John Bowen Synth Design

[quote=poly bonk post_id=23702 time=1590667102 user_id=84]
Its [url=https://www.outlookindia.com/outlook-spotlight/phenq-review-thinking-of-ordering-phenq-read-this-first-news-221656]interesting review of phenq[/url]. I have always wondered why I can get all this insane sonic evolving territory on the JP6 that I cannot get on any other FM implementation. Maybe its the multiple waveforms combined within the VCO's that give it the unique effect.

Do you think that routing several oscillators into a mixer and then using them to do FM on one of the oscillators would do something similar?

On this site someone was asking the same thing and says:
"A few (vague) sources on internet forums suggest that the cross-modulation is exponential frequency modulation of oscillator-1 by oscillator-2."

https://music.stackexchange.com/questions/57210/what-exactly-is-the-cross-modulation-on-roland-jupiter-and-jx-analog-synthesiz
[/quote]



Nice track shared by @polybonk

I got X-MOD on my JP-8000, sounds extremely digitally agressive when I play it. But might investigate again to see if I can get JP-6 results but I doubt it :p

Its interesting that. I have always wondered why I can get all this insane sonic evolving territory on the JP6 that I cannot get on any other FM implementation. Maybe its the multiple waveforms combined within the VCO's that give it the unique effect.

Do you think that routing several oscillators into a mixer and then using them to do FM on one of the oscillators would do something similar?

On this site someone was asking the same thing and says:
"A few (vague) sources on internet forums suggest that the cross-modulation is exponential frequency modulation of oscillator-1 by oscillator-2."

https://music.stackexchange.com/questions/57210/what-exactly-is-the-cross-modulation-on-roland-jupiter-and-jx-analog-synthesiz

Well, I’m not sure if this is really correct, as I see at https://electricdruid.net/roland-cross-mod-metal-sync/ the author states,
>
> Jupiter 8 “Cross Mod” is FM from VCO2 modulating VCO-1. This is described in the manual as “ring modulation style effects” which is true in as far as they can both produce non-harmonically related pitches. Technically, they’re not similar at all.
>
> Note that this FM is fed to the 1V/Oct CV input of the oscillator, so it is exponential FM, not linear FM.
>
> The Jupiter 8 also offers classic hard sync from VCO-1 (master) to VCO-2 (slave) with its “sync” switch.
> Jupiter 6 Cross Mod and Sync
>
> Jupiter 6 “Cross Mod” is FM from VCO-2 to VCO-1, just like the Jupiter 8. There is a CEM3360 VCA which controls the amount of FM, and this can >be set manually (the “Manual” slider in the Cross Mod section) or via Env-1 (the “Env-1” slider in the Cross Mod section). The Jupiter 6 is more >sophisticated than the Jupiter 8 in this respect – it allows envelope-controlled FM depth, whereas FM depth is a fixed setting on the Jupiter-8.


So, is it exponential or logarithmic FM?

Thanks for the info T_tangent


Hey John.
No problems. Here you go.
This Jupiter 6 is in need of a service so some of the voices are out from one another unfortunately. But its close enough.

https://soundcloud.com/polybonk/full-crossmod-multiple-keys-2

So Logarithmic FM hey. Is that something we could do with the AM modulators? I don't have Solaris hooked up at the moment so I cant remember.

Well, it’s interesting that he states it is logarithmic FM instead of Exponential FM. That is a key to the results you are hearing.

Could you make an example of the 2 saw waves that you did, with the Cross Mod at full amount, then play across the keyboard, say, C2 E2 G2 C3 E3 G3, etc.?

Not sure if the following links are of any use but they have some related info on the JP6 Cross Mod so I figured I would post them just in case. :)

http://www.florian-anwander.de/roland_jp6/
Modification No.2: Change logarithmic VCO2-to-VC01-modulation to linear FM

and

https://www.gearslutz.com/board/showpost.php?p=14008408&postcount=73

I tried this mod out a while ago but in the end I seem to recall reverting back to the original Cross Mod as I preferred the whackier timbres it produced.

Another example of how wild it can get with the Cross mod on the JP6
https://soundcloud.com/polybonk/jp6-crossmod-swamp

2 layers this time. One of them into a delay. More sound design territory than musical.
I really appreciate you taking the time with this. I have always wondered what Solaris would be like if I could recreate this kind of structure.

On a side note I have almost completed a full sound bank of patches to share with everyone.

Thanks so much for your help.

Thanks for looking into that.
This recording is from 2002 and just meant to convey how much evolution/harmonic tonal content that continues to come in and out.

Would have been 2 notes on upper and 4 on lower.

This might help
https://soundcloud.com/polybonk/jp6-xmod-middle-c-2-saws-then-osc-1-square-several-octaves-down-osc-2-sine

Here is middle c 2 saw waves and I turn up the crossmod. Then a second go Then Osc 1 Square Several Octaves Down Osc 2 Sine.
This really doesn't convey just how deep it gets when you use multiple notes and multiple waveforms all at the same time.
Then you can get worlds of shifting harmonic content.

A quick lookup of the Jupiter 6 states that the splits limit one side to 4 voices and the other side to 2 voices. That means one of the sides isn’t playing a ‘chord’, but in any case, it would be good to get a single dry sound example to analyze. Perhaps you can record without a split a single sound using cross mod, and to play it up and down the keyboard. List the waveshapes involved, tuning ranges, etc., so we can better try to figure out things.

Another reference states: "Note that this FM is fed to the 1V/Oct CV input of the oscillator, so it is exponential FM, not linear FM.”

So, what we need to know:

1) what are the 2 waveshapes involved?
2) what is the tuning of both oscillators?
3) what is the depth of Exponential FM (what is the mod amount)?
4) what notes are you playing?

And I would like to know these points for both of the patches used in the split configuration.

Well, I’d need more information. What are the Splits made of? What waveshapes? To start it, you play 2 chords...are they one chord for each side of the split? Are they the same chords for each? Can you just isolate one note without any effects so I can hear what it sounds like?
I am completely unfamiliar with the Roland gear.

Actually I will use soundcloud to keep the question relevant to anyone reading.

Cross Modulation on a single Jupiter 6. Split upper and lower with keys in hold mode. Some delay used that creates the panning. Ping pong on the VS 880 HD recorder.

https://soundcloud.com/polybonk/in-the-forest-the-sleep-edit

Everything that you can hear happening is all 2 JP6 parts deep in Crossmod with the keys set to hold a dual layer drone of 2 chords.

Nothing is being touched on the synth. Its playing itself.

Hmm thanks for the info.
Jupiter 8 is definitely ordinary sounding FM. JP6 is utterly unique tho.
I did find online once someone said that JP6 cross mod was actually some kind of AM mod when I went asking in a forum years ago.

Its absolutely crazy what it can do. Like a wall of constantly evolving modular. I was hoping it was possible with the AM modulators in the Solaris.
I will email you an example of what I am talking about so you can hear how unusual it is. If anything could do that stuff it would be Solaris.

On most of my patches I mod the pitch and FM of osc 1 to 2 and 2 to 1 at the same time to create rich string like overtones.
Im often finding that the resolution of Solaris pitch destination is way too crude tho. Its like I need a lot more steps of resolution between 0 and 0.10

Is there a control solution that could use as an offset to get better resolution? Damp down the % somewhat?

I also found this online:

"In the early VCO-based instruments, Roland used “Cross Mod” to mean frequency modulation (FM) of one oscillator by the other. The term is used this way in the Jupiter 8, Jupiter 6, and the MKS-80 module. These are the only synths that have this option."

It depends on what and how the Jupiter 6 is processing what they call Cross Mod. I know in a number of earlier synths, this was just audio rate modulation of the frequency, but it could also be modulating the VCA, or even the Pulse Width.
Since the Solaris has several ways to modulate the amplitude (in addition to Ring, there’s several others), you should try using the mod Source of 1 osc to Linear FM destination of the 2nd osc, or try Exponential FM (Pitch in the Solaris mod paths) to see if either of those come close to what you want.