Here's a guitar and bass compressor custom pedal I built by hand that is up for grabs. I build custom pedals for Dawes Audio out of SLC, Utah. It's based on the legendary Dyna Comp Compressor, but has been upgraded to 5 knobs and a bright switch to regain lost treble. It is the Engineer's Thumb Compressor by the amazing Valve Wizard! Here's some info on the compressor: "The Engineer's Thumb is a better compressor. It combines all the best features of the popular DIY compressors, without any of the sacrifices. It is built around an LM13700 Operational Transconductance Amplifier (OTA). This is functionally equivalent to the now-obsolete CA3080, which was famously used in the MXR Dynacomp (the Dynacomp works equally well with an LM13700, and it's half the price, so you will find it in some Dynacomp clones such as the Visual Sound Comp-66). Actually, the majority of guitar compressors currently on the market are Dynacomp clones. Just looking in my local music store at least five out of the thirteen compressors they offer are Dynacomp clones; everything from the Behringer DC9 (£20) to the BBE Bench Press (£144) (five of the others are optical compressors, one is digital, one is VCA and the other two I'm not sure about ). Therefore, when I set out to build a better compressor, I knew it had to be capable of matching the Dynacomp, but with some sort of advantage over it, otherwise there would be no point. As it turned out the Engineer's Thumb has almost every advantage over it; five times more headroom, about half the noise, and the capability for all five compressor controls! And, believe it or not, it also costs less and uses fewer parts!! A fully-featured compressor will offer controls for: Attack- The time it takes for the compression to kick in when a loud sound comes along. Release- The time it takes for the gain to recover after the loud sound has passed. Threshold- How big the input signal has to be before compression can happen. In most stompboxes -*including the Dynacomp- this will simply be labelled "compression" or "sustain" or something. Ratio- How much the gain reduces during compression. At the extreme we get limiting, where the output signal is maintained at a constant level no matter what the input level. This is exactly what you want for maximum sustain (incidentally, the Dynacomp is a limiter). Level/volume- You know what this does; compressing a signal makes it sound quieter, so you need some gain to bring the subjective level back to normal. In a compressor this may be called make-up gain. With the Engineer's Thumb you can adjust all these parameters very easily to suit your taste; in most cases only a single resistor needs to be changed (see schematic). Units offering all of these things are sometimes called 'five-knob' compressors. There are very, very few guitar pedals that offer all five; most have threshold and level only. A few also have attack (although more often than not it is actually a mis-named release control!). However, it is worth noting that there is little need for both threshold and ratio in a guitar compressor; the same sounds can usually be obtained with either. In terms of cost/performance ratio, the Dynacomp was an astonishingly good design for its era. However, it shows its age, and the main objection to it is its noise floor. This is because OTAs are fundamentally noisy beasts, and when the circuit is not amplifying a signal the OTA is just sitting there running at max gain, producing its maximum amount of output noise. An obvious solution is to place the OTA in the feedback loop of an opamp, so the situation is reversed. Now when the circuit gain is highest the OTA gain must be lowest (restricting the amount of feedback), so its noise is also lowest. This is exactly how the Engineer's Thumb works; the OTA acts like a current-controlled feedback resistor." This is a one of a kind pedal and has a custom graphic I designed with 3 green LEDs inside the triangle design. I think it sounds very musical and doesn't squash too much. You can also get some distortion out of it if you like. It works off standard Boss style 9V power, Onespot, Pedal Power etc. No battery power. This pedal is a new build and hasn't seen use other than me testing it. All hand built and soldered in USA. This pedal has great features such as: High Quality Stomp Switch 3 knobs for Volume, Tone, and Gain Hand built and soldered 9V DC power Rugged road worthy aluminum casing High Quality Components Custom computron futuristic design $110 Shipped Paypal Packed with care and will include a tracking number. This is a unique and awesome sounding pedal, get it before someone else does! PM with questions. Thanks for looking! You may also check out my other works on Tumblr and please like my Facebook- Dawes Audio SLC. PM me for a custom quote on a unique pedal of your design!