Mutable Gear RackMount Kits

Ladies and Gentleman,

lets be true: one little Mutable Box is fun, two of them even more but as they keep piling up the whole mess looks sometime more like the Gordian Knot and you can’t always rely on Alexander the Great coming around to help you when you need to replug something. So heres an escape - Rack Mount Conversion Kits for your favorite Gear:

Available from today are

  • Shruthi Euro Format Conversion Kit in Standard, 4 Pole Mission, Yellow Magic or Polivoks Flavor (28 TE Width)
  • Anushri Euro Format Conversion Kit (42 TE Witdh)
  • MIDIpal Euro Format Conversion Kit (20 TE Width)

All kits make your Mutable Instruments gear fit into an standard Eurorack Modular compatible 3HE Sub Rack.

The Shruthi-1 XTpro Kit seen on top is advertised in the Programmers Thread later this week

All kits contain the Faceplate, a Backplate where the new Jacks are mounted, 2 x 6.3mm Jacks for Audio, 2 x 5Pol DIN Jacks for MIDI and one 2.1mm Jack for Power, the needed Wires and all hardware to mount the bare PCBs (so also all stacking Spacers). For the Shruthi and Anushri Kits you may order additionally a Breakout Panel (8 TE) for the for easier access from the Front.

Shruthi and Anushri Kits have inputs every time on the top, all outputs on the bottom, so you can easily identify them even when grabbling behind the rack 25 second before your gig on a dark stage…

More Pictures are here

Im currently calculating the Prices, it will be a bit more than the Custom Cases due to the additional Jacks + Hardware, prices will be announced here asap. Subracks available on request.

Looks nice ! Yurrah

Pretty Smart

Looks good Frank. Perhaps motivation for me to join the dark side… I’ve resisted so far but all this talk of Euro rack, programmers, the Anushri,… the temptation is huge. I also have two sympleSEQ and a seqSQUARED to build and put somewhere…

Will a pre-built Shruthi or Anushri fit without de-soldering MIDI sockets etc?

point of no return, Frank :wink: you’ve started modular!

Ah I see from the photos now that no de-soldering is required.

Shruthis fit 100%, all you can see in the pics are preRack-Era and converted ( you can easily solder the audio wires to the PCB and the MIDI wires to the back of the MIDI Jack on the Digital Board).

For the Anushri you will have to trim the Power Switch a bit and remove the Audio jacks (which is easy cause you don’t need to poke the Solder from the Pads to solder something else). Otherwise the Anushri fits exactly by design.

For all your interest; as i don’t like aluminum colored Racks that much i asked for a quote for custom made black anodized 2x3 HE double Racks with Top, Bottom and Backplates… stay tuned.


Well… cool stuff. Now I feel like I really have to get some eurorack stuff… Will happen for me when I’m a bit less broke…

Could be clever to add 4 CV inputs, wired to the CV in expansion, no? With RtoR opamp buffers, (powered with the 5v rail provided by the shruthi) and maybe replace the CV inputs by pots when nothing is connected. Would yield a better integration of the shruthis in a modular environment, and make it even more useful. Especially since there’s room for such pots and input jacks…

Looks like they might be a bit deep for a Doepfer lc6/9 without at least some angled cables.

Pretty cool though

just a thought , but with the Anushri I can make mine fit as is in a 3 U subrack (with no lid) by putting bigger spacers between the boards and 4 more headers. If I am feeling ambitious and can find the crimpers I may make some cables so i can mount the synth board where I like , perhaps horizontally and hack holes at the back of the rack.

Theres next to no space for additional Jack on the Shruthi 19" Kit but i can well do a BreakoutPanel for you…

I don’t see how this approach will be able to fit many commercially available ‘eurorack’ cases - I have a bit more leeway than some in my setup but I don’t like to go deeper than 65mm behind the panel (I have quite a bit more depth available currently, but I’d like my modules to be able to fit most any case I might purchase for portable use)

I’d be looking to put all the I/O on the panel - and the shruthis can just tap the +12v available on the eurorack PSU? not a big deal to add a perfboard with a 2x5 header and just connect it to your typical eurorack busboard - extra points to do it as a chiclet and add some circuitry and pads for CV inputs/knobs and an adjustable clean gain stage to boost line levels to modular levels

I’m not familiar with this stuff at all, but if you move the shruthi slightly to the top, don’t you have a bit of room for a row of 3.5mm jacks? Probably not the potentiometers, but at least the CV inputs is quite cool.

It would make more sense to use the ±12v available supplies on the eurorack PSU and swap the lt1054, by the way. You can connect this PSU directly in place of the lt1054 socket.

Its absolutely no Problem providing a Breakout Panel with 3,mm Jacks for 4 CV out 2 CVin, Audio In/Out and MIDI In/Out. The Circuitry is up to you as i dont have a modular to test and not really burn to do a one off… When using a BreakOut Panel depth is less than cm. For the Power Id remove the LT1054 and wire ther ±12V directly to the 7x05 regulators Inputs.

Moving the Shruthi up to make reasonable space for the Jacks would force you to desolder the Audio Jacks - and i hear the folks screaming already…
Using the CVins without buffering instantly destroys the ATmega when the CV exceeds +5V or is lower than 0V.

@fleetway76 Think of Frank’s standard solution as a way of using a DIN subrack in a non-modular rack setup (with cables semi-permanently connected behind the panel, and plenty of space to do so) rather than a Eurorack modular.

For a standard Eurorack modular the configuration with front-panel breakout panel should give plenty of room for any MI product to fit into Doepfer cases.

Using the CVins without buffering instantly destroys the ATmega when the CV exceeds +5V or is lower than 0V.
I know this. Adding a little piece of epoxy with a (dil14) quad RtoR opamp is not going to eat much room though, I barely see the addition of a buffer as something problematic or difficult. Even for someone from the regulator swappers caste.

I’m not trying to criticize anything. That’s already lovely. I just can’t prevent myself from thinking that with relatively little effort, this could be pushed to the extent of something even better integrated into a modular environment. Which would attract even more people from the modular world to the shruthiversum™ (and provide you with moar potential customers… :D)

I would suggest instead a classic input stage with 2 inverters with unitary gain. First, this makes it easy to add more inputs and/or an “attenuverter”. Secondly, one can add caps across the op-amp I/O to smooth the CVs and avoid aliasing issues. The first op-amp can be powered by +/- 5V, the second by 0…5V. Finally, by actually looking at the datasheet, not all quad R2R op-amps have input protection.

Indeed. On my polivoks shruthi I’m going to add 4 CV inputs (and try it with the anushri!), I was thinking about a simple pot wired as a voltage divider to attenuate the CV signal, then fed into an asymmetrically supplied quad RtoR, but the double inverter thing totally makes sense. Thanks for the suggestion.
(it’s going to eat more room then, but nothing fancy I suppose…)

No wyou have 2 options: do it yourselves or just wait until i want to make my Shruthis fit to my Modular. Ooooops. Did i say Modular???