“A diode bridge is a very unique sound characteristic compared to other types of compressors. It is possible to create a cleaner sounding diode bridge than we have here, but we were after a particular flavor of harmonic content. As soon as you hear the sound, you know exactly what it is.”
THRESHOLD
A 31-position detented pot that sets the level at which compression begins, from -25dB to +20dB. Turning this control counter-clockwise will increase the amount of compression; turning it clockwise will decrease the amount of compression.
RATIO
The RATIO control has six selectable positions on a rotary switch, allowing the user to set the slope of the compressor curve with pre-selected ratios of 1.5:1 through 8:1 for levels above the determined THRESHOLD. This range of compression ratios allows the user to compress as moderately or heavily as desired.
TIMING
The unified TIMING control is a six-position rotary switch that sets the compressor attack and release times. The timing can be further modified by the FAST button.
FAST (TC1) – Fast Attack (750 μs), Fast Release (130 ms)
MF (TC2) – Medium Attack (2.25 ms), Fast Release (130 ms)
MED (TC3) – Medium Attack (2.25 ms), Medium Release (400 ms)
MS (TC4) – Medium Attack (4 ms), Slow Release (725 ms)
SLOW (TC5) – Slow Attack (10 ms), Slow Release (800 mS - 1 S)
AUTO (TC6) – Medium Attack (5 ms), Dual Release (T1 500 ms, T2 1s)
FAST
The FAST switch speeds up all compressor time constants by 30%, effectively doubling the number of TIMING presets available to the user.
BLEND
The BLEND control has 31 detents and allows the user to mix the uncompressed (dry) signal with compressed (wet) signal. Turning the control towards 0% will shift the mix to fully uncompressed dry signal, whereas turning the control towards 100% will shift the mix to the fully compressed signal. This feature allows for parallel compression, enabling a wide range of compression subtlety.
GAIN
The GAIN control has 31 detents and allows the user to add make-up gain to the compressed signal in order to bring its level back up to unity with the uncompressed input signal. It is much easier to evaluate the tonal effect of the compressor (via the COMP IN switch) when the compressed output level is matched to the uncompressed input level, thereby eliminating potentially misleading level differences.
COMP IN
The COMP IN switch engages the compression circuit. By disengaging the COMP IN switch, the compressor is bypassed and the user can quickly compare the compressed sound to the dry input signal for an objective evaluation of the compressor’s sonic effect on the audio signal.
LINK
The LINK switch allows the compressor to be linked to another 535 compressor module via a side chain control voltage. In link mode, the compressor generating the greater side chain voltage (resulting in higher amounts of compression) will control the compression of both audio signal paths to maintain proper stereo center image while compressing.
SIDE CHAIN HPF
The S/C HPF switch allows the user to insert a 12dB/octave 150Hz high-pass filter in the compressor side chain. When this filter is engaged, the compressor will be considerably less responsive to information below 150Hz. For example: if used on a drum kit, the low end of the kick drum would have less proportional effect on the compression than a snare drum or cymbals, since a significant portion of the kick drum’s dynamic energy is focused below 150Hz.
LEVEL & GAIN REDUCTION METERING
These two LED meters provide highly accurate representations of both the output level of the compressor and the amount of gain reduction being applied to the input signal.
MAXIMUM INPUT LEVEL
+23.5 dBu
MAXIMUM OUTPUT LEVEL
+23.5 dBu
INPUT IMPEDANCE
10K Ohm
OUTPUT IMPEDANCE
40 Ohm
THD+N
@ 1 kHz @ Maximum Output Level, 22 Hz - 22 kHz BW.
0.001%
NOISE
22 Hz - 22 kHz BW, 40 Ohm balanced source. Noise specifications may vary depending on which 500 series chassis is being used, and / or interference from stray magnetic fields.
-101 dBu
FREQUENCY RESPONSE
10 Hz - 120 kHz, 30ft output XLR Cable.
+/- 0.1 dB
COMPRESSOR TIMING CONSTANT MEASUREMENTS
Note: TIMING measurements represent the full range between 1.5:1 and 8:1 ratio and FAST mode
FAST – Attack 250 μS - 2 mS // Release 100 mS - 200 mS typical
MF (MEDIUM FAST) – Attack 1 mS - 5 mS // Release 100 mS - 200 mS typical
MED (MEDIUM) – Attack 3 mS - 18 mS // Release 350 mS - 700 mS typical
MS (MEDIUM SLOW) – Attack 5 mS - 40 mS // Release 600 mS - 1 S typical
SLOW – Attack 10 mS - 80 mS // Release 800 mS - 1.5 S typical
AUTO – Attack 5m S - 40m S // Release T1 400-900 mS, T2 1-2 S typical
POWER CONSUMPTION (+/-16VDC): 100 mA
UNIT DIMENSIONS
1x 500 Series Module: 1.5” W x 5.9” D x 5.25” H
(3.8 cm W x 15 cm D x 13.3 cm H)
UNIT WEIGHT
1.5 lbs. (0.7 kg)
SHIPPING DIMENSIONS
10” W x 8” D x 3” H
(25.4 cm W x 20.3 cm D x 7.6 cm H)
SHIPPING WEIGHT
3 lbs. (1.4 kg)
