Robaux 3PT

[J_Behan]

Toothpick and some white paint will sort that out

Yeah, I might give that a go. Some modes really need the pot position to be clearly visible. I asked Exploding Shed about it and they said Robaux was calling it the 'black knob edition'. Maybe I'll hold off for a while and see if I just get used to it.

I do like the module though. It's not as deep as an O&C obviously, but it's more hands on and fun to play. It would make a great addition to a small/live case especially.

[bommelito]

I've been searching for some technical specs, especially for LFO mode, but couldn't find anything.
Can someone provide these data

- LFO range
- multiplication factors

The wave shapes seem to morph like this (CW to CCW): sine - triangle - saw - rect.

Thanks!

[mrhooks]

This module looks fantastic! It seems easy enough to use that one might not even need to consult the manual. I'm not a fan of PCB panels, but I guess it's the only way to get the cool lights. Robaux's Instagram makes it sound like pre-built modules will be released only for a short run. If so, I hope I am ready to buy one when they become available, or that other people will build and (re)sell them.

One thing that maybe could be better is it could have the main knob control something in every mode. Currently, only two of the seven modes even use it. Either move an important function from one of the small knobs to the main knob (such as root note in chord progression mode) to free up a small knob for an additional function (maybe add inversions to chord progression mode), or if possible, find some creative way to use it to control probability/variation in some of the other modes.

[aragorn23]

I can't get it to go higher than 4.8-ish volts, not 5. The trimmers on the back all go to max and the three top trimmers on the from are only used to calibrate right?

Did you ever figure this out? I'm also struggling to tune the first two channels because the back trimmers can't quite reach 5V...

[Airell]

I can't get it to go higher than 4.8-ish volts, not 5. The trimmers on the back all go to max and the three top trimmers on the from are only used to calibrate right?

Did you ever figure this out? I'm also struggling to tune the first two channels because the back trimmers can't quite reach 5V...

No, I'm sorry... I just learned to live with it... :(

[aragorn23]

I can't get it to go higher than 4.8-ish volts, not 5. The trimmers on the back all go to max and the three top trimmers on the from are only used to calibrate right?

Did you ever figure this out? I'm also struggling to tune the first two channels because the back trimmers can't quite reach 5V...

No, I'm sorry... I just learned to live with it... :(

After chatting to the module designer I realised that the instructions for calibration are actually slightly ambiguous - I was trying to calibrate using the trimpots on the back of the module and you're supposed to use the actual pots on the front

[Airell]

After chatting to the module designer I realised that the instructions for calibration are actually slightly ambiguous - I was trying to calibrate using the trimpots on the back of the module and you're supposed to use the actual pots on the front

Even then... for me I can't calibrate it higher than 4.8v.
Pots on the back all the way max and tuning with the knobs at the front.

Did you work it out?

[aragorn23]

After chatting to the module designer I realised that the instructions for calibration are actually slightly ambiguous - I was trying to calibrate using the trimpots on the back of the module and you're supposed to use the actual pots on the front

Even then... for me I can't calibrate it higher than 4.8v.
Pots on the back all the way max and tuning with the knobs at the front.

Did you work it out?

Yeah, I couldn't get it higher than 4.8v either, so I just programmed it with a 4 octave range instead of 5.

[MARK27]

For me, I think I would be really into this module if the UI was built around a long throw fader instead of a knob. I bet you could design a fader version in the same hp (or very close). It would just have a slightly different layout. Of course, this is totally just personal preference, but I really do love the idea of controllers with more visual feedback. I could totally imagine like a bank of eight faders that just had single led indicators to display the CV modulated value.

[Airell]

Yeah, I couldn't get it higher than 4.8v either, so I just programmed it with a 4 octave range instead of 5.

That's true. The calibration instructions also do not go higher than 4 octaves (calibration done via a VCO and looking at the Hz).
But because the manual/specs said it's 0 to 5v, that would imply 5 octaves. When this could not be done with the 3PT, the specs should be changed...

[Bubbles]

Anyone find this module in the US yet? Either assembled or DIY?

[Bubbles]

Just heard from Synthcube:
“Yes, we have an order in with Robaux and look forward to having them in the store!”

[Thonk Support]

We have a full Robaux restock at Thonk this week too

[chiefthomson]

just built the module last weekend. the main reason I wanted it, is to build nice chords.
Something I don't understand, the manual apparently neither, what does compress do when in Chord mode?
Does anyone know?

I tried to figure out what and how it does it but I don't get it. Hope someone could explain.
The manual only states "... For each channel you can set whether the notes are quantized within an octave. ..."
the reason why this kinda doesn't make sense, if you have everything in the init position, the module is by default outputing a major chord, without offset or anything...

thanks.

[mrhooks]

Something I don't understand, the manual apparently neither, what does compress do when in Chord mode?

I don't own the module, but if I had to venture a guess from reading the manual, since the Variation trim pot affects all the notes at once, maybe the Compress trim pots allow you to "undo" the spread for individual notes?

I'm probably incorrect, but as you said, the manual is unclear.

[chiefthomson]

Something I don't understand, the manual apparently neither, what does compress do when in Chord mode?

I don't own the module, but if I had to venture a guess from reading the manual, since the Variation trim pot affects all the notes at once, maybe the Compress trim pots allow you to "undo" the spread for individual notes?

I'm probably incorrect, but as you said, the manual is unclear.

I got an answer meanwhile from Robaux via Facebook, if anyone else is looking for more info.

The 7 chords he mentions in the manual are the standard chords major/minor chords I,ii,iii,IV,V,vi,vii°, so nothing fancy there.
Compress is only an on/off function, after a certain threshold it activates, so fully ccw it's off and fully cw is on. What is does, is simply enforcing the note change to only happen within an octave, from what I observed, always the lowest octave the modules outputs.

My rack is tuned to F minor...
The variation has 4 modes, the first one is the standard triad, eg F minor (F-Ab-C). The variations only affect the 2nd and 3rd output, trying to imitate bigger chords with 3 notes I think.
2nd mode (around 10 o'clock) gives you F-Ab-E (I guess a 7th)
3rd mode (around 2 o'clock) gives you F-B-G (I guess a 9th)
4th mode (around 5 o'clock) gives you F-Db-A (I guess an 11th)

Some other things not mentioned in the manual:
- the CV input only accepts the white keys for transposing notes and the knob becomes dead once you plugin a cv input.
- the root note knob is increasing notes by semitones, so does the offset button, but with a max of 11 semitones, so you can't offset by an octave unfortuantely
- something I didn't realise straight away, when in chord mode and all buttons are set to init fully ccw, the module already builds a triad by default, so the LEDs won't align at the very left so init ccw would be a C Major chord CEG. This means you can directly take the 3 outputs, plug them in and tune your OSC accordingly.

[mrhooks]

Cool, that's essentially what I thought, although I didn't realize the Variation trim pot actually changes the notes that way - I thought it just transposed the same notes by octaves (F-Ab-E would become F-E-Ab, etc.). They should have explained that (and a lot of other things) in the manual. I wonder how they chose the notes?

BTW, you could say F-B-G is an F add 9 add #11 with no 3rd, and F-Db-A is an F Maj with a b13. But it would be much easier to abandon the F=root idea and say they are a G7 in 3rd inversion, and a Db Aug in 1st inversion, respectively. F-Ab-E is an F min/Maj7.

[chiefthomson]

Cool, that's essentially what I thought, although I didn't realize the Variation trim pot actually changes the notes that way - I thought it just transposed the same notes by octaves (F-Ab-E would become F-E-Ab, etc.). They should have explained that (and a lot of other things) in the manual. I wonder how they chose the notes?

BTW, you could say F-B-G is an F add 9 add #11 with no 3rd, and F-Db-A is an F Maj with a b13. But it would be much easier to abandon the F=root idea and say they are a G7 in 3rd inversion, and a Db Aug in 1st inversion, respectively. F-Ab-E is an F min/Maj7.

I wonder too on what logic this is based off, he was a bit vague in technical/musical terms, the note changes I was testing myself to figure it out.

thanks for correcting the chords, as you can tell, not my strong skill

[mrhooks]

No worries. I also realized F-Db-A could be F Aug, if you call Db C# instead.

And if you also call F E# instead, it could also be A Aug. I forgot that Aug chords are like dim7 chords in that way.

[chiefthomson]

No worries. I also realized F-Db-A could be F Aug, if you call Db C# instead.

If you wanna have a listen, did a quick vid with the Robaux 3PT

[Ebotronix]

here's the 3PT a scale list!

# Bank 1
1. Chromatic in cent 0,100,200,300,400,500,600,700,800,900,1000,1100
2. Major Pentatonic 0,200,400,700,900
3. Minor Pentatonic 0,300,500,700,1000
4. Major Blues 0,300,400,700,900,1000
5. Minor Blues 0,300,500,600,700,1000

# Bank 2
1. Wholetone 0,2,4,6,8,10
2. Diminish 0,2,3,5,6,8,9,11
3. Combination Diminish ?
4. Ionian 0,2,4,5,7,9,11
5. Dorian 0,2,3,5,7,9,10

# Bank 3
1. Phrygian 0,1,3,5,7,8,10
2. Lydian 0,2,4,6,7,9,11
3. Mixolydian 0,2,4,5,7,9,10
4. Aeolian 0,2,3,5,7,8,10
5. Locrian 0,1,3,5,6,8,10

# Bank 4
1. Raga Bhairav ?
2. Raga Gamanasrama ?
3. Raga Todi ?
4. Spanish Scale 0,1,4,5,7,8,10
5. Gypsy Scale ?

# Bank 5
1. Arabian Scale ?
2. Egyptian Scale ?
3. Hawaiian Scale ?
4. Bali Island Pelog ?
5. Japanese Miyakobushi ?

[woelfl]

The calibration process is IMHO a bit

I just measured the output voltages with DMM. With main pot (B) fully CCW you obviously get 0V on all outputs (P, R, Q). If you're tuning C1 to 0V that means you'll get C5 with 4V (because "V/Oct", right?) So, with B fully CW, use G/H/I to get 4V on their respective outputs, P/R/Q. When done and double-checked, "A" to exit calibration and that's it. Simpler and faster than what's in the manual.

But then I wonder what's the point of those 3 trims in the back? If calibration is done with the tall trimpots on the front and those trims in the back are supposed to be left fully CW (as per build instructions), then why can't they just be replaced with fixed resistors, which would lower the BOM cost BTW...? While at it, what's the point of rectifying DC?

Otherwise, this caught my eye not long after it came out, I'm really glad I finally got one, I'd say this is one of the most creative module designs I've ever seen.

There's obviously some room for improvements, like e.g. extending the CV range to cover at least full 0-5V range, or even make it generate both positive and negative voltages... would require a few more bits in the analog domain, but the current BOM can be optimized anyway, and this would make it a lot better... If there's a new version with some improvements such as these, I'd get at least two more...

[BlinkyLights]

We have a full Robaux restock at Thonk this week too

Dope, this and the PO33 adapter kit have been on my Waiting List for a hot minute. You guys any closer to putting together the PO33 kits? I know you have all the stuff...

[pmboos]

After chatting to the module designer I realised that the instructions for calibration are actually slightly ambiguous - I was trying to calibrate using the trimpots on the back of the module and you're supposed to use the actual pots on the front

Even then... for me I can't calibrate it higher than 4.8v.
Pots on the back all the way max and tuning with the knobs at the front.

Did you work it out?

Yeah, I couldn't get it higher than 4.8v either, so I just programmed it with a 4 octave range instead of 5.

Wait you don't use the trim pots on the back? I was going to install and calibrate mine tomorrow...

So I am guessing you just tuned it to C4 since it couldn't reach C5? (Or did you just do yours via voltage?)

Thinking on that; I bought mine pre-built, maybe I don't need to bother with calibration.

I'm looking forward to playing with this... I love the interface on it.

[aragorn23]

So I am guessing you just tuned it to C4 since it couldn't reach C5? (Or did you just do yours via voltage?)

Thinking on that; I bought mine pre-built, maybe I don't need to bother with calibration.

Yeah, I just tuned to C4. If it's pre-built, you're probably fine.