# Another Hydra delay (with a tweak)



## Boba7 (Apr 11, 2020)

Hey,

So I just finished my Hydra delay. It sounds glorious. 
I used A10k for the mix pot, and B50k for feedback (see below)

I wasn't satisfied with the fact that with only one head selected there was not much feedback available. And when two heads were active, the oscillation could become way too loud. 
So I built a simple Electra circuit that I put in the feedback path. I used the values from the Lovepedal JTM but with 1N4001 for clipping diodes. 
That allows me to push one head into oscillation, but also to limit the signal and add some slight grit when pushed. It also cuts bass a little in the feedback path, which I prefer (I love the darker positions, with the Age pot well engaged. Now it doesn't get muddy even with a lot of feedback).
All in all, it gives a slightly warmer and more "analog" feel to the repeats, which I really like. 

I went for the classic look, inspired by other builds I saw here.

Thanks for nice PCB, programming, and for the cool faceplate too @PedalPCB !

Cheers


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## prairiestate (Apr 11, 2020)

This is really cool. Interesting how you found a solution
I haven't looked at the schematic, but are FV-1 delay circuits something you can add a momentary oscillation (aka slam or feedback) switch to?


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## Boba7 (Apr 11, 2020)

prairiestate said:


> This is really cool. Interesting how you found a solution
> I haven't looked at the schematic, but are FV-1 delay circuits something you can add a momentary oscillation (aka slam or feedback) switch to?



In this case the feedback is analog, it’s not part of the programming, so yes, a slam switch would definitely be an option.
But with the various head configurations, the feedback pot always has to be adjusted, so it might not work out as well as you’d imagine


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## squarewavesurfer (May 9, 2022)

Can anyone comment on whether or not I am replicating what the OP is talking about in the attached schematic?

 Should the Electra distortion circuit be inserted before or after the C50k repeats pot?(edit-answer found, see below)  
I also added a DPDT switch to enabled/disable this mod.  Any help would be appreciated.


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## squarewavesurfer (May 9, 2022)

Boba7 said:


> Don't have the schematics with me, but I'll try to remember...
> There should be an opamp buffer after the FV1 output that goes more or less directly to the repeat pot. I just put the Electra circuit between the buffer and the pot. Can't remember why I chose the Lovepedal JTM values, probably because the layout was small
> I don't have the pedal anymore, but it sounded awesome!


Found the answer to my pre/post repeats pot questions from another thread.


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## Boba7 (May 10, 2022)

squarewavesurfer said:


> Found the answer to my pre/post repeats pot questions from another thread.


Hey! Sorry I didn't reply sooner, glad you found the answer


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## squarewavesurfer (Jun 2, 2022)

Was there a reason you chose B50k for the feedback pot instead of C50k?  Also did you use for your trimmer pot in the  distortion circuit?  I ask because I am finding I cant limit the distortion enough. Once I switch it on, the signal is heavily distorted and the B5k pot doesn't do much to lower it.  I followed the Pedalpcb Je'taime schematic and values exactly.


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## Boba7 (Jun 2, 2022)

squarewavesurfer said:


> Was there a reason you chose B50k for the feedback pot instead of C50k?  Also did you use for your trimmer pot in the  distortion circuit?  I ask because I am finding I cant limit the distortion enough. Once I switch it on, the signal is heavily distorted and the B5k pot doesn't do much to lower it.  I followed the Pedalpcb Je'taime schematic and values exactly.


Hey, sorry Im not gonna be very helpful, I can't remember what I did, and I didn't take notes. I think I based the electra circuit on the JTM from tagboard, don't know if it's the same schematic as the pedalpcb one.

Maybe try and change the diodes to diodes with a higher threshold, like 1N4148? you could also change the gain by altering some resistor values, but I don't know at the moment how to do it, I haven't been into electronics in the past months, and I tend to forget very quickly all the knowledge I gain when I'm into it haha!

Yes I found that B50k was better since the wet signal with the electra circuit was slightly hotter than the stock version


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## squarewavesurfer (Jun 4, 2022)

Thanks!  I figured out I made an error and connected the emitter to ground.  Once I fixed that, the bias potentiometer works great.


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