OPx-4 Manual – Figuring it out, supplementing the Manual

Neodymium wrote:When you say 'Operator Modulation', do you mean Frequency Modulation?

Yes.

Neodymium wrote: And if so, do you mean a negative value in the Operator Matrix, or frequency modulation as a modulation destination from one of the 32 modulation slots?

The negative value in the matrix. I could find no references of FM synthesis with a negative "FM index".

If nobody knows I will have to reverse engineer it with another synth.

I couldn't answer my last question myself yet. But I have started to make some screenshots and collect notes to fill the gaps in the manual.

https://1drv.ms/w/c/6b243d16dcad2b94/EQ ... w?e=ZSJqUH

Well, not the best manual I have read so far.
The difficult but very useful part to understand is the modulation matrix, which is the core of this plugin.
Sending a source to a destination is where the magic weird begins.
But the GUI doesn't help, having to scroll here and there and so on.
I think the best way to use this OPx4 is to scroll through presets, find the one that is similar to what you look for and start by putting down all oscillators volumes and then raise each one alone to understand what is this oscillator sound exactly.
Then you can tweak each oscillator parameters, envelopes, pW, filters and so on.
After that you mix the 4 oscillators and start adventuring on the modulation matrix.
It's a complicated one but really really inspiring, especially for weird textures or tiny rythmic weirdos.

Straker wrote:Well, not the best manual I have read so far.
The difficult but very useful part to understand is the modulation matrix, which is the core of this plugin.
Sending a source to a destination is where the magic weird begins.
But the GUI doesn't help, having to scroll here and there and so on.
I think the best way to use this OPx4 is to scroll through presets, find the one that is similar to what you look for and start by putting down all oscillators volumes and then raise each one alone to understand what is this oscillator sound exactly.
Then you can tweak each oscillator parameters, envelopes, pW, filters and so on.
After that you mix the 4 oscillators and start adventuring on the modulation matrix.
It's a complicated one but really really inspiring, especially for weird textures or tiny rythmic weirdos.

Joe Filburn on YT has a really deep 7 part series on OPx-4 that you may be interested in if you haven't seen it already.

B-Wise wrote:

Straker wrote:Well, not the best manual I have read so far.
The difficult but very useful part to understand is the modulation matrix, which is the core of this plugin.
Sending a source to a destination is where the magic weird begins.
But the GUI doesn't help, having to scroll here and there and so on.
I think the best way to use this OPx4 is to scroll through presets, find the one that is similar to what you look for and start by putting down all oscillators volumes and then raise each one alone to understand what is this oscillator sound exactly.
Then you can tweak each oscillator parameters, envelopes, pW, filters and so on.
After that you mix the 4 oscillators and start adventuring on the modulation matrix.
It's a complicated one but really really inspiring, especially for weird textures or tiny rythmic weirdos.

Joe Filburn on YT has a really deep 7 part series on OPx-4 that you may be interested in if you haven't seen it already.

Yep, thanks a lot for the hint, I will watch it for sure.
I am really liking this Opx4, it's a real wonder, you can dig it for hours and discover sounds of any kind.
It can lead you to some rythmic and pulsing sounds that can actually be sampled and used as beats or tweaked to change all time with macros.
The modulation page and LFOs as sources to send in any destination you want are very important, if you sync them.
I will check YT Filburn tomorrow, thanks a lot.

Masi wrote:I couldn't answer my last question myself yet. But I have started to make some screenshots and collect notes to fill the gaps in the manual.

https://1drv.ms/w/c/6b243d16dcad2b94/EQ ... w?e=ZSJqUH

I've been re-assigning all my 96 midi assigns for my launch Control, as they didn't carry over from version 2.5 to 3.6. Had me studying this synth again. It's still not my go to but I come back to it again and again. Last night I discovered the self modulating (the operator not me) +4% produced a cleaner sin wave. Just saw your document and that you had found it before. I hope you come back to the project like I have.

When Novation bought out the new Launch control XL3, I was worried that stocks of the XL Mk2 would stop being available in Vietnam and picked up a second. This really opens up the feel of the synth, makes it much more of an analogue experience.

I reported the Midi learn switched labelling for FM Shape and FM Filtering that I reported in 2.2 and this time the technical guys agreed.

Also a new issue, is after assigning all the midi learns for the OPX4, when you reopen the order they are displayed in gets mixed up. They're still correctly assigned, just listed in a nonsensical way. They are looking into that.

Back in March 2024 I had said I could click on the VST version to enter ratio, offset and matrix value manually. Others said they couldn't and I retested in December 2024 saying it was working. I'm guessing I was on an earlier version, and have since updated to the same one as them, as I can't do this anymore, and reported today.

Seems like they've messed up the VST version along time ago. Probably not done them many favours with those outside the MPC community. If you want to be able to be to manually enter the Ratio, Offset, FM Matrix amount, FM Filtering and FM Shaping, you'll need to roll all the way back to 1.1.0 release.

I've also asked them to make right click plus CMD key make Ratio go to 1.000, Offset go to 0.00 and FM Matric amount go to 0. (they go to 0.000, -9.999.00 and -100 at the moment)
And I asked for shift fine tune for dragging levels


Today I learnt something cool about the effects. I normally turn off the effects in the plug ins and use the track effects, but because there are 3 parallel effects (one for each submix) the OPX-4 FX offer something extra. I had noticed that one control in each effects has a purple ring highlighting it. this means it can be modulated. So an envelope can be assigned to modulate the depth of Chorus/Flanger/Ensemble or Phaser, With delay if can be assigned to Mix. so you can fad in a delay effect, then cut it off with a short release. Or assign an LFO to drive amount of the tube drive.

I still feel like I'm at the beginning of a learning curve with this synth, and that less is more, but lots of less is is even more. I'll be investigating a bass sound, and then play it as a chord and be struck by how cool it sounds, then play it single notes higher and be surprised again.

Sources and Targets from the Modulation matrix. Target list is also used in Midi Learn. Stupidly big list to scroll through. Hopefully this list will make it easier to find.

Lampdog wrote:OPx4 feels endless to me. It just never stops being good.

Seems very easy to get into unstable nasty territory. I've not used other dedicated FM synths (beyond things like my 2 operator LXR-02 and other simple engines), so I don't know how typical that is. I do really enjoy the formant and PW option for making it go beyond sine waves, and the matrix instead of having to choose a algorithm. I have the Hydrasynth and on seeing ASMs new FM synth released this year, even though it's out of my price range I a firm 'no thanks', that's just way to deep, where do you stop? I would be tempted by the OPSix, if it wasn't for having the OPX4. And with 2 Launch Controls attached, it's really hands of, kind of analogue feeling (not sounding). I have it on 3 banks, so one of the Launch Control jumps between banks. But if I saw another Launch control at a discounted price I wouldn't hesitate.