Hey all,

Hope this is the right sub for this. I'm trying to understand how dirt pedals work. Today, I kept the master on my ac30 very low and just turned up the pre-amp volume till the spot of break-up, and then added a booster to push it into overdriving more. Adding volume on the boost did not add overall volume, I felt, just dirt. Which sounds sensible from what I know. This is classic overdrive, at least in the pre-amp.

Now even with the master fairly low, this already came at a respectable volume (AC30s are crazy). However, it's still possible to have actual overdrive pedals which just give you overdriving sound at lower volumes, e.g. tube screamer, fuzzes, etc.

How do they do that? They do not seem to be overdriving the pre-amp with volume, it seems. Do they just alter the soundwaves such so that their shape is similar to that of what I created with a boost and volume, and still have it processed "cleanly" by the amp? Or how else do they achieve the actual overdrive? Would love to learn :-)