EARTHQUAKER DEVICES: Grand Orbiter Phase Machine

The Grand Orbiter Phase Machine is a four-stage OTA phaser, with options for vibrato or phasing (a bit like a Univibe).

Not exactly a small board, but not too much to take on either.  MLC caps might be a good idea for some of the 1uf caps to save space. 

Currently unverified.  I have reviewed the schematic a couple of times, and two errors have been found and corrected, but still...  it's a huge board.  What could go wrong, right?

EARTHQUAKER DEVICES GRAND ORBITER PHASE MACHINE - VERO LAYOUT

KORG: MS-20 Filter, Tim Escobedo Version

If the other MS-20 filter is all too much, maybe this will be easier.  It's Tim Escobedo's adaptation of an MS-20 style filter for guitar, just using the an LM13700 and running at 9v.  

KORG MS-20 FILTER - TIM ESCOBEDO VERSION - VERO LAYOUT

 

KORG: MS-20 Filter - Rene Schmitz Version

This is the Rene Schmitz version of the MS-20 Filter, which is used in the later models.  I didn't include the CV control inputs, as I have no plans on using CV.

KORG MS-20 FILTER - VERO LAYOUT

KORG MS-20 FILTER - BUILD REPORT

This is a very particular sound, and while it doesn't have a lot of uses, it does do a screaming filter sound really well, and can go into oscillation.  It would be more useful with the frequency control running off an expression pedal - or in a synthesiser where it belongs...   

I would firmly recommend adding a volume control at the end, as this can really pump out some level, and/or do not place it in front of anything that is going to die if you feed it high input signal. 

Adding a single germanium diode to the pair of green LEDs or replacing a LED with germanium made a massive difference - I recommend trying this, as it tamed the beast somewhat.  Could pop it on a switch easily enough.  

I also added a 1uf on the input, as the original doesn't have a coupling cap, and I increased the output cap from 470n to 1uf, just because that's what I had on the input.  I have large 1uf caps on the layout, but I decided to use multi-layer ceramics to keep the size down.   The layout is quite flat, basically nothing is higher than the ICs.

Voltages are running at around +/- 17v instead of +/- 15v as that's the best I could do with the MAX1044.  I didn't exactly put in a lot of time trying either.

Note:  diodes and a 10k resistor are on the breadboard 

MUSITRONICS: Mu-Tron Micro V

The Musitronics Mu-Tron Micro V is a cool old auto-wah / envelope filter from the seventies - I feel I need to be wearing a valour tracksuit, possibly with a half-unzipped jacket exposing generous chest hair with a gold dangler to really play this properly.  Maybe a moustache too...   

I've used a LM13700 instead of the near impossible to find CA3080 (real ones that is).  In the thread on DIY Stompboxes there's a reference to changing the 1M resistor on the collector of Q2 to 470k / 500k for a better sweep (I have not tested this yet).

If you're interested in how envelope filters work and have some spare time to read and wrap your head around this, here's an excellent reference by Mark Hammer.

MU-TRON MICRO V  - VERO LAYOUT

This one is verified.  Note the two sides of the LM13700 are tied together.  I'm yet to test them being split.  In the thread, they say that it just sounds a bit sweeter with both sides running together, so I'll probably leave it that way.

It did take some filing to make it fit, but I did manage to fit it in a smaller than planned enclosure.

ORIGINAL SCHEMATIC 

VIDEO DEMO

RECKLESS: Pellucid Compressor

The Pellucid Compressor by Jonny Reckless on DIY Stompboxes

RECKLESS PELLUCID COMPRESSOR - VERO LAYOUT

note:  if you see an older layout of this from me - don't use it; I uploaded a working file with a mistake and now can't edit the thread on DIY stompboxes.

ON THE BENCH