General Guidelines on the use of the Classic Opto

One day while Carl was adding some compression to a guitar track in his studio, he thought, why hasn’t anyone built a small opto-compressor for guitarists? An optical compressor performs gain reduction control via a light source into a photo sensitive cell... as the light source gets brighter, the photo sensitive cell sends a signal to reduce dynamic range, or what becomes a compressed signal. Welcome to the Vintage Opto-Compressor….an old-school compressor from the days where colouring was an important factor to the sound. The four controls (from left to right) are the Gain, which controls the ‘pre-glow’ of the optical circuit (the more you turn this up, the fatter the sound); Level, which controls the overall volume of the compressor; Compression, which controls how hard or soft the compression is, and the Attack control which takes the signal from transparent to outright total squeeze. A short time with this compressor will allow you to find some of those classic guitar sounds which may somehow have escaped you before. Again, like all the Vintage pedals, the Opto-Compressor comes in a solid diecast housing with cool chicken-head knobs, CM colour and graphics and a 9v battery compartment. Due to the nature of compressors, we highly recommend a regulated power supply (like the CM Big John) or a large stock of batteries…..

On the Gain knob you adjust how much of the guitar signal you would load the circuitry with, if you set the knob at left the compressor will not be very effective, the more you turn right the more effective the compressor get.
It can go from a very mild soft compression to really hard beefed up compression at full right.
The gain knob will be interactive with the rest of the knobs, so i.e. the harder you load the circuitry, the more effective the comp knob get.

The Level knob you use the adjust the output level from the pedal to match you clean sound when you finished setting the gain,-comp & attack knobs, for the comp effect you want.
The level knob can go from below unity level to several dB boost, so you can actually use the Classic Opto-Comp as a boost sustain pedal, to make your singing lead cut through to the audience.

When you have set the gain knob to the right amount of signal you want to be compressed, you set the amount or degree of compression on the Comp knob, going from nearly nothing at full left, to extreme hard compression at full right, again here note that the efficiency of the knob depends on how the gain & attack knobs are set.
The more gain & attack the more compression you get.

The Attack knob what is that? It's to adjust/set how fast attack/release time shall be, at full left the attack is fast, in this mode the compression is more neutral limiter like. While at full right the compression is much more effective and effect like, the effect will then be more suitable for finger picking style.

Again here note that the attack setting will be interactive with the other knobs.