7
8
NOTE, the amplification range of the instrument input IS affected by the
mic/line push-button; there is more amplification range when it is switched
to 'mic', but the 'line' position is usually adequate.
If the musical instrument output is too 'hot' for the input (even when the
input gain control is turned to minimum and 'line' is selected), then use the
'line' input on the rear of the unit instead.
THE COMPRESSOR
And now for the part of the JOEMEEK 'TwinQ' that gives it character; - the
compressor.
The compressor is a photoelectric device where the sound triggers light
emitting diodes which in turn control the resistance of a photo sensitive
resistor. This form of compression used to be common in the 60's and 70's
but has been superseded by so called 'improved' voltage controlled
amplifiers. The advantages of the older system are that distortion is virtually
nil, noise is extremely low while overload margin is extremely good. The
disadvantages are that the design is more difficult to produce cheaply and,
according to those who judge equipment by specifications and not by
listening, the older design is less flexible in operation and 'more difficult to
use'. JOEMEEK begs to differ!
st
Using 21 century electronics for the control circuitry, Ted Fletcher has
recreated the compressed sound of the 60's; a sound that was unlikely ever
to be heard again. Totally unlike a modern compressor, it can pull voices
forward, help with internal mix balance, and add 'presence' to the sound as
well as controlling recording volume levels. But its main and unique attribute
is its ability to produce the characteristic 60's compressed exciting sound
without losing the transient sparkles that are such a feature of good digital
recording.
THE COMPRESSOR; TECHNICALLY
To get the best use out of the compressor it is necessary to understand the
basic physics and what it is designed to do.
A LIMITER is a device which stops the output of a signal path going above
a predetermined level.
A COMPRESSOR is a device which reduces the dynamic range of
programme material.
WHAT IS A COMPRESSOR?
A perfect compressor is an amplifier where the input/output ratio is
constant: So using a 2:1 compressor, increasing the input by 2dB gives a
corresponding 1dB increase in the output. Early compressors which used
variable mu thermionic tubes or photoelectric devices only approximated
true compression over a limited range. They had a soft 'threshold' where
compression started and held to a predictable ratio up to a certain level,
then they returned to a more linear amplification allowing transients
through. This is in stark contrast to modern VCA compressor/limiters where
designers latched onto the idea that a compressor should be entirely linear
in its compression characteristic (regardless of the sound produced) and
thought it 'sensible' to combine the functions of compressor and limiter to
'stonewall' any and all signals above a certain level.
The musical effect is that VCA compressors sound muddy and flat, while
the historic compressors sound lively and retain sparkle.
But all compressors change the sound to some extent. The JOEMEEK
Studio Channel compressor adds 'punch' and 'bite' without the dull
muddiness of all others.
USING THE COMPRESSOR
A compressor IN/OUT switch is fitted. When this switch is pressed the blue
LED indicator above the switch is activated.
To USE the compressor, set the COMPRESSION control to about halfway.
·
Set SLOPE to number 3.
·
Set ATTACK to halfway,
·
Set RELEASE to halfway the release control at this setting will make
the compressor act to moderately control the gain, at higher
settings, sudden loud noises will cause the signal to remain
compressed for longer thereby restricting the gain more.
·
Switch the VU meter to 'COMP. METER' (switch out). - Don't forget
to turn up the output volume control too. If there is sufficient audio
signal from the input amplifiers, the meter will start to indicate
compression by the needle moving downwards.
twinQ
CS
Dual Recording Channel
- User's guide
