MPC X, MPC Live, MPC One & MPC Key 61 Forum: Support and discussion for the MPC X, MPC Live, MPC Live II, MPC One & MPC Key 61; Akai's current generation of standalone MPCs.
By Big Tick Wed Nov 23, 2022 7:27 pm
Neodymium wrote:FM Shaping
This has me a bit puzzle to what it’s doing exactly. It seems to be shaping the wave resulting is removal of high frequency noise, but having less impact on the harmonics than the FM Filter has. When the source is quite stable it doesn’t seem to have much impact, whereas filtering always does.


The effect is more obvious if you set up a simple patch with one single oscillator self-modulating at 100%, with FM filtering at 100% to reduce the harsh noise.

With FM Shaping at 0 you get a saw-wave type of sound.
With FM Shaping at 100 you get a square wave.
By chrisroland Sun Feb 26, 2023 6:15 am
not just specific to the OPx-4 (although it seems the most complex of the plugins) but one downside to dropping a new one or five every few months is the friction of now having to learn another workflow to take full advantage of the plugin and not just preset dive every time you want to use one in a track. i'll certainly get to this eventually (still have to master Digitone's FM synthesis at the same time) but i do find myself putting that off in favor of just writing stuff with what's in the box
By Big Tick Mon Feb 27, 2023 8:10 pm
JRock wrote:What are the 5th and 6th envelope normalled to?
I believe the 5th is a "VCA" after the matrix...
But not positive. Just started poking around with this.
That operators chart is SUPER Helpful.


env5 and 6 aren't wired to anything, but are available as modulation sources.
By JRock Mon Mar 27, 2023 2:24 am
I've been making a few more patches, one thing that was a little confusing to me was the Modulation Section Abbreviations (which the manual doesn't even make mention of). There are choices to target the FMxx. I believe the first number is the Carrier, and the second is the Modulator.
FM21 = Operator 2 being modulated by Operator 1.
Just felt like I should mark this down while it's fresh in my mind (that way I can look it up when I forget XD ).
It may be self evident (and I may have it backwards, in which case please correct me), but I had to experiment a little to figure it out.
By Straker Mon Mar 27, 2023 4:14 pm
Yeah man, very very good post.
A lot of very useful informations.
I just purchased opx4 and I am starting to get it, it's a supercool work from Air.
Having used a dx7 eons ago and a microfreak recently, I can clearly get where the inspiration comes from.
Opx4 is perfect to reach weird and interesting experimental sounds, something you cannot achieve with the others mpc plugins.
So it's a great idea to put this opx4 and at 29$ is really worth.
Just one thing: presets are from bad to awful, this FM synth works much better if you start from init and go to unknown territories, that's the very cool thing about it.
Is it real that the INIT preset is wrong?
It sounds right to me.
By JRock Wed Mar 29, 2023 1:36 am
Awesome right?
A fully fledged FM synth (with an accessible GUI, and transparent parameters) right in my MPC (portable even, with the Live II).
It's not necessarily "wrong", but it's not Empty / Clear.
Poke through the Modulations and you'll see a BUNCH that are still active, and not needed.
Mod 17 is LFO1 tied to Transpose.
Mod 18 has the KeyBoard Note controlling the FM Scaling (makes it so Higher notes will increase the FM %).
etc.
It's as Simple as going through and making sure they're toggled off, but if you haven't, you might be trying to track down why your settings are not doing exactly what you programmed them to do.
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By hyena Wed Mar 29, 2023 4:20 pm
also, the init sound is not a pure sine wave, you have to make adjustments to get that, and the wave shape is almost always sensitive to velocity unless you kill all your velocity settings. not a big deal, but if you need to have a sound that starts as a pure sine wave the default is not it, it already has some harmonics.
anyway, after some months with it i confirm my first impressions, very cool synth, like the hidden son of Fm8 and Operator :)
the coolest thing is the easy fm matrix, not having to stick to algorithms is a gift, but at the same time is more streamlined than Fm8, in this it has some resemblance to Operator. the modulation matrix still puzzles me from time to time, i still have to explore and understand what the various modulation shapers do and how they practically work.
By kvantoompc Tue Aug 29, 2023 5:42 pm
Just putting down some notes as they're fresh...
::No dedicated pitch envelope but can use Envelope 5/6 for this: assign a Modulation targeting the Carrier's Offset
:: Can't label the macros come on?! Akai gives us quite long filenames though, save it with maybe
:: Envelopes should be shown a bit more stretched horizontally, boxes and interconnecting lines are overlapping for short envelopes
:: List of target/source is a mess, thanks Akai the feel of the cheese grinder knob always a pleasure

Great synth, just did an Operator preset reprogram and it knows everything....MPC UI is well done too!
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By Neodymium Sat Feb 10, 2024 3:31 pm
Some late replies as I preoccupied with some other things when these responses were posted. Trying to get my head backing to this synth again, and and working on something to help opening it up.

Big Tick wrote:
Neodymium wrote:Does anyone know the difference between Velocity 1 and 2 in the Modulation sources?


Yes. You have 2 velocity curves controlled by the VEL CURVE 1 and 2 on the "utilities" tab.



I was more confused by a track only having one velocity, so how can their be two curves. But I think I get it now. You can make two different responses to the velocity. You can make one more logarithmic and one more exponential, and the choose between them to assign to different modulation sources. So filter could be Dynamic and logarithmic and an amp less dynamic and also exponential. I guess this is particularly useful when you have 4 amps going on with 4 different operators and 2 filters all at once.