With 741s are you using a dual or single power to the chips?
Thanks

My original mistake (which paused me for a few months), was using a single power supply. I finally read "...most op amps like a (dual?) power supply...".
So I am using a +/- 9V power supply, even though all the CVs I'm using are (theoretically) positive. I guess, even if I use a 'Non-Inverting Amplifier' circuit, internally the signal must need negative voltages.

Does that make sense?

Aside from a back-to-back pair of 9V batteries, my power supply is a pair of back-to-back DC wall warts (not too close to 9V). I use 3 conductor PWM cables (black/red/white(yellow)) for convenient power cables.

I think I have used a single PS with a 741, but probably had a voltage divider for the 'ground'. (Not sure if that's legal.)

Just a question: Does anyone know, what exactly does the firmware update to version 0108 change (so far the latest one)?
Thank you for answering.
Enjoy your day!
rolf

quoting you here for continuity - don't quite feel up to reading entire thread, or scouring YT right now. as you read, i'm not impressed with it at this point. even wondering if it is working properly > n00b - i got it 2nd hand (vgc, looks great, in box 'as new', even has orig. batteries)

i should be scouring the manual and example patches. (print too small.. have to download pdfs)

It does look nice and have left on shelf next to Waldorf 2 Pole and Vermona Retroverb. But unlike the latter items, the Volca Modular sits unplugged.

So as an art installation, the Korg Volca Modular is nice to have "hanging around"!

(whinge suppressed :P)

yeah so, i'm getting what you mean, about putting it away and hanging onto it. sort of wondering what it would be like plugged into something else, because it's quite limited really. lack of midi is a killer, don't know why they didn't include the optocoupler on those inputs. so far i've run off audio while tinkering with it. don't even know if this one fully works - what does LPG2 do? can you plug outputs into outputs? it sometimes does something like this. it IS very pretty, and cables do fall out. puzzling when you pull some out and the sound doesn't change... ?:-/ do i have time for this? it's triggering a latent fury/aversion about modular

I think I found a use for it after all.
My Retroverb has a VCA on it so when I make sine wave sounds I can attenuate
the sounds through it AR envelope.

My 2 Pole does not have VCA but I might ignore the oscillator signal components of the Korg Modular and feed the signal from the 2 Pole direct to the Low Pass Gate and use my midi clock to trigger to gate the envelope of LPG.

Round about way, but now I have to make due with what I have.
Gear-sluttery funds have been cut to the bone!

(I hung up my Gearsluttery way in late 2018, my last new synth purchase)

Here is the Waldorf 2 Pole routed through the Volca Modular as a VCA.

nice. so the vMod is 'letting through' the signal from the other stuff ... ?

um.. aaah.. of course you know that as soon as (i) sell it, korg will bring out the other half as a different volca modular pt2, or something. i just find it too grating as it is. probably don't understand it, and should 'work' harder at it.

i'm not really of a mindset to try to make it work better, with other stuff (maybe). did think about pulling out signals from the pcb connections on other volcas eg: bass/keys - already have a piece of ribbon picking up all the wave outputs inside a Bass, thinking about attaching those to a piece of ribbon header, instead of having minijack outputs. the ribbon header presumably would take dupont cables? (2: do i *need* to sell it, other than for headspace? rid myself of underwhelm?) (name for a band/track?) (movie?)

Yep and all I use is one Dupont connector.
The CV In on the VM can also be used as external input from other synths.

So the 2 Pole 1/4" signal OUT connector gets converted to 1/8" and goes into the
CV Input jack on the Modular.

The Top position on the CV area goes to the signal IN on
the first LPG via the one Dupont cable.

So now all the internal signals from the Modular are bypassed
and the LPG/VCA can control external inputs.

In order to synch the Modular's first EG, I take a trigger pulse from CV OCD,
which ensure the attenuation is done to the beat.

I've been loosely following this thread, thinking I should contribute some ways that I find the VModular interesting.... (but I'm lazy). So interesting, I bought a 2nd one, which is tough for a tight budget...
One of the things I love is the sequencer: the unusual scales, especially the stochastic mode, and the usual (for Korg) Active Steps (LOVE those!, a swipe of the finger, and a new sequence, and back again!).
Too bad it didn't have MIDI out, but I breadboarded a Pitch CV scale and offset circuit, so I can use the sequencer to drive my other synths (Neutron, Crave, etc.)
The sound is unusual, and I like it, but I know what you mean about it being hard to get anything aside from a standard. Takes some getting used to....

well i was thinking that could be a way to get more out of it.
notably i could try to prototype the optocoupler like that and put a provisional TRS minijack on the case, wired to the pads, with the optocoupler circuit on a breadboard outside while i get it to work - having scavenged the parts off a home keyboard found in the bin; the circuit looks pretty simple, and we have the info/schematic.

beyond that, try some other stuff, and it becomes a kind of project lab. but i don't really see it as part of any midi rig at this point.

i still don't really grasp the different input types, and i've got results plugging an output into an output ?:-/ - LPG2 doesn't seem to do much (although i occasionally get it to do something. am i supposed to chain it with LPG1?) and i'm not clear on what to do with the cutoff maths bit - mostly, having to look up patch sheets and copy feels like cheating.

what's it like with 2 of them? i half expect korg to bring out something that will interface with it. and as mine is 2nd hand, does it even work properly?

edit: aaaargggh !!!

Well, if you DO throw it out, which garbage bin? Or maybe I'll trade you my 'just arrived' Moog Werkstatt, for which I have low expectations.

If you want, I can look up my "Pitch CV/Gate Out" circuit for you. A couple of op amps, 2 pots and some kind of connector. (And a lot of patience tuning it.)

I guess that I came into the Volca Mod after having a couple of Microbrutes, an MS-20 Mini, and some background in electronics, which may explain why I like it: I think voltages. I've since added a Crave and a Neutron. So I guess I really LIKE (semi) modular, although I can't afford to fall down the full modular rabbit hole.

Another thing: I guess I don't think of the Volca Mod as a particularly good sound module: I think of it as more of an additional set of modules, which happen to have all the stuff to make a sound.

The Low Pass Gate: Cutoff does filter out sound, but it decreases the volume simultaneously, so a lot of times it just seems like a gate. Changing it a little bit will change the sound timbre, but changing it a lot just turns the sound on/off.

One thing I'm always looking for: a CV controlled envelope, or at least Release. I worked out one with the Volca Mod:

Clock / 4 --> Woggle Trigger
Woggle Step --> Function Generator 1 Decay
FG1 (+) --> Gate Out (gives a variable length gate on the next synth)

the one labelled 'Modular', next to 'Moog' :P

my post was meant to be humorous of course.
i did get a new decent triangle wave bass thing out of it today. if only it had midi.

so are you saying it interfaces ok with other gear? i thought volcas had their own internal voltage standard.

right, i *think* LPG2 is working as it should (? .. occasionally does what i want it to?), and the... 'utility' section did something earlier. (so hopefully it is fully functional)

turns out that the 'woggle' sends Noise *out* of the Sample input.
what other inputs can be use as outputs? and i know understand how the Functions differ. but what is End Trigger for?

i don't know what Clock Offset does.
and i was thinking that blue is always and ouput. not on Source, it seems.

it's doing something weird atm, slow random intermittent beaky/honky noises. not immediately useful...

It seems you can never get rid of the the internal oscillator.
Just like a Monotribe the VCA will only open with the sequencer on OR the Vmod can bypass the sequencer with the LPG gated on.
Even so, if you feed an external signal to the LPG input with Gated On VCA you still get triangle wave bleed.
Is it possible to short out the VCO so it won't bleed through on external signal processing?

still at the stage of enjoying that triangle atm
pulling Modulator and Carrier out to other things.
got some good sounds out of it the other night.

it is perhaps a 'Dual LPG', rather than 2x LPG. i need to study that a bit.
https://electronicmusic.fandom.com/wiki/Lowpass_gate

i did get to wondering what hardware mods could be done to it, or simple circuits on breadboard. can anything act as an AND gate?
what are you doing to interface pedals with it?

i don't actually have anything as an easy external cv&gate source at the moment. arturia keystep maybe? has patterns, unlike the SQ1 - although that could do authentic 'row' sequencing.

Q: does the sequencer record cv&gate input to onboard patterns?

To test LPG2, set up a basic sound and use the LPG2 instead of LPG1...Run a patchcord from Function1 (+ Out) to LPG2 (Control In), then a cord from Source (Out) to LPG2 (Audio In). Slowly turn the cutoff down and see if you lose harmonics as well as volume. Maybe use some Fold and Mod on the Source, to have some higher harmonics for the LPG2 to affect.




END TRIGGER:
Connect the Pulse Out (end trigger) back to the Pulse In (for either Function 1 or 2) and the envelope will re-trigger itself. Function2 then makes a nice LFO.

CLOCK OFFSET:
Patch the Woggle Out into the Clock In, and play a sequence. It should speed up and slow down.

BLUE OUTPUTS (on Source): the last two holes here ARE outputs, the 1st one (5th in the whole set) is the audio out for the MOD oscillator, pitch set by the keyboard as well as the Ratio knob. The last output is the main oscillator. You may have seen a patch where the MOD output goes to LPG2 (triggered by Clock Pulse out), to have a dual oscillator.

Interesting note you made about the Woggle (Audio IN), that it outputs noise! That must be picking up the internal (normalized) connection. So the noise source is available, not just through the Woggle out. I'll have to look at it on the scope.

Yes, I've been able to get signals in/out. It does have it's own standard: I measured the pitch out as ~ 0.6 V/octave. Don't quote me on that: I have to look it up. Anyways, I made a circuit that amplifies that to 1.0 V/octave, then shifts it down to a usable range.

I don't doubt you, but I can't hear any of the onboard VCO bleeding through. (Course, I taught high school for 30 years; what CAN I hear anymore!)

I piped an external source into the LPG1, fully open, gated with the sequencer or keyboard. I hear the external source, and when I turn that off, I hear nothing. (The external source does sound a little different; low fi somehow?).

The Behringer Neutron (or Crave?) does have that property: the VCO hardwired to the filter/amp. So I ended up taking the VCO output, inverting it, adding it to the source I wanted, then feeding that in. It canceled out the original VCO signal and voila!

https://www.ebay.co.uk/itm/10-x-40-w...4AAOSwmtJXWcLU

https://www.ebay.co.uk/itm/10x-20-wa...75.c100623.m-1

anyone thought of adding extra dupont ins/outs? eg: to Bass and Keys labelled pcb points.

I haven't opened it up yet; are there points on the PCB labelled Bass and Keys, or do you mean points on the Volca Bass and Volca Keys?

I keep a proto board next to my VMod, for I/O purposes. The Dupont cables go nicely into that, straight from any (existing) socket on the VMod.

I use these "Screw terminal TS sockets" to interface with patchcords....


https://www.amazon.com/gp/product/B0...?ie=UTF8&psc=1

wow those look brilliant, didn't know they existed.

'Bass/Keys' was a reference to the other volcas - those ones have outputs for oscillators on the PCB, saw and square for each, too many to want minijack sockets, so a row of dupont holes would be fairly easy to do, and would fit under the volca pcb. and go for contrasting colour, in order to see the holes better - than black. they should have gone for a cream, or blue (nice 'functional' colour).

needs a 2x TS/mono 1/8" to mini TRS/stereo for the cv&gate. have to try driving this thing with TD-3 managed to get some creaky sounds out of it, would be quite nasty with slides etc. ( - can an LPG be set up to detect amplitude? .. )

am into trying some external circuits on breadboard. something like a sync distributor using logic gates would be interesting with multiple volcas. so that could be a set of cmos ICs with a patching section, on a breadboard? ..


Q: why is the Sample&Hold section called 'Woggle' ?

To stick them on a breadboard, I put a (standard) paper clip into the screw terminal, then cut it off to the right length. Then just insert it into the breadboard where needed. If I hot glue 2-3 together side-by-side, they're pretty stable, but I still have to hold the socket when pulling out a patch cord. All kinds of uses for them; I keep buying more and more. (One of my 'brilliant/useless moments: Inserted a bipolar LED with R in series (in a male plug). Now I plug the plug into a modulation source (LFO) and watch the LED go red...green...red... As if there aren't enough lights flashing in my face.)



Couldn't a sync distributor (?) be made with just an op amp voltage follower? That should have enough current to drive several Sync In ports (even if not buffered very well).



I don't know. I suspect it's a takeoff on 'wiggle', California-style?

more something to mess around with clock pulses, letting them through or not. clocks and gate signals.

was looking at this. sp3t switches 2 capacitances. what's that?

Not sure I understand that, but I would like to try the LED/LDR (vactrol?) sometime. Is this supposed to pass/not pass GATE and CLOCK signals? Or act as an envelope? The capacitors would introduce a delay? And depending on the CV, the gate/clock would pass or not? (Sorry, I'm not real good at analyzing circuit functions.)

IF you just want controlled passing of gate signals, you might consider a "CD4066: Quad Bilateral Analog Switch". I have some sitting here, but haven't used them yet. Just a voltage controlled switch, from what I can tell.

I just got a Volca Modular and I'm starting to get around it. I have a couple of questions:

1- I updated to firmware 1.08 (which in itself was a pretty big headache, I couldn't get the .wav file to work from any sound source) and tried to calibrate the CV input, but i'm not sure it worked.
When I try to control it from another CV synth, oscillator tracking is bad but most of all, the timbre is totally different from the normal sound played from the touch keyboard: instead of clean triangle waves, I get a sort of dirty, wobbly, distorted sound. Maybe I did something wrong during calibration?

2- I read various posts about interfacing the Volca's modules with other CV synths like Microbrutes, MS-20 etc: how do you do that, given the breadboard connectors? Right now I can only interface the Modular with my Werkstatt which also has dupont connectors...

Apart from that, I'm still exploring and I'm amazed by the amount of online resources there are...so much to learn!
Thanks for any hint!