question about CV / DIY Sequencer

[propel]

Hey everyone,

I have recently been looking into the world of DIY synths and came accross this:

http://www.synthrotek.com/2010/09/03/8- ... -full-kit/

And it got me thinking about CV inputs and all and I was wondering: would this be compatible with any synth that can use CV? Say I was to build this, could I use it with any synth with CV capabilities, or could I risk doing damage to the synth? Also, just out of curiosity, I was wondering what you guys thought about the kit; does it look legit and all.

Thanks for the help!

David

[space6oy]

depends on the CV format. CV/gate, Hz/V, V/octave, some info on those here:
http://www.vintagesynth.com/resources/glossary.php

[Solderman]

Thanks for pointing this out, I might try it!

[propel]

Thanks for the replies, that glossary looks like essential reading and I'll dive into to it after work.

But, just to be on the safe side, if I was to use that sequencer with a Synth that takes CV, is there potential to damage it if I do a shody job building the sequencer? I ask beacuse it would be the first time I build one and don't want to explode some nice gear.

Thanks!

[atkbg]

That looks an awful lot like the baby 10
http://www.midiwall.com/gear/babyseq/

[space6oy]

That looks an awful lot like the baby 10
http://www.midiwall.com/gear/babyseq/

wow, know what that was published in?

Make it look nice, you will be glad you did when something f**k up and you have to try and troubleshoot it.

[nathanscribe]

OK, so first up, both V/Oct and Hz/V are DC. Neither of those protocols use AC voltage, they are different systems of interpreting DC, for want of a better expression. I've had wine. Forgive me a little sloppiness. As long as the sequencer ouputs a positive voltage (mabe up to 5V or more) then you can get a useful CV from it. Gate triggering is another issue, and there are three systems commonly used - positive triggering (0V is off, positive is on), short to ground (aka S-Trig, where 0V is on and positive means no short so effectively off), or Yamaha's version which is above a certain voltage for off, below another for on (I forget the values, it's sometimes compatible with S-trig, but not always, depends on the kit).

So, make sure you know the CV and the gate type. Other than that, it looks like about a simple sequencer as can be made. If you build it, they will come. Or something.

[Stab Frenzy]

Actually it doesn't matter if the synth is V/Oct or Hz/V for a sequencer like this, as it's not quantised anyway. You'll get a more even spread of frequencies if the pots you use match up to the scale the synth has, but either way will work fine.

There's always a chance you can make something so badly that it'll destroy a synth, like if you somehow got mains voltage on a CV output, but if you can follow basic assembly instructions you won't build it in a way that can damage the synth. CV inputs are usually pretty hardy.

[propel]

Thanks Stab Frenzy, that's exactly what I wanted to know.

I think I'm going to order it along with the APC on their site, fun project to keep me busy this summer