Here is an "MXR" envelope filter I got in for some mods.
Note that the parts are random, some carbon comp resistors, some film.
If you see a NOS MXR pedal, ask about the date codes, and try to get a picture of the inside to see if it's original.Here are the pots in this pedal, new ALPHA pots instead of original CTS pots.The original pots are the only way to date an MXR pedal, so this pedal is not very valuable even if someone could get it working, as the date codes and pots are gone. I have also seen these "NOS" pedals turn up with pots with the last digits as 0318 which means 2003 18th week.This is pleasing to the ear – we don’t want muddy sounding humbuckers, and we don’t want piercing single coil pickups, so, our pots help compensate and shape the tone right from the get-go.Also realize there are pots in the middle – we sell 300K pots as well, which are slightly brighter than 250K pots.
Search for dating potentiometers:
By understanding potentiometers, or, “pots” (for brevity’s sake) a little more, you can make sure you pick the right pot for your guitar. By turning the pot, you are changing the way electricity flows through it.