Frequently, guitarists search for a better compressor because their actual ones produce too much hiss.
Although analog compressors add a little hiss to the signal because of their components (just like every other active device causes some hiss anyway), the more significant reason for the noise of a compressor arises from the way it is used.
How a compressor works
First, it makes sense to understand how a compressor works: The compressor limits the loud amplitudes and amplifies the soft tones.
By this, every hiss that has already produced by the interferences of single coil pickups, gets amplified too.
More specifically, after the compressor reduces the signal peaks, the entire signal (and by this also the hiss or noise) is boosted again.
Since the human hearing only perceives a mean volume and is unable to distinguish the peaks of the audio signal, the hiss seems to be even more intensive than it actually is.
If this signal passes several gain stages, like for example an overdrive or distortion pedal and, subsequently an – also amplifying- amp, the hiss grows steadily louder.
There is a decisive difference between a compressor and a gain stage that produces distortion is.
Although the hiss of a distort signal can be pretty intensive, it is in fact less perceivable since the distort parts are mostly quite loud and – of course – distort.
A compressor is typically used for clean parts and therefore the hiss becomes more prominent.
As soon as there will be hiss in the signal, it will be amplified by the compressor as well.
How to handle the hiss
Every compressor pedal amplifies the hiss that is produced by itself and other devices in its very own way.
The choice of the parts and the layout of the board matter.
And, one compressor produces a varying intensity of hiss depending on the room where it is used.
To minimize the hiss, you can take off the treble of your amplifier. This of course will darken the sound.
The only way to handle with the hiss of a compressor is, to wind down the volume when you stop playing.
During you play your guitar, the hiss will not be perceivable anyway.