Universal Audio Volt 476 Hardware Manual page 9

Press these buttons to toggle the Vintage Preamps. The Vintage Preamps
can be used on mic, line, and instrument inputs.
The Vintage Preamp adds a carefully crafted analog tube preamp
emulation, inspired by Universal Audio's all-tube 610 console preamplifier,
to the sound. When the button is lit orange, the circuit is active.
(9) 76 Compressor Buttons
Press these buttons to engage the 76 Compressors. The 76 Compressors
can be used on mic, line, and instrument inputs. The button is lit orange
when the compression circuit is active.
The 76 Compressor lets you add clarity and punch to voice, guitars, and
more, with an analog compressor based on UA's iconic 1176 Limiting
Amplifier.
Press the button repeatedly to cycle through the presets or disable the
circuit (VOC, GTR, FAST, or OFF).
Note: The input level increases when the compressor is active, so you may
want to readjust your Gain setting.
(10) 76 Compressor Presets
The indicators above the 76 Compressor button indicate whether the
compressor is off or enabled on one of the presets. The 76 Compressor
presets have the following characteristics:
Fast attack and slow release for classic smooth vocal
VOC
compression
Slow attack and relatively quick release allows more guitar/bass
GTR
transients