Octave Distortion Build.

[GuyCorbin2001]

Hi All, I'm a complete beginner in DIY Pedals, I have received my projects for university and one of the options is build a piece of hardware such as a pedal.
I had the idea of building my ideal Octave Distortion unit.
I'm wanting to incorporate a Polyphonic Octave Down which would feed into the distortion section.
the distortion section being a Dallas Rangemaster Style Treble boost into a Pro Co Rat style distortion, similar to Fuzzlord Effects Nazareth.
the key differences between my idea and the Fuzzlord Effects Nazareth is that the Nazareth uses a Green Ringer Style Octave Up while I was thinking of using an Octave down more similar to a Digitech Drop.
I'm allowed to use kits as a basis for this project provided I modify them or Frankenstein them together to make something unique.
any kits you recommend?
how will I get everything to run off of a 9v isolation power supply?
any advice for a beginner in general?

[ElectricDruid]

Welcome!

The first problem you're going to hit is that word "Polyphonic"! Traditional analog octave-down effects won't do polyphonic signals. For that, you need digital processing, and pretty sophisticated digital processing at that (this is not a job for the FV-1, for example). The Boss OC-3 seems to be the box of the moment for that, but I wouldn't want to try and build one.

Your only other option if you're keeping it analog would be to make your own hexaphonic pick-up (so you have a separate signal from each string). Then you can process the six strings separately, including octave down. But this becomes a somewhat different project. Still fun, but different.

Aside from that it's all very doable. Running off 9V is what pedal circuits expect to do, so most things are set up for that already.

Hope this helps,
Tom

[11-90-an]

Welcome to the forum...

For the most part, polyphonic octaving is hard to do with analog circuitry. The most it can do is track a single note (monophonic) and octave down that note. However, there are other options, all digital. I'm not sure but perhaps the FV-1 has an octave down patch?

if you wish to go with analog, you can try out Merlin's U-Boat, Colorsound Octivider, Shin Ei Octave Box, even the Boss OC-2

For the treble booster and rat it should be quite simple...

EDIT: whelp, Tom posted faster than me. Seems like FV-1 isn't cut out for this job...

[iainpunk]

the octave down is really hard to do analog
i was going to suggest the U-boat posted earlier, but i'm convinced that it can be done easier, somehow...

you could also include the MXR blue box's octave down, but only do one stage instead of two!

if you ring modulate the square wave octave down with the clean signal, you could end up with something similar to the u-boat! i don't know if that would be simpler tho.

cheers, Iain

[radio]

We still have this one as an easier option

https://www.diystompboxes.com/analogalchemy/sch/shocktave.html

[Mark Hammer]

any advice for a beginner in general?

Yes.  Start simple.
In that respect, it is hard to get much simpler than a Green Ringer, unless it is Gus Smalley's Octave-Up Sick Box - https://www.diystompboxes.com/smfforum/index.php?topic=69289.0 - or one of the various octave-up circuits from Tim Escobedo: http://www.jiggawoo.eclipse.co.uk/guitarhq/Circuitsnippets/snippets.html

The key element to keep in mind, in my own experience, is the sensitivity of the circuit, and match between what it is expecting, in order to do its job, and what the guitar signal path is providing.  Both octave-up and octave-down, in the analog domain, rest very much on what might be called "triggering".  So the input signal always needs to be above some minimum to make either type of circuit work well.

A second critical element is that both require an easily identifiable note fundamental, with most of the harmonic content removed.  Normally, that involves using the neck pickup, rolling back the guitar tone control, and picking above the 7th or even 9th fret.  Why the latter?  Because the short the string length, the less the harmonic content.

[GuyCorbin2001]

Wow, thanks for all the super insightful and quick responses, I should mention that my deadline is the 27th of April 2021 so about 12 weeks.
Is the any way of incorporating DSPs into an otherwise analog circuit to achieve a fully polyphonic octave similar to a Micro Pog or an OC-5 that's feasible for someone just starting out, if not then I'll just have to settle for monophonic octave down circuitry.
Again if you have any kits that you recommend i would love to hear, also if you know of people that make custom enclosures for builds such as this that would also be super helpful.
I'm in the U.K. if that helps for what brands or companies you recommend.

[GuyCorbin2001]

Here is the assessment brief description.

[Mark Hammer]

How comfortable are you with microcontrollers?

You should be able to score a Raspberry Pi Pico easily, and teach it to do something useful, like control patching or memorize mixer settings, etc.

[GuyCorbin2001]

I've never encountered them in terms of usage or building, I'm open to anything really.
Making a dirt pedal with an Octave Down element is just the first thing I had I mind since I want to replace what's currently on my board (a Micro POG into a BAT Coven.)

[GuyCorbin2001]

Could I possibly take an premade OC-5 or Digitech Drop and then just incorporate it into the by patching it into the Rangemaster -> Rat circuit?

[11-90-an]

Could I possibly take an premade OC-5 or Digitech Drop and then just incorporate it into the by patching it into the Rangemaster -> Rat circuit?

Yes. Probably second-hand ones... (for the price)

[Digital Larry]

I am wondering why you say the FV-1 cannot do octave down.  It does octave down via pitch shifting so it's polyphonic.  Witness verily:

https://soundclick.com/r/s7roov

[Radical CJ]

An easy build octave down that uses minimal components is the 8-Bitar design on the Parasit Studio website: https://www.parasitstudio.se/8bitar.html

However, as it produces a squarewave, having a distortion in front of it is sort of irrelevant except that the additional harmonics may interfere with triggering. 

[iainpunk]

I am wondering why you say the FV-1 cannot do octave down.  It does octave down via pitch shifting so it's polyphonic.  Witness verily:

https://soundclick.com/r/s7roov

i thought the VF1 only does up to 8 semitones up or down (4 per channel, put in series), meaning you need 2 of them to reach an octave, which is still quite feasible tho.

cheers, Iain

[antonis]

As Mark already mentioned, Gus Smalley's Octave-Up Sick Box is just a splendorous simplicity..

[ElectricDruid]

I am wondering why you say the FV-1 cannot do octave down.  It does octave down via pitch shifting so it's polyphonic.  Witness verily:

https://soundclick.com/r/s7roov

I suppose because I find the artefacts unbearable beyond even a few semitones. I've mentally ruled it out.

So I take it back; it can do an octave down (or up, come to that). Taste varies and some people may find it acceptable for their purposes. In the context of the OP's original question, it might be quite suitable, since it *would* be entirely DIY and much more in the spirit of the project.

PS: That sound sample you posted doesn't sound half bad (that's high praise, considering how I feel about the FV1's pitch shift). The filter effect helps hide the worse of the warble and that weird plasticky quality that it gets.

[iainpunk]

PS: That sound sample you posted doesn't sound half bad (that's high praise, considering how I feel about the FV1's pitch shift). The filter effect helps hide the worse of the warble and that weird plasticky quality that it gets.

is there a pedal that just does that plasticky quality without the pitch shift?
for a song we recorded but never published, i put my pitch fork through a band mate's whammy, one oct up and one oct down, just to get that 'broken/fake' feel, that was the worst solo ever recorded tho, i used 100% WET reverb before a super fuzz and in to both the pitch shifters. i'd like to recreate that sound with less pedal board real-estate...

cheers, Iain

[Digital Larry]

PS: That sound sample you posted doesn't sound half bad (that's high praise, considering how I feel about the FV1's pitch shift). The filter effect helps hide the worse of the warble and that weird plasticky quality that it gets.

Well, I know what you mean, FV-1 pitch shift up is pretty bad.  The sample I posted is (I think) dry with octave with and without filter.  Don't exactly remember!  I think for the purposes of the OPs project it's acceptable.

.... that was the worst solo ever recorded tho,

That sounds like a challenge to me!

[ElectricDruid]

is there a pedal that just does that plasticky quality without the pitch shift?
for a song we recorded but never published, i put my pitch fork through a band mate's whammy, one oct up and one oct down, just to get that 'broken/fake' feel, that was the worst solo ever recorded tho, i used 100% WET reverb before a super fuzz and in to both the pitch shifters. i'd like to recreate that sound with less pedal board real-estate...

That ought to be possible on an FV-1. You could use the left input/left out for one octave up, and the right side for one octave down, and then feed one into the other! Hey Presto! Hideously munged frankensignal bearing only a passing resemblance to a guitar!