Question about pitch modulation

[Charlie Firpo]

Hello!

I created a simple 1 osc patch with an envelope modulating the pitch of a pulse osc. I noticed some small detune differences between two instances with the same patch. The first instance was without any modulation, and the second had full pitch modulation with the modulating envelope sustain level to max (and attack, Decay, release was untouched. I thought that the pitch modulation was a 100% 1 oct up when using an envelope? But i noticed some small detune between them? It's not like the end of the World, but i was just curious if there's an other way to get the pitch to track 100%

[Charlie Firpo]

I almost get Dizzy Reading my own text ;-)1. Here's a step by step. Create a simple one oscillator patch with no modulation at all. Make two instances and play them side by side with the same note. (sounds identical)

2. Modulate the pitch of one of the instances with an envelope. Set the pitch modulation to max, and the sustain level to max. Now when i play them side by side (with the same note) i can hear some detuning going on. You know.. sometimes im tired of my dog ears.

So the question is, aren't the pitch modulation supposed to track 100%?

Thanks!

[MadGav]

Hi Charlie,

Thinking through this from memory I think the modulated Osc would be a little flat? If the pitch at the start/end of the envelope will not be held when audible then tuning the osc to bring the sustained pitch into tune would be the "hack"? Unfortunately this is the kind of thing that if changed would mess up existing patches so think it will have to be as it is!

Martin

[Charlie Firpo]

Thanks for the answer Martin! Now i can finally sleep at night No worries, there's almost Always a workaround in Vaz! Now back to making Music with this wonderful synth!

[elecdrum]

Every instrument or system has its quirks...

I often encounter similar "problems", starting with the filters' lack of a precalibrated tracking input, over tracking problems due to signal loss when using switches between different pitch sources, up to assymetries in summing which depend on how many modules a signal goes through before reaching the respective mixing module. However, I think it's fun to work around that kind of stuff, and it does add some charm to VAZ Modular - sort of like voltage drops in an analog modular system when using long cables.

That said, the addition of linear (read: pitch stable) FM in version 3 was welcome and does make a certain class of sounds easier to tune and get to track. Just wish that the analog waveforms and the filters (!) were available with linear FM, too (there have been some analog modules which were claimed to provide this, but I haven't tested them yet).

[MadGav]

Hi Elecdrum,

Linear FM is certainly something I'm interested in (the only analogue option I can patch is feeding an external Osc to my MS-20). Linear FM for a filter is quite rare, the only Euro option I can think of is the A-111-5 aka Dark Energy module and I suppose other 80s CEM-based synths?