ProtoTypo PT6 – MCV4E

ProtoTypo PT6 is a straightforward conversion build of a Doepfer MCV4 into a eurorack module. I just removed the circuit board from original case, made a matching eurorack panel and gave that some fffuuuugly artwork! Not much to the build so I figured maybe I’ll just run through my magnificent paper sticker panel artwork method \:D/

Loose MCV4 circuit board with jacks removed plus the drilled 6hp eurorack panel. Drillwork looking almost not wonky, w00t?!

Read More…

ProtoTypo PT5 – BUD666

While working on my ProtoTypo PT3 build I came to realize that actually just about any piece of Behringer audio gear would likely make a pretty neat candidate for hacking. I suppose that Behringer brands mostly as sort of entry-level hardware for the budget conscious. That is, anyone looking to get into audio production will often choose the least expensive entry point and grow up from there.

This reflects on Behringer resale value too, as people looking to “step up” want to off-load their (older generation) hardware to a market that’s constantly flooded by Behringer with the next generation gear (often carrying similar price tag with older gen). Why this is great for hacking is, it puts a ton of ‘source materials’ up for grabs at a very low price. Hacking a second-hand Behringer, say, to even see if it works usually doesn’t set you back much.. Even if you end up destroying the device in the process. Just remember to sort & recycle proper!

Take something like the 5€ DJ mixer (VMX100) that I hacked PT3 from: You’d be happy to get even half of new knobs for the same price (VMX100 has 13), add to that everything else like jacks, PSU etc! Looking at it from the electronics side, say, a basic opamp summing mixer is a basic opamp summing mixer regardless of whether it rolls off a Behringer or Focusrite production line. Using a basic functional block like this in a some other context then simply boils down to identifying it with the help of schematics or a some reverse-engineering.

Anyway TL;DR, I’m almost getting carried away so let’s cut to the chase!

Some months ago I spotted this second-hand Behringer HM300 guitar distortion pedal selling for 15€. I couldn’t help thinking “Well that’s a bargain, wonder if this would make a neat Eurorack module?”, and bought the pedal just to have a look. And so we end up with this build post!

I give you ProtoTypo PT5 aka BUD666 aka BUdget Distortion 666 :D

Why the 666? Well although I didn’t end up adding any extra features to the electronics, I still figured my hack has to be at least 2.22 times better than HM300!

Read More…

ProtoTypo PT4 – Pairs

While working on my Monster Base (eurorack) case the thought occurred that maybe it would be nice to have some buses to route signals internally from one end of the case to the other, instead of running long patch cables (which can get messy in no time). And that’s this build, the ProtoTypo PT4 (models A and B) in all it’s simplicity.

For the panel artwork, the boring version would’ve been to use matching numbers on both panels. However I like my modular setup colorful, so I finished up the build with a twist on the Find The Pair / Memory game. Each of the bus pairs have similar images to label them:

PT4a panels

PT4a with cabling

PT4b single panel

PT4b with cabling, heat-shrink tubing missing.

Both units have about 4* 1 meter of shielded stereo cable between the modules. As you may (or may not) recall my Monster Base is 1 meter wide, so that’s where the figure for this build came from.

The set of cheapo christmasy paper stickers I had for the build didn’t all match exactly by colors, so I had to settle for the overall shape in the picture. The glue on these stickers wasn’t too great either so I applied a piece of packaging tape over the whole panel, neatly cutting the overlapping corners and wrapping it on the reverse side of a panel. This proved a very quick way to also protect the surface also from dirt and wear, so I think I’ll be using this method on later builds too. Unlike the awful white paint pen I used for ProtoTypo PT2, using regular marker on a paper sticker (or just laser-printing one) should produce way less drunkard looking panel designs :)

Material wise each of these units (set of two modules and cables) cost about 30€. Didn’t have enough old audio cables to cannibalize, matching phone jacks to recycle! The 4hp panels I cut from this 2*20*1000mm aluminium sheet stock I bought from hardware store.

As for the name of this build, hmm.. Pairs game.. Let’s call it PAssive Integrated Routing Solution!

In your face you boring, unimaginative “black text on matte aluminium”! :P

Eurorack Monster Base, design

Shortly after completing my TTSH build I started longing for some added functionality, as in having more function modules to patch sounds with. I then got into eurorack modular synthesizers, cobbled together a small desktop case (photo below) to house some modules in, and ran out of space shortly after. I have heard this is a very common story among modular synthesizer hobbyists ;)..

Oh well, looks like I’m about to design & build a bigger eurorack case!!

My first 3U 84hp eurorack skiff..

Read More…

TTSH, miscellaneous mods

I started putting together a build post about the electronics side of my TTSH, but there really isn’t actually much to write about that. It’s a kit, and they just work straight-out-the-box when you learn even the details before starting and keep soldering sessions at reasonable lengths (don’t rush the build!).

That said, building mine was probably the first time ever in the ~20 years of electronics hobbies, that I managed to install a resistor of wrong value, in this case to VCO2 triangle-to-sine wave shaper circuit.. Live and learn; had some D’OH moments doing a part-by-part trace of the entire circuit :)

Anyway I thought I’d bundle some of the simple mods under this post. All these three were suggested by user Nordcore in the various TTSH build threads the Muffwiggler forum. Read More…