaded.

METER – analogue movement shows output signal level (VU), preamp
signal level or the amount of gain reduction (GR) in dB, depending on the
settings of the Meter switches. The momentary “PRE” switch overrides
both “VU” and “GR” metering.

COMP LINK – for stereo work, Channel 1’s “Compress”, “Attack” and
“Release” control both channels (the corresponding Channel 2 controls
are redundant). This avoids stereo image shifts. All other controls still
operate independently on both channels and must be set the same for
correct stereo balance.

‘EXT CLK’ LED – illuminates when the twinQ’s digital output is
successfully locked to an external word clock.

+4dBu/-10dBv switch – selects the operating level of the 1/4” jack output,
either to the professional +4dBu level, or to the -10dBv semi-pro level.

twinQ Controls at a Glance

6

Overview

The Joemeek twinQ is like having two channels of a professional recording
studio in one box. It takes microphones or instruments, amplifies them,
compresses and equalizes them ready to be recorded. Simple to use yet
extremely powerful, the twinQ will bring out the best in any microphone or
instrument and give the gloss of a professional studio production to all your
performances. As well as recording it will also be found useful for live work.

Think of the twinQ as four separate items of equipment:

• The Preamplifier

• The Joemeek Optical Compressor

• The Meequalizer

• The Fader

Preamplifier

This is the all-important front end to the twinQ. Its job is to accept any
type of microphone, instrument or other source of audio signal, and make
it loud enough. Microphones often need rather a lot of amplification, while
guitars, keyboards and CD players need less. Mics need to be connected
to low impedance inputs, while instruments prefer high impedance inputs.
To ensure correct impedance matching, the inputs are split into an XLR
connector for Mics, and 1/4” jack “Line” and “INSTRument” connectors for
everything else. A switch on the front panel decides which input connector is
active, the XLR or the 1/4” jacks. The LED next to the switch lights to show
that the Line inputs (jacks) are selected. In other words:

Switch out (LED off) = “Mic”
Switch in (LED on) = “Line” or “Instr”

Both Mic and Line inputs are electronically balanced. Note: although the
Line input is not normally used for microphones, it can also be suitable
for some high output unbalanced microphones, such as battery
powered Electret types.

The Mic input (XLR) is balanced and wired as follows:
Pin 2: + (hot)
Pin 3: - (cold)
Pin 1: ground

The Line input (jack) is balanced and wired as follows:
Tip: + (hot)
Ring: - (cold)
Sleeve: ground

The front panel Instrument input (jack) is balanced and wired as follows:
Tip: + (hot)
Sleeve: ground (NB: use a mono jack plug).

Note that if something is plugged into the Instrument input, anything
plugged into the rear panel Line input will be cut off.

PHANTOM POWER

Most high-quality studio mics are “Phantom powered”, which is to
say they have electronics inside them, which get their power from the
preamp. Most mics require a supply of 48 Volts, so Phantom Power is
often labelled “48V”. The “48V” switch turns this power on or off and
a red LED lights when active. When switching the Phantom Power
on, quite a loud thump may be produced, so it is a good idea to turn
down the Output Gain (or to momentarily select the Line input), when
pressing the switch. When using dynamic or ribbon mics, do not turn
Phantom Power on. It probably won’t do any harm but it certainly won’t
do any good, so leave it off! Consult the microphone handbook if you
are unsure what kind of mic you have.

The main control, labelled “Input Gain”, covers a range of amplification
from 10dB to 60dB. In many other preamps the action of the Gain control
is rather uneven, with the 40dB to 60dB range being crammed into the last
1/6th of a turn. All Joemeek preamps use a specially designed control that
ensures smooth operation over the whole range of rotation. The (0) symbol
next to the 25dB mark, means unity gain, or 0dB, for a signal in the Line
input. Hence for Line inputs the range of gain adjustment either side of this
mark, is +35dB, -15dB.

The PEAK LED lights 6dB below clipping, so occasional brief flashes are
OK but if it’s on all the time you need to back the Input Gain off!

HPF means “high-pass filter”. Mainly for use with microphones, this helps
remove stage rumble, handling noise and “pops”. The LED lights when active.

TECHNICAL STUFF

Very low noise - does it matter? Yes and no, it all depends what you are
doing - what really matters is “signal-to-noise ratio”. All electronics produce
a certain amount of background noise - it’s in the nature of things. Providing
there is only a relatively small amount of noise, the signal will cover it up, or
“mask” it. So providing the signal is much bigger than the noise, you won’t
be aware of the noise. In other words the “signal-to-noise ratio” needs to be
a big number, ideally such as 80dB or 90dB.

So how do you achieve that in practice? The trick is to keep the microphone
as close to the sound source as possible without overloading it, so as to get
as much signal out of it as possible. Then you set the Gain control to give
only as much gain as is needed to get a decent level into the recorder.

Of course when there is no signal going on, you may hear the background
noise of the electronics. In that case, given the amount of gain in a typical

The twinQ microphone preamplifier uses state-of-the-art electronics and
has an equivalent input noise of around -128dBu (with 150ohm input
load). Despite all the hyperbolae and obfuscation, the theoretical best
possible performance for silicon-based electronics is about -132dBu.
So the preamplifier design used in the twinQ and all other NextGen
Joemeek products approaches this limit. To improve significantly on this
would require highly specialised electronics and probably a vat of liquid
Nitrogen to cool it!

The maximum gain available from the preamp is 60dB, in which case
the noise floor will be -68dBu. This is actually quite noisy - if you record
that noise onto a digital recorder and play it back you can definitely
hear it. In practice of course, you do not record and play back “silence”
and the rest of the mix will probably be more than 70dB louder than
this noise and will mask it completely. Even so it is generally a good
idea not to use gains greater than 40dB or 50dB and indeed, it should
rarely be necessary to do so.

Insert Point

This is simply an unbalanced “Send and Return” jack on the rear panel.
It allows you to patch any other pieces of equipment into the signal
path, such as an effects processor or noise gate. To use it you will need
a “Y” lead wired as follows:

Tip: send
Ring: return
Sleeve: ground

Compression Ratio

What?? OK, it’s simpler than it sounds. If the input gets 10dB louder but the
output only increases by 5dB then the compression ratio is “2 to 1”. If the
input goes up 10dB but the output only goes up 1dB, then the compression
ratio is “10 to 1”. In a theoretically ideal compressor, this ratio is the same
for any size of signal above the threshold but for that to be true, the gain
cell and its control circuitry must be perfectly linear over a very wide range.
In practice only compressors based on VCAs and digital potentiometers are
likely to behave in this way.

Some compressors have a control to set the ratio anywhere between 1:1
(ie: no compression), and 20:1 (which would be regarded as a “brick wall
limiter”). In the twinQ the “Slope” or “Compression Ratio” is variable from
1:1 (ie: no compression) to 10:1. Slopes around 3:1 are gentle for vocals
while higher slopes are hard for drums and guitars. However that’s not all
there is to it.

Variable Ratio

In the Joemeek optical compressor the compression ‘threshold’ is not clearly
defined and the compression ratio varies with the amount of compression
applied. Suppose the ‘Slope’ control is set to 5:1. For signals only just
exceeding threshold, the ratio is little more than 1:1. As the compressor is
driven harder, the ratio rises to 5:1, at least up to a point. It is a feature of
the Joemeek compressor that the compression ratio actually reduces again
during large transients and, adjusted correctly, this helps to retain bright­ness that is often lost with other types of compressor. This is why vintage
compressors often sound more lively than their modern counterparts.

Controls

‘COMPRESS’ sets the level of signal (the “Threshold”) above which the
signal starts to be compressed. Turning the COMPRESS control clockwise
lowers the compression threshold, and drives the compressor harder.

‘SLOPE’ sets the average compression ratio applied to signals above
threshold. Lower settings (anti-clockwise) have less effect. Turning the

more dramatic. At maximum (10:1) the Joemeek compressor effec­tively becomes a limiter.

‘ATTACK’ sets how quickly the compressor reacts to peaks above
threshold. Turn this control anticlockwise for a quick response. Slower
(clockwise) allows the fast leading edge of percussive sounds to pass
uncompressed for a moment, before the compressor reacts to control
the gain. This example of “changing the envelope” of a sound exag­gerates the percussive nature of drums and other instruments. Settings
around mid-position are used where the compression needs to be less
obvious. Vocals for example, require Attack times around 10msec for
natural sounding results. Faster attack times (anti-clockwise) in
conjunction with large amounts of compression, result in extreme
“pumping” effects.

‘RELEASE’ sets how long the compressor goes on squashing the
sound for, once the signal has dropped below threshold. If it stopped
instantly there would be very noticeable modulation or “pumping” of the
sound. So we may want it to stop compressing less abruptly and that is
what the Release control is for. Generally, the longer the Release time,
the less obvious is the compression. Of course some “pumping” might
actually be desirable as a special effect and that is another way in
which the envelope of a sound can be modified. The twinQ Release is
variable from 100mS up to 3 seconds giving a wide variety of effects.

How the compressor behaves actually changes with programme
content and volume. So experiment with the controls with different
kinds of material to discover the range and depth of effects that can
be achieved. The ‘COMP’ in/out switch allows comparison between
compressed and uncompressed sound (blue LED lights when active).
Remember that the ‘MAKE UP GAIN’ is there to restore the level of the
signal after compression. Correctly adjusted, there will be no change
in volume as the Comp in/out switch is operated.

The Compressor is after the Preamplifier and the Insert Point, and

8

Compressor

The hardest device to understand, yet one of the most useful, the
PhotoOptical Compressor is what gives Joemeek products their unique
character. Its job is to make quiet sounds louder and loud sounds quieter,
or in other words to reduce the dynamic range of the programme material.
It’s a bit like manually riding the volume control, except the compressor
does it automatically, responding far quicker and more accurately than you
ever could by hand. The compressor is applied in several ways:

1. Make Sounds Stand Out

Because compressors make loud sounds quieter, you can boost the volume
of the quiet bits without the loud bits getting even louder. That means you
can raise the average level of an instrument or vocal in the mix, which has
the effect of lifting it and bringing it forwards. This can actually improve
vocals for example, bringing them out in front of a mix, making them sound
denser, more even, and more confident!

2. Crank Up The Volume

Raising the average volume of whole mixes means they can be heard in
noisy environments, such as vehicles and factories. Boosting the average
level is what makes radio stations sound LOUD and the same technique is
used on TV commercials too, which is why they always seem annoyingly
louder than the movie you were trying to watch!

3. Protection

Fast response times are generally used to control brief transients. In other
words if an occasional peak sticks its head above a maximum permitted
level, the compressor clobbers it; this is known as limiting and a compressor
designed solely for this purpose is known as a Limiter. Limiters are primarily
used to protect recorders and monitor systems from overload, radio trans­mitters from overmodulation, etc. The Joemeek compressor is not primarily
intended for this purpose as the Attack is not really fast enough to satisfy

radio station requirements, although it is generally good enough to protect
recorders and monitors, where the effect of transients is less critical.
Normally you should not hear a limiter operating but if it is driven hard
constantly, it can render a mix somewhat flat and lifeless.

4. Accommodation

The dynamic range of the human ear is phenomenal, extending from
the threshold of hearing (eg: a pin dropping onto soft carpet) to threshold
of pain (eg: standing next to a jet aircraft) - some 120dBA in all. By
contrast, vinyl, cassette tape and radio broadcasts all have a dynamic
range of about half that. Since the advent of the CD, the dynamic range
of the medium is far less of an issue and compressors are used more
to give a certain “feel” to a production. AM and FM radio however, is still
very much compressed to fit its restricted dynamic range.

5. Modification

A compressor can change the dynamics, or “envelope” of the track and
it is here that the Joemeek Compressor excels!

Types of Compressor

Most compressors work in essentially the same way: a volume-controlling
element or “gain cell” is inserted into the audio signal path. The level
of the signal at any given moment is measured and that information is
used to control the gain cell. So if the signal gets bigger, the volume is
turned down. Various types of gain cell in common use include FETs,
valves (tubes), light-dependent-resistors (photoelectric), digital potenti­ometers and voltage-controlled-amplifiers, better known as VCAs.

The twinQ Compressor is a unique recreation of the sort of photo­electric compressor used by record producer Joe Meek in the 1960’s.
Using modern components for consistency and reliability, it none­theless reproduces faithfully the same punchy sound that was so
characteristic of the pop records of that time.

plug in a mono jack plug. Either way, this increases the gain of the “+” signal
by 6dB, so there is no drop in level compared with balanced gear.

All outputs on all NextGen Joemeek products are properly balanced, which
is to say there is a signal on both pins! In this way the maximum possible
common-mode rejection of interference, can be achieved at the receiving end.

‘COMP LINK’

This is important when both channels of the twinQ are used together for
stereo work. When two mono compressors are used for stereo, differing
amounts of gain reduction occur in each channel, which causes the stereo
image to wander. The “Comp Link” switch avoids this problem by summing
the compressor control paths and slaving control of Channel 2’s gain cell
to Channel 1. The “Compress”, “Attack” and “Release” on Channel 1 then
operate both channels and the corresponding Channel 2 controls are
redundant. Note however that all other controls still operate independently
on both channels and must be set the same for correct stereo balance. The
LED lights when active.

METER

The analogue meter displays one of three things, depending on the setting
of the “METER” switches.

In VU mode (GR switch out), the Meter shows signal level at the outputs,
after the Output Gain fader. Note that this is relative to the selected operating
level of “+4dBu” or “-10dBv”. In other words if you have selected “+4dBu”
and the meter reads “0”, then you have +4dBu coming out of the 1/4” jack
output socket. If you have selected “-10dBv” and the meter reads “0”, then
you have -10dBv coming out of the output jack.

In Gain Reduction mode (GR switch in), the Meter changes to read “0”dB,
when no signal is present. Whenever the compressor reduces the gain of
a signal, the meter then moves “backwards” to show the amount of gain

The third mode “PRE” allows the output of the preamp to be metered
directly, rather like the “PFL” button on a mixing console. This is useful
for adjusting the gain of the Preamp. The momentary ‘PRE’ switch
overrides both ‘VU’ and ‘GR’ metering.

DIGITAL INTERFACE

The Joemeek Digital Audio Interface provides high quality digital audio
outputs plus the ability to synchronize to an external word clock. The
digital audio outputs are compatible with most digital recorders, as well
as Digital Audio Workstations and mixers. S/PDIF format is available
from the optical and RCA phono connectors, while the transformer
coupled XLR connector provides an AES3 compatible output.

The Joemeek Digital Interface has highly stable onboard master clocks
for low-jitter, hi-fi results. Internal sample rates of 44.1kHz, 48kHz,

88.2kHz or 96kHz are selected by means of rear panel switches.

44.1kHz is the standard used for audio CD’s, while 48kHz and 96kHz
are widely used in recording studios. In general, the higher the sample
rate, the better the audio fidelity, but the more disk space is required
for the recording. For example, recording at 96kHz requires twice as
much storage as 48kHz. Consult the manual of your recorder or DAW
as to what sample rates it will accommodate.

Alternatively the twinQ may be set to the frequency of an external
master word clock, generated, for example, by the studio’s recorder or
DAW. When connected to the BNC socket provided, a suitable external
word clock will be detected automatically and will override the twinQ’s
internal word clock. The front panel LED labelled ‘EXT CLK’ illuminates
when the twinQ is successfully locked to an external word clock.

To avoid distortion, care should be taken not to overdrive the input to
the Digital Interface. The red LED next to the Output Gain control is

10

Meequalizer

The twinQ “Meequalizer” is a highly effective, versatile and musically
rewarding three-band equalizer, or tone control system. Each stage allows
boost or cut of up to 15dB around the frequency in question. The “EQ”
switch turns the equalizer on, and the green LED lights when active.

The LF band can be tuned or “swept” anywhere between 40Hz and 650Hz.
This effectively covers the whole range of low frequencies. It may help to
think of it as like a graphic equalizer, only instead of lots of frequency bands,
you have just one, but it can be moved to cover any given frequency band.
Cutting can be used to reduce unwanted LF noise, such as hum or rumble.
Boosting can bring out the warmth and body of bass lines and (especially
around 80Hz) kick drums.

The Mid band can be tuned or “swept” anywhere between 300Hz and
5kHz. This effectively covers the whole range of mid frequencies. Cutting
the Mid can reduce sibilance, boominess or other annoying resonances.
Boosting can bring out the body of a vocal, or the harmonics of instruments.
Increasing or reducing the “presence” of an instrument or vocal in this way,
can appear to move the sound forwards or backwards in a mix.

The HF or treble section is centred at either 6 kHz or 12kHz. Boosting the
12kHz band gives a sense of “air” or “sparkle” to vocals, instruments and
mixes, without boosting harsh upper-mid frequencies. Alternatively with
bass instruments, cutting this band will reduce HF noise such as hiss and
crackle. The 6kHz setting is very effective at controlling sibilance and
reducing harshness, or indeed creating it, for example by boosting the
harmonics of electric guitars.

The Meequalizer is after the Preamplifier, the Insert Point and the
Compressor.

Technical stuff

Each section of the Meequalizer has a peaking or “bell” shaped
frequency response, which will be found to be musically more
satisfying than conventional “shelving” equalizers. The use of bell
curves at LF and HF also avoids boosting subsonics and ultrasonics
which can have adverse effects on other studio equipment, such as
recorders, monitor amplifiers and speakers. The “Q” value of the
peaking filters is 1.9 (or 1 and 2/3 octaves). Zero phase distortion
ensures the best possible audio coherence.

Output Stage

OUTPUT GAIN

This output volume control provides up to 10dB of gain and also
goes right down to nothing, so acting as a fader to fade a sound
out completely.

CONNECTORS

Two outputs are provided, jack and XLR, so you can simultaneously
feed (say) a recorder and a monitor amplifier. The switch adjacent to
the 1/4” jack selects the output operating level to either +4dBu (suits
most professional studio equipment) or -10dBv (suits semi-pro or hi-fi
equipment). The XLR output is always +4dBu. Check with the hand­book for whatever you are feeding, to find out which level is required.

The XLR output is balanced The jack output is balanced
and wired as follows: and wired as follows:
Pin 2: + (hot) Tip: + (hot)
Pin 3: - (cold) Ring: - (cold)
Pin 1: ground Sleeve: ground

Balanced or Unbalanced

To run the XLR output unbalanced, it will be necessary to ground pin
3 of the cable connector. To run the 1/4” jack output unbalanced, just

Using the Compressor

Start with the Compressor and Meequalizer off and adjust the input and
output gain so that the VU Meter reads around 0dB. Now switch the meter
to read gain reduction using the ‘GR’ pushbutton.

Set ‘COMPRESSION’ and ‘ATTACK’ fully anti-clockwise, with ‘SLOPE’ and
‘RELEASE’ at mid-position. Press the ‘COMP’ push-button and turn up the
‘COMPRESSION’ control until the compressor GR meter starts to read 3dB
or 5dB on audio peaks. You should now be able to hear the compressor
working as the volume diminishes. Use the ‘MAKE UP GAIN’ control to
restore the signal to its previous (uncompressed) level. Alter the SLOPE
and listen to how the severity of the gain reduction changes. Try changing
the Attack and listen for percussive sounds getting louder. Reducing the Attack
and Release times should emphasise this even more and the compressor
should start to “pump” audibly.

The overall result of compression depends on the combined settings of the
Compress, Slope, Attack and Release controls. Experiment with different
combinations to discover what best suits the material you wish to compress.
Watch the GR meter and don’t overdo things - it’s possible to apply 20dB of
gain reduction before you realise it!

Use the ‘COMP’ switch to make comparisons between compressed and
uncompressed signals.

Using the Meequalizer

Always start with the Meequalizer boost/cut controls (LF, MID and HF) set
to “0” (the control knobs set vertically, in their centre notches). This setting
is also known as “flat”.

You need to be careful about too much boost or “lift”, since boosting
takes the twinQ closer to overload. The twinQ has generous overload
margins but when a lot of boost is used, it may be necessary to
compensate by reducing the Output Gain or the Input Gain (the latter
will affect the Compressor setting though).

Keep an eye on the VU Meter when adjusting the EQ. When the red
LED (labeled “PEAK FSD”) lights, the twinQ is within 6dB of clipping.
Occasional flashes are OK but if it is on all the time, turn something down!

The way to use the LF FREQ and MID FREQ controls, is to apply quite
a lot of boost, then sweep the frequency until you “tune in” to the sound
you are interested in. Once you find it, adjust the amount of boost or cut
to give the desired effect.

Experiment with combinations of settings of EQ and try to picture how
the audio signal is being affected. Use the ‘EQ’ switch to make compari­sons between EQ’d and non-EQ’d signals.

Using the Output Stage

Final adjustments to the output level can be made with the OUTPUT
Gain control, again keeping an eye on the VU meter and PEAK FSD
LED. Note how this control can also be used to fade out the signal
completely.

12

Using the twinQ

GETTING CONNECTED

The figure shows the twinQ being used instead of a mixing desk in a
recording setup:

• A microphone is connected to the Mic Input

• A guitar is connected to the Instrument Input

• The insert point is being used to divert the preamplified signal through
an external effects processor

• The recorder output is connected to the Line Input for playback.
Previously recorded tracks may also be replayed via the Line Input,
to permit compression and equalization

POWER SUPPLY

Connect the twinQ power cord to the AC connector on the rear panel
and switch on the mains supply. NB: ensure that the twinQ is set to the
correct mains voltage for your region – either 115V or 230V. Orientate
the fuse holder / mains voltage selector draw so that the required voltage
appears at the top. If in doubt consult a competent engineer.

Using the Preamp

Turn the ‘INPUT GAIN’ control to minimum and connect the input
source. If you are using a condenser microphone, remember to switch
on the 48V Phantom Power. Set the ‘OUTPUT GAIN’ to “0dB”. Turn up
the ‘INPUT GAIN’ until the microphone sound registers on the VU Meter,
adjusting it so that the meter reads between “0” and “+3” on sound
peaks. When the red LED (labeled “Peak”) lights, the twinQ is within
6dB of clipping. Occasional flashes are OK but if it is on all the time,
turn the Input Gain down!

Remember you can check the preamp gain at any time by pressing the
“Meter Pre” button.

Technical Specification

Input impedances Mic: 1.2kohm; Line: 20kohm

Pre-amp overall gain 0dB to 60dB

Common mode rejection 70dB

Equivalent input noise -128.5dBu (unweighted)

Distortion 0.001%

(below Compressor threshold)

Frequency response 15Hz to 70kHz (-3dB)

Maximum input before clipping Mic: +21dBu; Line: +45dBu

Headroom before clipping +21dBu

High Pass Filter 12dB per octave cut below 80Hz

Compressor threshold -6dBu to +22dBu (variable)

Compressor ratio 1:1 to 10:1 (variable)

Compressor attack time 1 msec to 100 msec (adaptive)

Compressor release time 0.1 sec to 3 sec (adaptive)

EQ Boost and Cut +/-15dB (zero phase-shift bell response)

LF Frequency 40Hz to 650Hz variable

MID Frequency 300Hz to 5kHz variable

HF Frequency 6kHz or 12kHz selectable

Nominal output levels +4dBu/-10dBv

Output impedance 75ohm

Output Level switch 12dB attenuation

Noise Floor -85dBu (typical, with ~40dB mic gain)

VU Meter Analogue movement

Power supply 115V / 230V ac mains, 50/60Hz

Power consumption 30W

Mechanical 482W x 88H x 220D (overall)

Weight 3 kilos

14

Troubleshooting

1) No Power (no lights work)

• Is the power supply plugged in (both ends)?

• Is the mains power on?

• Is the mains voltage set correctly for your region?

• Has the mains fuse blown?

2) The microphone doesn’t work

• Is it connected to the correct (XLR) input on the rear panel?

• If it is a condenser microphone, is the phantom power switched on?

• Is the ‘Line’ switch out (LED off)?

• Is the ‘Input Gain’ control turned up?

• Is the ‘Output Gain’ control turned up?

3) The line input doesn’t work

• Is the source connected to the correct (jack) input on the back of the unit?

• Is the ‘Line’ switch in (LED on)?

• Is the ‘Input Gain’ control turned up?

• Is the ‘Output Gain’ control turned up?

4) The compressor doesn’t work

• Is the ‘Comp’ switch in (LED on)?

• Is the ‘Compress’ control turned up enough?

• Is there enough signal, as set by the ‘Input Gain’ control, to drive the
compressor?

5) Too little or too much compression

• Turn the ‘Input Gain’ control up or down respectively, to adjust the
signal level to the compressor

6) The Meequalizer doesn’t ‘t work.

• Is the ‘EQ’ switch in (LED on)?

• Is ‘Input Gain’ control turned up?

• Is ‘Output Gain’ control turned up?

7) Too much noise

• Is the ‘Input Gain’ control too high? Try moving the mic closer to the
source

• Is the ‘Output Gain’ control too high (eg: when lots of compression is
being used)?

• Is there too much EQ boost?

• Is the noise already present in the input signal? (Try removing the input)

8) Sounds distorted

• Is the ‘Input Gain’ control too high?

• Is the ‘Output Gain’ control too high?

• Is there too much EQ boost?

• When using the compressor, is the Release control set too low?

replacement by Purchaser of any Product or part thereof shall extend
the warranty period as to the entire Product. The specific warranty on
the repaired part only shall be in effect for a period of ninety (90) days fol­lowing the repair or replacement of that part or the remaining period of
the Product warranty, whichever is greater.

2. Exclusive Remedy: Acceptance: Purchaser’s exclusive remedy and
PMI’s sole obligation is to supply (or pay for) all labor necessary to
repair any product found to be defective within the warranty period
and to supply, at no extra charge, new or rebuilt replacements for
defective parts. If repair or replacement fails to remedy the defect, then
and only in such an event, shall PMI exchange to Purchaser a new or
reconditioned unit. Purchaser’s failure to make a claim as provided in
paragraph 1 above or continued use of the product shall constitute an
unqualified acceptance of such Product and a waiver by Purchaser of
all claims thereto.

3. Exceptions to Limited warranty: PMI shall have no liability or obligation
to Purchaser with respect to any Product subjected to abuse, improper
use, negligence, accident, modification, failure of the end-user to follow
the operating and maintenance procedures outlined in the users manual,
attempted repair by non-qualified personnel, operation of the unit
outside of the published environmental and electrical parameters, or
if such products original identification (trademark, serial number) markings
have been defaced, altered, or removed. PMI excludes from warranty
coverage, Products sold AS IS and/or WITH ALL FAULTS and excludes
used products which have not been sold by PMI to the Purchaser. PMI
also excludes from warranty coverage consumables such as fuses and
batteries, tubes, etc.

Joemeek Limited Warranty

THIS PRODUC T IS FOR PROFESSION AL USE ONLY

PMI Audio Group warrants that all products will be free from defects in mate­rial or workmanship:

A: For a period of (3) three years from the date of purchase (hereinafter the
labor warranty period), PMI Audio Group will repair or replace this Product if
determined to be defective. After the expiration of the labor warranty period,
the Purchaser must pay labor charges.

B: In addition, PMI Audio Group will supply, at no charge, replacements for
defective parts for a period of (three years) from the date of purchase. During
the labor warranty period, to repair the Product, Purchaser must return the
defective Product, freight prepaid, or deliver it to PMI Audio Group Service
Center. The product to be repaired is to be returned in either its original car­ton or a similar package affording an equal degree of protection. PMI Audio
Group will return the repaired Product freight prepaid to the Purchaser. PMI
Audio Group is not obligated to provide Purchaser with a substitute unit dur­ing the warranty period or at any time.

Conditions

1. Notification of claims: Warranty Service: If Purchaser discovers that the
Product has proven defective in material or workmanship, then written notice
with an explanation of the claim shall be given promptly by Purchaser to PMI
but all claims for warranty service must be made within the warranty period. If

Notes

Product Registration Information

Please Fill in the Below Sections and Return

Name:

Address:

City: State: Zip Code:

Telephone Number: email Address:

Model Purchased: Date Purchased:

Serial Number: Dealer:

Comments:

What magazines do you read to influence your buying decision: (please check all that apply)

Disclaimer of Warranty

EXCEPT FOR THE FORGOING WARRANTIES, PMI HEREBY DISCLAIMS AND

EXCLUDES ALL OTHER WARRANTIES, EXPRESS OR LIMITED, INCLUDING, BUT

NOT LIMITED TO ANY/OR ALL IMPLIED WARRANTIES OF MERCHANT ABILITY,

FITNESS FOR A PARTICULAR PURPOSE AND/OR ANY WARRANTY WITH REGARD

TO ANY CLAIM OF INFRINGEMENT THAT MAY BE PROVED IN SECTION 2-312(3)

OF THE UNIFORM COMMERCIAL CODE AND/OR IN ANY COMPARABLE STATE

STATUE. PMI HEREBY DISCLAIMS ANY REPRESENTATIONS OR WARRANTY THAT

THE PRODUCT IS COMPATIBLE WITH ANY COMBINATION OF NON-PMI AUDIO

PRODUCTS PURCHASER MAY CHOOSE TO CONNECT TO THE PRODUCT.

Limitation of Liability

THE LIABILITY OF PMI, IF ANY, AND PURCHASER’S SOLE AND EXCLUSIVE REMEDY

FOR DAMAGES FOR ANY CLAIM OF ANY KIND WHATSOEVER, REGARDLESS OF

THE LEGAL THEORY AND WHETHER ARISING IN TORT OR CONTRACT, SHALL

NOT BE GREATER THAN THE ACTUAL PURCHASE PRICE OF THE PRODUCT

WITH RESPECT TO WHICH SUCH CLAIM IS MADE. IN NO EVENT SHALL PMI

BE LIABLE TO PURCHASER FOR ANY SPECIAL, INDIRECT, INCIDENTAL, OR

CONSEQUENTIAL DAMAGES OF ANY KIND INCLUDING, BUT NOT LIMITED

TO, COMPENSATION, REIMBURSEMENT OR DAMAGES ON ACCOUNT OF THE

LOSS OF PRESENT OR PROSPECTIVE PROFITS OR ANY OTHER REASON

WHATSOEVER.

Owners Registration Card

T O B E C O M P L E T E D A T TI M E O F P U RC H AS E

Name _____________________________________________

Date of Purchase ____________________________________

Serial Number ______________________________________

Dealer’s Name ______________________________________

R E TA IN F O R Y O U R R E CO R D S

P L E A S E D I S P A T C H A N D R E T U R N

Y O U R RE G I ST R AT I O N

T O J OE M E EK W I T H IN 1 4 D AY S

O F P UR C H A SE

Specifications and model numbers are subject to change without notice