IGS Audio Alter 500-Series Compressor
The IGS Alter 500-Series Compressor is an FET compressor built is the 500 standard. The FET-type solution was used for the first its application in the legendary UREI 1176 compressor from the 70s. The Alter is a single-channel unit with stepped input and output controls. The Ratio switch has six positions, including two additional to the original 1176 1:1 and 2:1 settings. Slam Mode can be turned on with a separate switch, working regardless of the Ratio settings. Attack and release times can be set to Fast / Mid / Slow with 3-pole switches. The IGS Alter 500-Series Compressor is equipped with a relay bypass, achieved on the front panel. The input is balanced with a modern, low-noise op amp and the output with a custom IGS transformer transformer. The circuit has two amp stages, between which is the output control. The stage amps are based on the discreet API2520 circuit. The level of gain reduction is shown by a 20 point led bar.
Specification and Features:
Input – Input level and compression depth
Output – Output Level
Attack – Variable Attack – 3 ranges: 0.02, 0.2 and 0.8 ms
Release – Amp recovery time to the value of 0.85 max. Range: 50ms, 600ms, 1.1 sec
Ratio – compression ratio over the threshold response
Ratio ranges: from 1:1 (line amp), through 4:1 (compressor) to 20:1 (limiter)
SLAM – allows the enabling of All-Buttons-On – the “secret weapon” of any studio engineers 😉
COMP IN / OUT – Enable Bypass relay device
GR – very fast LED indicator showing the compression level in the range from 0 to 20dB
IGS Alter 500-Series Compressor Specifications
Device Type:
FET Compressor: Yes
Basic Features:
All Stepped Manipulators: Yes
Input & Output:
Input Impedance (Balanced): 10k Ohm
Output Impedance (Balanced): 600 Ohm
Audio Transformers: Yes, IGS’s own custom transformer
Levels:
Operating Level: +4 dBu
Max Input Level: +20 dBu
Max Output Level: +22 dBu
Noise Level: -99 dBA
Max. Gain: 36 dB
Max Gain Reduction: 20 dB
Time Constants:
Attack: 20us, 400us, 800us
Ratio: 1:1 to 20:1
Release: 50ms, 600ms, 1.1s
Bandwidth:
Fequency Response: 8 Hz to 20 kHz, +/- 0.1dB
Distortion (@ 20 Hz – 20 kHz):
THD+N: 0.012%
Power:
Power Consumption: 2.5W
Packing Box:
Shipping Weight: 1 kg / 2.2 lbs
IGS Alter 500-Series Compressor Includes