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COMPRESSION PROBLEMS
1)
Got signal going through but no compression.
Is the compressor switched in?
Is there enough signal?
- A good signal is required to make the compressor operate.
Have you turned the COMPRESSION control high enough?
- is the slope switch turned high enough?
2)
It's noisy.
The compressor itself is extremely quiet, but by definition compressors
raise the level of quiet passages; this also means that if there is noise in the
microphone channel (in the audio signal that is being amplified), there will
be more noise on the compressed signal. It's a compromise.
3)
It distorts.
No it doesn't! Distortion inside the compressor is virtually impossible,
however it is possible that the microphone amplifier is set with too much
gain; turn down the COMPRESSION control and readjust the microphone
amplifier gain.
4)
I can't make the compression gentle enough!
It takes practice. The setting of the Attack control close to fastest is quite
critical, as is the compression control. Also, longer release times lead to a
less noticeable compression effect.
THE GAIN MAKE-UP AMPLIFIER
The JOEMEEK compressor is essentially a passive piece of electronics.
That means that under compression, when the audio signals are being
pushed down in compression, there needs to be a high grade amplifier after
it to bring the audio signal back to normal volume.
Additionally, the new 'TwinQ' has a gain make-up stage with an
integral output volume control. The design of this stage is unusual as the
volume control circuit acts around the amplifier minimising any amplifier
noise.
The VU meter operates before the output gain make-up amplifier so that
the VU meter can be used meaningfully at any output volume setting.
MEEQUALIZER
The equalisers fitted to the 'TwinQ' are similar to the original Joemeek Vc5;
that is, a simple shelving High frequency and low frequency equaliser, with
a mid frequency lift and cut, This equaliser is similar to early frequency
correction circuits used in recording studios in the late 1960s. It is musical
in its effect and can produce wide and dramatic variations without
unpleasant side effects.
The equaliser is placed in the circuit immediately following the compressor.
The on/off push-button switches the circuit into operation. The LF (low
frequency) gives shelving lift and cut of up to 15dB at 100Hz. The mid
frequency control gives peaking lift and cut of up to 15dB at approx.1.5KHz.
The 'Q' or bandwidth of the mid is set at approx. 1.1 with the lift or cut at
maximum, so that the effect of all but the most extreme lifts and cuts will be
musically pleasant to listen to. The HF (high frequency) control gives
shelving lift and cut of up to 15dB at 8KHz.
When using the equaliser, bear in mind that lifting any EQ will increase the
volume level in the channel and so can reduce the overload margin. Be
prepared to turn down the input gain to compensate.
BALANCED OUTPUT
The line level output from the Studio Channel is electronically balanced
which has the capability of driving up to +24dB into balanced circuits. The
digital outputs (if fitted) are SPDif. 24 bit.
CONNECTING UP THE EQUIPMENT
MICROPHONE INPUT (REAR PANEL)
The microphone input is an XLR connector. For best results the microphone
used should be balanced 200 ohm impedance Connections are
Pin 1 is ground or screen.
Pin 2 is positive phase or 'hot'
Pin 3 is negative phase (or ground for unbalanced).
To avoid impulsive 'clonks', plug in capacitor microphones before turning on
the phantom power.
twinQ
CS
Dual Recording Channel
- User's guide
