FIRST BUILD - Face Melter - SUCCESS

[Chuck D. Bones]

After you get the sockets installed, try a Red and a Green for some slightly asymmetrical clipping.

I'll go out on a limb here and assert that Q2 makes plenty of asymmetric clipping. Play with the LEDs if you like, but Q2 is doing all of the heavy lifting.

I can't believe (no wait, I totally can believe) all of the useless extra parts on that board. I'll breadboard it one day and if I like it, I'll suggest a Boneyard version. Here's a preview: the DC voltage on both sides of C23 is Vref. Jumper C23, delete R27. That's just the tip of the iceberg.

 

[Fizz]

I'll go out on a limb here and assert that Q2 makes plenty of asymmetric clipping. Play with the LEDs if you like, but Q2 is doing all of the heavy lifting.

I can't believe (no wait, I totally can believe) all of the useless extra parts on that board. I'll breadboard it one day and if I like it, I'll suggest a Boneyard version. Here's a preview: the DC voltage on both sides of C23 is Vref. Jumper C23, delete R27. That's just the tip of the iceberg.

Mr. Circuit Wizard, have you breadboarded this one yet? I'm getting ready to attempt it and was curious.

 

[spi]

C23? R27? Are we looking at the same circuit?

 

[Chuck D. Bones]

Mr. Circuit Wizard, have you breadboarded this one yet? I'm getting ready to attempt it and was curious.

One day... That circuit is way down on my list.

If you can't find CA3240, you can sub TL072.

C23? R27? Are we looking at the same circuit?

I was looking at the Build Doc dated 12.05.18.

In the current version, it's C8 & R11.

 

[Laundryroom David]

I can't believe (no wait, I totally can believe) all of the useless extra parts on that board.

There’s that half a dual op-amp doing sweet fuck all.

@Fizz I started working on this and then something else shiny distracted me. I had breadboarded it with a single op amp and tried a few I had on hand. Memory is thatvthe op amp had negligible effect on the overall sound if the circuit. I think I was even going to bug Chuck offline about how to make this circuit less … just less. Lol.

Anyway, it does sound good. Hmmmm. Maybe after I catch up on this stack of pcbs …

 

[Chuck D. Bones]

D2 serves no purpose.

The Q1 circuit is redundant because the opamp has an extremely high input impedance.

Why there are two Vrefs is anyone's guess.

If I was going to breadboard this, I'd replace IC1 with either a TL071 or a CA3140. I'd ditch Q1, D1, R2, R4, R11, C3, C8 R100, R101 & C102. Change R8 to 1M, R6 to 10K, C6 to 100pF and connect C1 to R6. Jumper C8. Bam! All of this is easily done on the PedalPCB board except switching IC1 to a single opamp. That requires a little trickery.

 

[HamishR]

Now I know why you call yourself Chuck. You like to chuck stuff out. I love it!

 

[Fizz]

D2 serves no purpose.

The Q1 circuit is redundant because the opamp has an extremely high input impedance.

Why there are two Vrefs is anyone's guess.

If I was going to breadboard this, I'd replace IC1 with either a TL071 or a CA3140. I'd ditch Q1, D1, R2, R4, R11, C3, C8 R100, R101 & C102. Change R8 to 1M, R6 to 10K, C6 to 100pF and connect C1 to R6. Jumper C8. Bam! All of this is easily done on the PedalPCB board except switching IC1 to a single opamp. That requires a little trickery.

I have everything I need to build this pedal except one 4m7 and one 2k4 resistor. I do have a 5M1 and 2K7. Could I sub these for those or would it mess up the build?

 

[Chuck D. Bones]

Those substitutions should be fine.

 

[Fizz]

One day... That circuit is way down on my list.

I don't know if this is any kind of motivation for you but I've recently been using this pedal in front of a clean amp. Now, this pedal is like a Marshall pre-amp in the switch up position. It does all flavors of Marshall in this position. And IMO with the switch in the down position, it is an SLO preamp. Previously I was using it more as an overdrive and distortion pedal but I much prefer it as a preamp into a clean amp.. though as an overdrive it did remind me of a really good SD-1 with way more tone control the way I was using it.

But, you've given us enough recommendations on this pedal for me to run with it and test these out. However, I'd love to hear your comments on the switch.