Harmonic Energizer clone

[soggybag]

...I looked at three schematics ...

Yet you did not read my one post.

Read the DC to ground on both ends of the cap ...

It is very easy to be mixed-up which end is which. That may be why we are wondering who is wrong. To ground with a clear notion which end is which *may* be the most comprehensible (or maybe not).

Let me give this another try. I'm measuring from the top of the board without removing any parts.

I put the black lead on the input jack sleeve which is connected to the ground plane on the PCB.

- At the junction of R12 and C9 my meter reads: 1.6v
- At pin 14 of the TL074 I get 4.6v

I made a second build using Mark Hammers idea to add clipping diodes. When I built this one I put C9 in reversed (to the schematic.) I thought I'd measure this one for fun.

- At the junction of R12 and C9 I get 0.05v
- At pin 14 of the TL074 I'm measuring 4.6v

Not sure what the comparison is worth, could it help clarify?

I tested both boxes and I hear a subtle difference in sound which could also be the diodes.

[antonis]

- At the junction of R12 and C9 my meter reads: 1.6v
- At pin 14 of the TL074 I get 4.6v

That's all you need for C9 orientation..

[PRR]

> - At the junction of R12 and C9 my meter reads: 1.6v
> - At pin 14 of the TL074 I get 4.6v

"+" to TLO74

> - At the junction of R12 and C9 I get 0.05v
> - At pin 14 of the TL074 I'm measuring 4.6v

"+" to TLO74

[soggybag]

Thanks again for the help. I built up another one of the boards and tried out Mark's suggestion of clipping diodes on the last op-amp. Sounds great!

I got these through PCBWay.com it's $5 for 10. I like prototyping this way better than strip board. Even though there was a mistake on the pcb if most of the parts are in the right place applying a fix is easier than it might be prototyping other ways.

To add the diodes I just soldered them across the pot legs. I still have 8 boards to work with.








The diodes sound great here. Placing the tone shaping before the clipping well worth exploring.

The gain and volume control need a little work. The clipping comes on about 9 o'clock. When the gain is above 9 o'clock you need to turn the volume way down.

I used a 500k pot (it's what I had on hand). Mark's suggestion was 250k.

[Mark Hammer]

Nice work!  Glad you like it.  Yep, either 250k or 500k is fine.  The goal is to have enough supplementary gain to make the diodes do something, without rendering the gain pot too "twitchy", in terms of being able to dial in what you want, and either of those pretty much nail it.