Author Topic: Works first time!...sorta-very trebly and a little noisy  (Read 6089 times)


Works first time!...sorta-very trebly and a little noisy
« on: May 26, 2010, 02:42:23 AM »
I gave this project a shot.  I've built a few BYOC's and GGG's from the kit and loved it.  I use those pedals constantly.  I have also tried a few diy breadboard projects like the beginner here, the small bear Tweak-O, an EHX LPB-1 mapped out from a GGG layout.  All those were off and I'm still working on them.  I turned to this one hoping a fresh start would help and it did.  I had full volume, even a great deal of boost.  Some really nice raunchy overdrive.  It is very trebly, I have to roll back my tone knob on the guitar quite a ways, but it still is a nice gritty biting tone.  Some of my capacitor values were a little off and I wonder if that is part of the problem.  I put two LED's and a 914 in the diode clipping section and it definitely has that punchy british in your face vibe.

I think I might try to locate the source of the treble and settle it down and take a stab at converting this into a stompbox.  The breadboard is sweet for experimenting!  Thanks for the tutorial, it was really helpful!


Re: Works first time!...sorta-very trebly and a little noisy
« Reply #1 on: May 27, 2010, 12:40:32 AM »
Increasing C1 from 0.01uF will let more bass into the circuit.

Increasing C3 will increase how much treble is filtered out in the feedback loops, which means treble frequencies will be less amplified. 25pF aims to mainly reduce radio frequencies. Higher will start into audible treble range.

I can't remember what effect C2 has, but I am pretty sure it affects the frequency response of the feedback loop as the gain pot is turned. Possibly creating a mid-hump with increased gain. Not really what you are looking for (I think).

C4 I believe would be the output cap, which at 4.7uF allows lots of frequencies through so I am not sure changing it would help.

C5 filters out treble frequencies to ground, which also limits how much high-end is distorted by the clipping diodes.

Soooooo increasing C1 gives you more bass, increasing C3 & C5 will give you less treble. The latter two would probably be your first targets.

At least that's what I have been led to believe. If I am wrong, someone please let me know!