The Tectonic Compressor gives you easy to use, transparent compression that works well with single coil and lower output humbucker guitars. Based on a compression unit from the 70’s, it is an “opto-compressor” because of its use of an optocoupler in the circuit.
If you are new to guitar effects, you may be asking yourself, “What does a compressor do?” The simple way to think of it is that it basically tries to make all of the frequencies in your signal the same volume level, or in other words it “compresses” the frequencies into a certain range. So, if the low frequencies are not very loud, it raises the volume of those to where you want and if the high frequencies are too loud, it squishes them down to be even with the lows. The other effect of the compressor is that when it makes all of the frequencies the same level, it tries to keep them at that level as long as it can, which gives the effect of your note lasting longer or “sustaining”. Hence you see many compressors with a “Sustain” control on them. This is basically the intensity of the compressor effect. Turn it down and you get a little compression and a little more sustain of your notes, turn it up and you get more volume, more sustain, and a really squashed sound. Some compressors have several controls that can control the attack, release, and ratio of the compression as well. A normal good starting point with a compressor is just volume and sustain knobs at noon.
So to smooth out your sound and get better sustain for lead work without much effect on the tone of your guitar, a good compressor is the way to go.