DigDug2 questions

[ChRa]

Hi, I'm currently building a Baby-10 sequencer to go with my atari punk console. This got me thinking about out the DigDug2 project so that I could put it on my guitar pedalboard. I'd really like to be able to use this to get an arpeggiator or pitch sequencer effect. Is there a straightforward circuit that this could be paired with in order to get that effect?

Also, is it possible to get a CV out in addition to the optical output? Apologies if this is a dumb question, I'm still relatively new to the game and I really don't know much about synthy stuff.

Thanks!

[BrianS]

There are two forum guys (AlanP and peAk) that do a lot of synth builds.  Alan in particular has posted several of his synth builds and is pretty freaking brilliant on this stuff.  Peak built a home studio recently which is totally awesome.  One of them should pop on and give you their opinion hopefully.

[alanp]

I's an iggerant meatworker.

But if you mean you're wanting to interface guitar pedals and eurorack synth modules, I'd suggest a Cat Girl Synth CGS60 "Stomp Box Adaptor" and an envelope follower.

I suspect that what you mean might also be a sample and hold circuit, not sure.

[ChRa]

Thanks for your responses. I'll be concrete--I'd love to be able to combine the existing wah/trem functionality of the DigDug2 but add the ability to do what this pedal does:
https://youtu.be/e6idBRbO7RU

Of course I could just buy that, but where's the fun in that? 

[ChRa]

One more thing I wasn't clear about--I want to use the pedal for a guitar input, not with a synthesizer (though if I could do both, great!).

[alanp]

Sounds like pitch-shifting to me -- that's a FV-1 job, possibly a custom program. Maybe Bean's "Mandroid" can do it, I'm rather shaky on just what that one does.

[WormBoy]

So, you want to change the pitch of the guitar, in a musical way ... a vibrato changes pitch, but generally not in a very large range (or it would sound bad as a vibrato). The Mandroid would not work as it only has fixed detuning steps that have to be selected with switches (and it is definitely not in tune across the fretboard). Something digital is probably your best bet here ... but that would likely not be straightforward.

The digdug has a sort of CV output already. It is meant to drive an LED, but it could also drive something else, I guess. You would only have to check how much voltage swing it puts out, and what the receiving end needs (so it might need some amplification and offset correction).

[ChRa]

Could you use the DigDug2 CV output that is meant to drive the LED to drive the expression input of the EHX Pitchfork maybe?

[WormBoy]

You would have to find out what kind of voltage the Pitchfork expects at the CV input, and what the Digdug is putting out. If they match closely enough, it is worth a shot (if you carefully mind polarity and the max allowable voltage for the Pitchfork on the CV input).

[MacHeath]

AFAIK the dig dug outputs 0 to 5 volt at the cv out, it's what I understood from the build doc anyway. That's a pretty common value to interface with external modules. Was planning to try it out once I build the dig dug, on my ehx memoryboy dlx for example. Will be interesting to see how you manage.