Analog random control signal emulation

User Feature Request List

Moderator: Solaris Moderators

alexg
Posts: 30
Joined: Sun Jul 24, 2011 1:33 pm
Location: France

Analog random control signal emulation

Post by alexg » Fri Sep 30, 2011 8:15 am

As discussed in another part of the forum, it would be fantastic to have an ‘analog random’ control signal, to give some adjustable drift to the pitch or phase of the oscillators and to the filters and eg's.

John Bowen
Site Admin
Posts: 1729
Joined: Sat Apr 07, 2007 3:00 am

Re: Analog random control signal emulation

Post by John Bowen » Fri Sep 30, 2011 9:57 am

Yes, this was in the original specification, and never got included for some reason (unknown to me).

serena-5
Posts: 46
Joined: Fri Mar 28, 2008 8:22 pm

Re: Analog random control signal emulation

Post by serena-5 » Fri Dec 30, 2011 11:23 am

Even though this synth sounds amazingly analog, this feature might be very useful. Is there any chance of this feature being added in a OS update, John ??

John Bowen
Site Admin
Posts: 1729
Joined: Sat Apr 07, 2007 3:00 am

Re: Analog random control signal emulation

Post by John Bowen » Fri Dec 30, 2011 12:49 pm

Yup, it’s on the list.

Actually, I’d appreciate everyone’s input as to how you’d expect to see this implemented. There’s simple, and then more complex....

1) Simple - use an LFO. Select S&H wave shape, Retrigger ON, Rate = 0. Now, with every key press, the LFO will put out a random value
2) More work - add a new Mod Source List item, called Note2 or Random Note. etc... All mod lists have to be updated. What kind of control would you have over the random output?
3) Complex - the randomness has a number of parameters, allows you to define the range of randomness, which functional blocks will be randomized, etc.

4) Maybe simple also - a single parameter in the System page that controls random or ‘analog slop’ for the synth in general.

Please let me know your opinions.

john b.

serena-5
Posts: 46
Joined: Fri Mar 28, 2008 8:22 pm

Re: Analog random control signal emulation

Post by serena-5 » Fri Dec 30, 2011 1:08 pm

It seems to me that the most accurate and "analog" proposal to this would be the third. If I understand you on this, the drift would be completely random, and would vary, in real time, just like a oscillator randomly drifting without retriggering. You could really hear it change in real time as you held a note by the second if the oscillators were tuned in "unison", but that was the charm of it.

alexg
Posts: 30
Joined: Sun Jul 24, 2011 1:33 pm
Location: France

Re: Analog random control signal emulation

Post by alexg » Wed Jan 04, 2012 9:42 am

For me, the second one would be enough.
Output would be :
- Oscillators tune
- Filters freq / res
- Envelopes attack decay release times

CA3080
Posts: 35
Joined: Sun Nov 25, 2007 11:06 am

Re: Analog random control signal emulation

Post by CA3080 » Wed Jan 04, 2012 1:31 pm

Randomness to simulate analogue synth circuits needs to be of (at least) two sorts.

First a couple of 'per voice' random values can be used to introduce variation between voices in, for example, oscillator frequency, shape, filter frequency, resonance, envelope times and voice pan. Since so many potential targets exist for this random variation, several (3? 4?) "VoiceRnd" values are needed. (John's method #2)

For variation over time within a voice, a slow random mod source is needed. I think this is mainly useful for control of oscillator frequency, so the modulation could be packaged as a single "Oscillator drift" control at the patch level. For optimal results each oscillator should probably have a unique random mod signal that is not the same for all voices. (John's method #4)

Since the human ear is very sensitive to pitch, successful introduction of random frequency control depends on high resolution control of the oscillator frequency. John, what is the osc freq resolution of Solaris, i.e. what is the smallest possible frequency change?

John Bowen
Site Admin
Posts: 1729
Joined: Sat Apr 07, 2007 3:00 am

Re: Analog random control signal emulation

Post by John Bowen » Wed Jan 04, 2012 2:00 pm

CA3080 has it correct, actually, as all of those things need randomization for better results.

To alexg - the output/destination does not need to be defined if VoiceRnd values are added to the Mod Source list - you just use them wherever you want in the system. Now, if you are talking about an overall setting, with the output predetermined/fixed, then yes, OK.

As for the minimum frequency resolution - good question....from the front panel we have adjustment by cents, and via the Modulation Path you have 1/10 of a semitone (10 cents) minimum stepping, however this can be less if you adjust the output at the source (for example, using an LFO as Mod Source, but setting the output Level to 1% gives you a VERY small, almost imperceptible amount of modulation.) Given that, I would say the resolution is high enough to do what you’re thinking.

Maybe we need to change the Mod Path resolution to 1 cent resolution...only when holding down the Shift key, though :-)

john b.

serena-5
Posts: 46
Joined: Fri Mar 28, 2008 8:22 pm

Re: Analog random control signal emulation

Post by serena-5 » Wed Jan 04, 2012 3:56 pm

Wow…this subject has gotten over my head. I guess for me, "random" is the key. I remember playing a on a Oberheim 8 voice, which would rotate voices (oscillators) with every key depression. One key depression yielded a perfect unison…the next would give a very slight (.6HZ) variation…maybe the next was off slightly as well, albeit different from the second…different, but all very random….and just enough to sound FAT, not out of tune. And unisons on my first MInimoog would drift slightly as you held a note (between all three oscillators), even after it had a warming period. The resulting sound was very fat and "animated", for lack of a better term. This is how I understood analog "syntheness".
Another very cool thing about the Oberheims was how the voices could be panned as well…when voices were rotated, they would pan differently in a stereo field with every key depression…extremely animated. I believe that this was addressed elsewhere in this blog, but I believe not possible with the Solaris…bummer.

John Bowen
Site Admin
Posts: 1729
Joined: Sat Apr 07, 2007 3:00 am

Re: Analog random control signal emulation

Post by John Bowen » Wed Jan 04, 2012 4:04 pm

Yeah, the panning thing is a bit different for digital versus the analog world, where you have discreet components producing each voice, and can therefore exactly route their outputs. I love that effect, though.

Also, the thing you are talking about with the Oberheim is what I call rotary assignment, and it’s also a favorite thing of mine from the old days. I even had Dave put that kind of thing in the Prophet 10 - it was so fun to play! You could get some great subtle variations from voice to voice (or not so subtle, if desired) if you used this setting between 2 different presets with the P-10.

So, this idea of the VoiceRandom value, or Random Note, or whatever - this would give you a different value for every key pressed, so you’d have the similar effect. This is something I definitely have in my spec from the beginning - it was just one of those things that didn’t get finished yet.

JB

serena-5
Posts: 46
Joined: Fri Mar 28, 2008 8:22 pm

Re: Analog random control signal emulation

Post by serena-5 » Wed Jan 04, 2012 4:53 pm

So…random note is possible with future OS updates I take it…but not rotary assignment ? As an interesting aside, I do remember on one of my all too frequent visits to Sequential Circuits up on First St., Riley in service demonstrated that feature to me on a P-10…but I assumed that it was one of his custom mods. That was, I believe, among the first "stereo" effects that I remember hearing. And hard panning really did enhance the effect. The Solaris with this feature would be unbelievable KILLER (or more so) !!

John Bowen
Site Admin
Posts: 1729
Joined: Sat Apr 07, 2007 3:00 am

Re: Analog random control signal emulation

Post by John Bowen » Wed Jan 04, 2012 6:17 pm

Yeah, that was a standard function on the P-10, not a ‘Riley Special’.

For the panning thing - while we can’t specify individually where each voice appears in the stereo field, a Random Note applied to modulate the Pan position should give a similar effect, just less control. It’s definitely something I want to have in the next OS.

JB

serena-5
Posts: 46
Joined: Fri Mar 28, 2008 8:22 pm

Re: Analog random control signal emulation

Post by serena-5 » Wed Jan 04, 2012 7:23 pm

Thanks, John. It's greatly appreciated that we can actually contact the designer of a synth, and have our voices heard/acknowledged. Try that with other other synth company !!

scope4live
Posts: 548
Joined: Tue Mar 04, 2008 4:19 pm
Location: Somewhere between 120 and 150bpm

Re: Analog random control signal emulation

Post by scope4live » Mon Jan 23, 2012 3:00 am

I just want Karnevil 9 style S & H.
That seems to be capable of adding to a song where the pitch stay soimewhat near the irginal pitch og the tune....
Magnus C350 on a TV Dinner Tray Stand with 2 x PigNose Amps for stereo


https://soundcloud.com/jimmyvee/wormhole

John Bowen
Site Admin
Posts: 1729
Joined: Sat Apr 07, 2007 3:00 am

Re: Analog random control signal emulation

Post by John Bowen » Mon Jan 23, 2012 7:04 am

The Solaris does that already, Jimmy.

jb

Post Reply