Recent content by thunderaxe

did you consider replacing the 3x series 4148s with LEDs? the keeley rotten apple (pedalPCB sour grape) did that, being an adaptation of the op amp big muff (pedalpcb dream fuzz). the LEDs would have about the same Vf but maybe a different curve and tone.

TEACH US YOUR WAYS

the marshall bluesbreaker/guv'nor circuits have a very clever way of controlling the gain of two cascading gain sections via a single-gang pot but it requires the second stage to be inverting with its gain controlled by a variable input resistor, and i think it would be way too much to convert...

with the values the way they are now, it would require a dual-gang pot. i was talking about what it would take to make them the same value so you don't need a special pot. i feel like the drive section could use more gain, so i would maybe up that to 10K. and then in order to get the first gain...

unfortunately for me i know even less about cars than i did about guitar pedals when i first asked this question. fortunately, i have learned a lot more about guitar pedals in the year and a half since. so here's what i understand about the circuit and you can let me know if i get anything...

a pot sweeps lug 2 (the wiper) from lug 1 (far left, CCW) to lug 3 (far right, CW).

do the MOSFETs produce noticeably more harmonics than the other clipping options? also, with the gain pot also being in the feedback loop, C13 interacts with it and really only comes into play in the highest gain settings, correct?

maybe it's just all the diode switching that's throwing me off, but what is the purpose of C13?

i would imagine that in a non-inverting soft-clipping stage like the tube screamer or the original dragon, while the clean signal is unity gain at the op-amp output regardless of the amount of distortion gain, still, the higher the gain, the higher the apparent volume, and thus the more the...

so by placing varying amounts of resistance in series with the clipping diodes, you are able to discourage the signal from getting clipped and thus to just pass to the output without clipping? that makes sense actually. why do you think peter went with non-inverting in the original design? is...

i'm curious what the reasoning was behind changing the clipping stage from non-inverting to inverting?

i think the 560R is just to put some series resistance between the op amp and the output jack when it's in bypass mode to protect the op amp.

...a hypothetical non-superbright simulation LED with a peak brightness at 10mA, i guess... multiply the resistor values by 10 to get a peak 1mA current

like so? https://tinyurl.com/25sytpmp

it bleeds off the bias current so that it goes to zero at the bottom of the sweep. i took the idea from the tremulus lune.