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CHAPTER 4: HOOKUP DIAGRAMS
In this example, a microphone is feeding into a preampflier, which feeds
into the WA76 via a balanced XLR patch cable, which feeds into the LINE
LEVEL input of your recording interface/recorder.
Note: it is important to use a line level input on your recording device
as opposed to a microphone or instrument level input.
4. Release Knob
This sets the amount of time it takes the WA76 to return to its initial (uncompressed) level. The
WA76’s release time is adjustable from 50 milliseconds to 1100 milliseconds (1.1 seconds).
If the release time is too fast, “pumping” and “breathing” can occur due to the rapid rise of
background noise during gain restoration. On the flip-side, if the release time is too slow, a
loud section of the recording may cause compression to occur and continue through a soft section
of the recording (where it is un-needed), making the soft section quiet and difficult to hear.
5. Ratio
These four buttons determine the severity of the gain reduction. (A ratio of 4:1, for example,
means that whenever there is an increase of up to 4 decibels in the loudness of the input
signal, there will only be a 1 dB increase in output level. A ratio of 8:1 means that any
time there is an increase of up to 8 dB in the input signal, there will still only be a 1 dB in-
crease in output level.) Also, true to the classic design, higher ratio settings will also set the
compression threshold at a higher level. This means that, for instance, at a ratio of 20:1,
more of the ‘body’ of a signal will be left uncompressed, but transients above it’s higher
fixed threshold will be more drastically compressed. When higher ratios (12:1 or 20:1)
are selected, the WA76 is essentially acting more as a limiter than as a compressor.
The WA76 can reproduce the classic effect known as ‘All Buttons In’ mode, sometimes also
referred to as ‘British Mode’ or the ‘Four Button Trick’. Originally an accident due to the
mechanical nature of the interconnected latching switches, this mode is reproduced by pushing in
all four ratio buttons simultaneously and getting them to latch. This can take a bit of practice. The
resulting compression curve is aggressive and unmistakably unique, and can be heard on the
drum tracks of many classic recordings. All-buttons-in compression is typically characterized by
having a very aggressive compression ratio, attack and release curves that are more drastic
plateaus opposed to gentler slopes, and more audible distortion or ‘overdrive’ on the signal.
Initial transients are more likely to come through loudly, followed by heavy compression curve
sometimes described as having a ‘sucking’ effect as the compressor releases. Because this
mode is considered a design accident, faithfully maintained; it is normal for the meter function
to ‘peg out’ and cease providing accurate metering. This will not harm the unit or the meter.
The WA76 must have at least one ratio select button engaged in order to function. With no
ratio button engaged, the unit will eventually stop passing audio.
6. Meter
The four buttons under the Meter label power the unit on (or off) and determine what the WA76’s
front panel meter displays. The VU Meter displays either the amount of gain reduction (GR), or the
compressor’s output level which is either +8 or +4. When “+8” is selected, a meter reading
of 0 corresponds to a level of +8 dBm at the rear panel outputs. When “+4” is selected, a
meter reading of 0 corresponds to a level of +4 dBm at the rear panel outputs. Engaging
the OFF switch powers off the WA76 entirely.
CHAPTER 3: TECHNICAL SPECS
WA76
Recording interface
