Rochambeau Musical Apparatus Dirty Doper

[Dandolin]

Yarp-the green or blue painter's mask especially goes light on fragile finishes but prevents scrapes and lift just fine ; stuff is a wonder.

I am so excited to see this progress!

Also:

[univalve]

Any news?

[crochambeau]

The first two units are shipping today, I'm wary about broadcasting my intentions in regards to how many I can ship per day (because I feel like it's been a string of me not meeting my expectations), but at this point it's a pretty aggressive schedule and I'm optimistic...

I'll have more pics soon (once the bottom plates are actually screwed into place)

[DannDubbleEwe]

Hot diggity damn!

[resincum]

right. i'm stoked

[UglyCasanova]

Take your time, dude. These are looking more and more insane!

[lordgalvar]

Looking awesome...gonna be a blast exploring this thing.

[crochambeau]

Looking awesome...gonna be a blast exploring this thing.

Thanks! I expect yours to ship tomorrow - I also have a ton of keyed switches in my parts stores, I'll toss a key into the box as well (unless you'd like an entire switch assy?). There's maybe a 50% of it fitting your switch/enclosure, but I have plenty, so..

I'll shoot emails/PMs once individual units have gone into transit.



They do not sound *identical*, which from an engineering aspect is sort of a disappointment; but they both sound good and retain all the important characteristics. Here's to being hand built!

[D.o.S.]

Awwww yis!

[D.o.S.]

Also, while we're here, anyone want to explain CV to me?

[lordgalvar]

I don't know what it is going to do exactly in this device.

Simplest terms I can think of: Usually a variable DC voltage from 0-5v controlling an aspect of the device (some are different...synthmonger used 5-10v). The scaling and response to the voltage depends on the device (and why synths will say 1v/oct...)...think of an LFO as a variable power signal...0v is at its lowest valley, 5v is at the peak. If it controls something like a VCA 0v=no volume, 5v=full volume with a sweep inbetween.

To translate that LFO to an exp controller it will have to use the circuits output somewhere else (like an LED) and translate it to variable resistance (LDR) to make it passive.

EXP is just resistance and passive (not supplying power)...like a remote potentiometer.

[crochambeau]

You don't need to use/understand CV with this pedal, it's just available to exploit if you have other devices (like modular synths) that also use it.

With this circuit, the CV dictates the level of voltage supplied to the circuit, so it's like a remote control power starve. If you do not have anything plugged into the CV jack and turn the CV on, the pedal stops functioning, as it is fully starved....

You *can* feed a standard line level audio signal into the CV jacks, and the circuit will turn on and off with the signal (like a bastardized ring modulator) but getting a useful balance between the CV feed and something like a guitar on input is difficult. Also - there's a little bit of DC voltage on the CV jack, which may or may not negatively affect what is plugged into it.. I have had okay experience just plugging stuff into the CV jacks, but I sort of treat shit with impunity (as I usually have parts on hand to fix stuff I break)... so while I have done it, I don't exactly recommend the same (ie: I'm not responsible for others breaking shit).

A note about the CV - it's a VERY primitive circuit, and I've measured current draw that's a touch on the high side (100 mA @ around 10 volts, less at lower voltage levels) from a DC source supplying CV. I believe there are fixes applicable, but in the spirit of keeping my momentum I'm shooting that onto the future research shelf. If this current draw alarms anyone, let me know and I'll play around with it. Again, nothing is heating up, it's just that since I've already chased about forty rabbits on this circuit I feel okay with drawing a line in the sand.

[lordgalvar]

Interesting that the CV will take line signal! That is going to be awesome to play around with. Also got my frequency generator around too (and banana plugs)!

Excited!

[neonblack]

So the CV will work with a regular ol expression pedal right? So I can hit a note, let it ring out, and then drop the voltage with my expression pedal to screw with the note decay?

[crochambeau]

So the CV will work with a regular ol expression pedal right? So I can hit a note, let it ring out, and then drop the voltage with my expression pedal to screw with the note decay?

I forget if you opted in on the TRS 1/4" jack, but if so - yes, ring will send a buffered reference voltage and tip will receive in order to support standard (passive) expression pedals.

Another way to fuck with your decay will be to turn the instability pot clockwise, especially when the pedal is in feedback mode.

I'll include the coversheet to my build document which names the controls and should give a hint to what does what. It'll be some time before I get around to drafting a tips and tricks page, so if anyone wants to share their experience once they've had some time behind the wheel I'd love to hear it.