Pedal Box Shruthi?

Has anyone ever mounted a Shruthi into a metal enclosure like a guitar pedal?

Shruthi seems about the same size as the medium guitar pedal boxes (I am thinking aluminum) and could even have a “bypass” switch as a power switch.

Does anyone see anything wrong with this (apart from having to open a lot of button holes!)?

Also, has anyone ever tried to “adapt” a shruthi to do anything with a guitar or other instrument? Maybe the Sidekick was better suited, but still any opinions on this?

There has been a start to a discussion regarding this, sort of, in the ladder filter thread. I built two ladder filter cards, one for a Shruthi and one to use as an effects box I hope. The only issue I have found with the Shruthi is that you need to have a key pressed to get any sound, at least that is my understanding. The problem with using only the filter PCB is that, as far as I know, there is no modulation. I’m thinking maybe a few pedals hooked up to the filter, for cutoff and resonance at least, might help.

Interesting…I know the Shruthi needs a 2 second button press to initiate any sound filtering, but I am guessing that this could be just a software mod away? I have 0 programming knowledge, so I could not tell, just a wild guess.

It would be awesome if the software hack could be used together with a foot switch, so as to trigger this filtering when needed, and having a true-bypass when off.

That would be cool, the rest of the parameters could be pre-set, and have the “performance” page set-up with the 4 parameters you would choose. Combine with big fat knobs and you have a solid experimental pedal…

> I know the Shruthi needs a 2 second button press to initiate any sound filtering.

This is not correct. See presets 124…128.

Seems this was along the lines of the idea with the Sidekick, but surely you could use a full Shruthi the same way, just using standard stomp box bypass wiring. Not having used my Shruthi with a guitar yet, it might also benefit from impedence changing and/or preamp circuitry at the in and out if you are using it in a normal guitar pedal chain. I haven’t seen it done yet but you could also look around at what the modular and stomp box folks do to match input and output impedances. With the full Shruthi brain you of course get the mod matrix, LFOs, MIDI sync, presets…seems like it could be a great super filter. Seems like a great project for the Digital FX board too!

This would be great to make. I do not possess the tech know how to make something like this yet, but I would surely dive into something like this if somebody cared to point in the right direction.

Imagine Polivoks (has overdrive) and Yellow Magic with it´s delay…that would be cool, a sort of programmable super pedal…it could even have some sort of screen protection in the same way tube pedals protect the vacuum tubes.

I think that full Shruthi has the advantage of in a “pre-set and configure before playing” type of style which chimes better with typical pedal use.

Sidekick in that sense is more of a “performance” setup for tweaking knobs live, which is hard to do if put on the floor.

Couldn’t there be a normal shruthi with no env governing vca in the mod matrix and just have a bypass switch? And slap that bad boy in an Otter Box™ and go to town

Well as pichenettes pointed out the existing Shruthi can process external audio without triggering the VCA externally as it is. Just need to look at the aforementioned patches to see how to set everything up!


I was wondering what exactly was Pichenettes talking about (had no time to check my Shruthi).
It would be great if you could expand your explanation a bit further?

Does anyone think that impedance tweaks or pre-amp work needs to be done for the shruthi to be “guitar pedal class”?

> It would be great if you could expand your explanation a bit further?

If you want to keep the VCA open so that the sound always pass through the unit without being “gated” by the VCA, you just need to disconnect the “virtual patch cord” from the envelope generator to the VCA. This can be done in the mod matrix (scroll to env2 -> vca… set amount to 0). Once you do that, you won’t have to trigger a note for the sound to pass through.

This is what is used in patches 124…128.

I’ve been running all my software synths through the smr with that method to give a bit of that warmth

youll probably want some sort of fx send buffer pedal to shift/amplify the guitar signal to line level before going into the s1 too!

@herrprof: care to elaborate? Maybe a guitar booster pedal would work?

You cant hook a guitar directly into it, but if your amp has an fx send, use that!

Got it…mine currently doesnt have one, but I´ll look for one in friend´s setups.

Currently, I am planning on taking the Shruthi (polivoks or Yellow Magic) to “guitar pedal class”, so I was researching what needs to be done to have it comply with usual characteristics that guitar pedals have, be it the bypass switch, or the “set and use” interface.

I see there might be some impedance and or amplification/pre amp issues, but have no clue currently what exactly is different between Shruthi and most pedals.

I will find out though, have some friends locally that might care to pin point what and where. Will post any findings.

In the meantime, any info anybody has would be super-welcome.

It could be as simple as something like:

To get the guitar to line level. Something fun might be recasing the s1, the above project, and one of these:

And then add a bypass circuit to have it drop in and out of your amp:

What herrprof is talking about is along the same lines as what I was getting at. I agree that an amp with an FX loop would be the most graceful!

or you can just use any distortion pedal and crank the volume with no distortion. also, I’ve tried fender jaguar>cable>polivoks shruthi>another cable>marshall… I think that polivoks isn’t the best filter for filtering guitar because it has weird frequency range. I didn’t try yellow magic yet though. anyway let your ears decide.

If i may add a small notice…
I’m using my shruthis as external filters a lot, but i don’t know for whatever reason, simply powering the unit and directly setting the vca as open is not enough. In this case, the filter is, at best, half-opened, and whatever settings i use, i never have it completely open… Until i have the shruthi playing a not, or until i hit the test note. I have the version 0.97 on each of my units. I can’t remember the shruthi acting like this before. I tried to change the note - filter setting (i know that it’s hardwired), but this wouldn’t change anything. Anyone else have the same issue?

Oh, and I have used the polivoks shruthi as kind of a dirty wah pedal. You have to rise the volume a bit, the biggest issue being the impedance of your guitar signal. Search for a “clean booster”.