EHX English Muff'n with treble taming mods
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- Опубліковано 13 жов 2024
- So the main complaint on these pedals is that there's way too much fizzy treble, but with a few choice capacitor changes there's a beautiful preamp / overdrive pedal in there!
There are a nice variety of tones on tap here, from a very light grit to a fuzzy tube-y muff sound. It can do something that's closer to a Marshall, but it's its own unique tone for sure.
The mods I did:
1. Replace C2 with a higher quality tone cap
2. Cut C6 to reduce treble content
3. Swap C10 with a 470pF to lower the treble tone control center point
4. Full re-cap of the electrolytics!
I also tried cutting C3 (another treble bleed part of the circuit) but that actually took away too much treble! With these 3 swaps the tone of the pedal opened up marvelously, as you can hear in the clip.
With a full electrolytic cap replacement, the noise floor is reduced even further and the overall tone tightens up a bit. Those things were like 30 years old, it was a long overdue fix!
2 years later update - I have bought ANOTHER one of these (pls help) and tried some other things to get an EVEN BETTER result. In a nutshell, there's SO much treble boosting in this circuit and there are 2 cold biased tube stages in a row. Along with a replacement of the large electrolytic caps, I tried this:
Remove C3 & C6 (treble peakers / voltage divider bypass)
Remove C5 (cathode bypass cap that's boosting HF on a gain stage) - This turns V1B into a slight cold clipping stage
Reduce R15 to 1.5K - changes V2A into a more evenly biased gain stage
Using 2 x 12AT7 tubes
I left the tone stack the same this time, but now ALL of the range on the treble is useable - with a dark tone, or a bright tone available. It starts to break up around noon on the gain knob, can do fairly clean and still has that fuzzy insanity at the top of the gain stage.
It's like adding a whole new Marshall / Hi-Watt channel to my amp! I'll make a video showing this at some point.
Como haces para tener esos tonos? En el mio, los agudos estorban demasiado... Y toco con single coil.. a pesar de que le saco los agudos, no puedo encontrar el seteo justo.
Las modificaciones están en la descripción. Requiere un poco de trabajo en el circuito - cambiando algunas partes obtendrá estos sonidos.
Gee, saying what the mods Actually WERE would be nice. “Clipped a few capacitors, changed a few values..” I guess you’ll keep that info as secret as the recipe to Coca Cola.
OK let's get technical!
+ I replaced all the electrolytic caps with higher voltage components. You can also up the main electrolytic values if you want a stiffer response. (C13, C15, C16, C17, C18) .
+ The cathode bypass caps (smaller electrolytics near the tubes: C1, C5, C7, C9) can also be changed, but that will also change the gain and frequency response of each tube gain stage.
+ I used some higher quality capacitors at key tone locations in the circuit (C2, C4). You could change the values too if you want looser bass response (bigger = more bass).
+ The main issue with these pedals is the god-awful stock treble, and there are a few points in the circuit where there are treble bleed capacitors (C3, C6). Cutting one or both of those out brings the treble down nicely. You can also modify the tone stack to make it more Fendery or more Marshally. I changed C10 to 470pF instead of 220pF to lower the center frequency of the treble knob. If you want a more classic Marshall stack, change C11 to 22nF, (so it matches C12).
Thanks man, I’m gonna try this.
Excellent. Thank you!
Cut out the C3 and C6 caps and jumped it: what a difference! The treble knob is useable again. Way more cream, less harshness.
Already did the C10 and C12 mod with the values you suggested: made the EQ a bit less ‘responsive’ as a whole, but absolutely more useable in tone: more focus, less highs.
Final technical geek question: would changing C4 to 0.047uF or even 0.068uF give me more bass?