Chuck D. Bones
Circuit Wizard
I used to hate BMP tone stacks too, until I figured out how to tune them to my liking.
I see an easy way to reduce the parts count by 2 without changing the sound.
Yes, I see your demo. Good one.
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- Thread starter steviejr92
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I used to hate BMP tone stacks too, until I figured out how to tune them to my liking.
I see an easy way to reduce the parts count by 2 without changing the sound.
Yes, I see your demo. Good one.
KR Sound
Well-known member
Nice! Is that like a Little Smokey with Tone?
BuddytheReow
Moderator
Hmm. My guess is take out R1 and R2? R2 was originally there to limit the current so I could add some hard clipping diodes without burning them out. Ask me how I know… The diodes didn’t do much to the sound so I took them out. R1 was more of a guess than anything else as an anti-pop resistor. The gain pot probably solves that now that I think about it.
BuddytheReow
Moderator
Kind of? I have a notebook of a bunch of things I’ve experimented with. The LM386 was pretty early on and forgot about since it was a one trick pony to my ears. A smoky amp is a bit different. This is pretty much a fully cranked chip driving the tone. That’s the cap going between pins 1 and 8.
Chuck D. Bones
Circuit Wizard
Depends on how you use it.
cdwillis
Well-known member
Ok, here is what I've got on the breadboard so far. Hopefully you can actually read the screenshotted schematic. Overall I think it sounds pretty good. I might adjust the Body and Treble controls a little more. The idea was to have the screaming sustain of a Governor/Crunchbox, but have an actually useable lower gain sound with adjustable thickness.
Chuck D. Bones
Circuit Wizard
Nice! What can you tell us about the IC & LEDs?
C4 is 47nF?
C4 is 47nF?
cdwillis
Well-known member
Yeah, I tried keep even the thickest setting on the body control above where it would mush out. The IC in it right now is a 1458d, because that's what I had handy at the moment. I'm thinking about changing the c3 10nf to 15n or 22nf to make the thinner setting a little less thin/harsh. I usually prefer the Rat low pass filter with a linear pot, so I'm going to try that too to see how I like the sweep.
cdwillis
Well-known member
Oh, and the LEDs are 3mm red ultrabright LEDs with the clear housing.
Chuck D. Bones
Circuit Wizard
Yeah, the stock Rat FILTER control goes up to 32KHz, no one is hearing the difference in the top octave or two.
Light Show!!!
A friend of mine asked me to build him a Red Llama, so I saw that as an opportunity to try and make some changes to the circuit.
First of all, I added a Jfet input stage that gives some gain (~14db if my spice model is in the ballpark) and drives a fairly standard Red Llama. Sw1 puts C3 in parallel with C2, for a large low end boost, that turns the pedal into a real fuzz (C3 and C2 values are still subject to change). At the end, a simple LP tone control.
Right now I have a CD4069 on the breadboard, and it's not super noisy but I want to try a CD4007 hoping it can make it quieter
First of all, I added a Jfet input stage that gives some gain (~14db if my spice model is in the ballpark) and drives a fairly standard Red Llama. Sw1 puts C3 in parallel with C2, for a large low end boost, that turns the pedal into a real fuzz (C3 and C2 values are still subject to change). At the end, a simple LP tone control.
Right now I have a CD4069 on the breadboard, and it's not super noisy but I want to try a CD4007 hoping it can make it quieter
BuddytheReow
Moderator
What does R4 do in relation to R5 and R6?
Chuck D. Bones
Circuit Wizard
R5 is so small that it doesn't do anything.
Chuck D. Bones
Circuit Wizard
Have you tried it without U$1 & R4?
Not yet! My guess is it will work just fine (drain load is pretty small)
cdwillis
Well-known member
Originally I thought once I turned up the pot all the way R4 100k wouldn't have anything in parallel with it and you'd have 100k directly between the pot and R6. So I put R5 100 ohms there to keep something in parallel with 100k. I later realized with the pot turned all the way up the signal has a direct path around the 100k so I don't really need R5.
I tried b100k for the low pass filter. Not sure it was better than the c100k. Then I changed 1k/3.3nf to 10k/2.2nf with the c100k pot and I like the sweep way better.
BuddytheReow
Moderator
Here's The Salamander mkII. I added an extra LM386 for more gain, swapped out the input pot for an A taper, and added some slight filtering. The input pot makes the circuit more responsive to my playing/signal. The extra 386 more than makes up for the lossy tone stack. Yea, it's loud. I'm much more happy with this than the mk.I
You know, during my practice sessions I actually sound pretty good. Once the "Record" button is pushed all of a sudden my playing ability is that of a 12 year old. I usually record these demos right after I get a tone I'm kinda happy with, so no warmups. Oh well.
Ignore that lucy blue jumper wire just lying there. It does nothing and I got lazy before snapping the pic.
You know, during my practice sessions I actually sound pretty good. Once the "Record" button is pushed all of a sudden my playing ability is that of a 12 year old. I usually record these demos right after I get a tone I'm kinda happy with, so no warmups. Oh well.
Ignore that lucy blue jumper wire just lying there. It does nothing and I got lazy before snapping the pic.
Chuck D. Bones
Circuit Wizard
You sure C1 & C2 are big enough?