I have a fuzz face i built a long time ago. When it is plugged into my yamaha amp it has less highs and is very smooth sounding. When pluged into a buffered pedal like a ds-1 it sounds more tinny and crackly. This is because my amp probably has a lower input impedence than the ds-1. How can I buffer my fuzz face in order to get the same sound I have from plugging it directly into my amp and "load it down". Most the output buffers found on effects (many people have them on homemade tube screamers) have a high impedence and drive a low impedence line to the next effect or the amp. What I want to do is load down the output of the fuzz face to get that smoother sound, but still drive the low impedence line.
Any ideas?
- Nick
Um, change the volume pot to a smaller value? (e.g. 100k)
Bridging the output (500k) pot with a low value resistor (10k to 100k) will also load the output of the fuzzface. But as far as I'm aware, the effect you are describing is not a classic effect of low input impedance. Low impedance cuts bass, not treble in RC (resistive-capacitive) lines (tho my head is so fuzzy today that you should take this post with a grain of salt). fc (the half-power, or -3dB frequency) = 1/(2.pi.R.C). So extra impedance will lower the bass cutoff frequency.
A different situation exists in guitar pickups, where a high impedance load is needed for maintaining high frequencies. Pickups are inductive sources (but the fuzzface shouldn't present any significant inductance unless you are using a very long, coiled cable).
I hope this helps somehow.
Almost forgot. An easy way to trim highs from a ff or any other pedal is to put a simple high pass filter to ground near the output. In the case of a ff, a 10kA pot in series with a 0.022uF capacitor works very well. Connect these between the signal line going to the volume pot (e.g. lug 3 of the volume pot) and ground (e.g. lug 1 of the volume pot). This mod is also described in the Simple mods section of diystompboxes.com
So I guess I'll try putting in a 100k volume pot in place of the 500k pot I have in it now (i think it's 500k if not it's 1meg). I should put a standard buffer after that too, that should keep the sound from changing when I plug it into different things. I need to figure out how to get away with soldering in a college dormroom, maybe I'll make a workbench in front of the window with a fan, that should do it...