The CheapComp - Compressor kit

The pedal works great. It’s really good for the price

Daniel D., 22.05.2020

I got this pedal mainly because I thought the principle was really cool: LEDs driven by the instrument signal varying the value of a photo-resistor which in turn modulates an op-amp gain ! Really neat and simple, with very few components.
I built the bass version of the pedal using the higher capacitor values supplied. Its worth noting that the kit didnt include the bass value for C4 (4.7uF), so I first used the standard 2.2uF but felt too much of a bass drop, so put in a big 10uF instead.

I tested the pedal on guitar first: on full sustain the sound is great, lovely definition and natural sustain. On lower sustain settings however, I felt the compression would let the attacks through and squash the remaining part quite harshly, sometimes with a little fuzziness especially when playing chords. Letting the attack through and compressing the rest is a feature of the design, due to the response time of the LED/photoresistor combo (found this on the forums). So, based on the bass circuit used on guitar, I would have given 4 stars as I found one great set and forget setting but found lower sustain settings a bit strange... this is probably due to the circuit letting too much bass in for a nice guitar comp so I tried it on bass.

Used with a 5 string bass tuned to low A the compression is FANTASTIC! The same lovely plump tones with sustain all the way up, and great punchy attacks when the sustain is rolled down, really gives the instrument some bite without any noticeable change in tone. With the 10uF cap on C4 I can hear no loss in the very low frequencies. A little added hiss on low sustain settings, but thats to be expected in compressors.

Definitely a 5 star for bass, and because the principle of the circuit is really cool if youre interested in knowing how this kind of stuff works! Ill be building a second one with guitar values to see if it is better suited for guitar.

James L., 18.12.2020

Facile à monter, je l’utilise assez souvent. Il donne du punch et de le clarté au son sans trop forcer la dose.
Bon produit, merci musikding.

Christophe B., 29.10.2021

Ive already tried and made a few compressors and this one is the best Ive built so far, and the cheapest. And definitely suitable for bass guitar. Sounds great!

Erik B., 04.05.2023