# Synth parameters and correspondence tables



## cedricm (Apr 20, 2022)

Trying to understand a synth in depth is highly frustrating: most user guides do not detail parameters at all: neither their unit nor their range nor the correspondence between value and printed value.

Example: Diva's cutoff of the VCF ladder: printed numbers go from 0 to 10, which isn't the same as the Minimoog D it emulates, and values from 30 to 150. No unit stated.
What's more, it clearly does not work as a standard low pass filter: with a low value enough, most notes of a keyboard won't be heard with a standard 24 dB LP. With Diva, you can play all the notes, as high as you want.

More generally, most VSTi synths do not mean the same by the same parameter: Sustain will be a percentage corresponding to the level in one, but a duration in another. Detune will go from -30 to 30 in one (unit unknown), and 0 to 100 % in another.

So I'm looking for:
- A table of correspondence between the parameters of various virtual synths
- A compendium of description of parameters way beyond what user guides offer.

Do you know of any such resources?


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## rezoneight (Apr 21, 2022)

Have not heard of such a thing. Just as a point of reference though even on the Model D the printed value on the panel doesn't match at all the freq range that the dial controls. I'ts just -5 to +5 on the panel but the actual range is 10Hz to 20KHz. Oddly on The Legend from Synapse, which models the Minimoog, the filter is 25Hz to 28KHz but at least thats printed on the panel unlike the real thing.

Think you've have to contact the support of u-He to find out what those values are for Diva as they aren't in the manual


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## Pier (Apr 21, 2022)

Honestly I think seeing the actual values might be more of a distraction than anything of value. Some synths give you exact values (Vital IIRC) but in practice I haven't found this to be of much help. I mean, you can just use your ears.

The only case where I've really needed to see values is when I want to keytrack a filter cutoff to actual notes, but that's easy enough to do with a tunning plugin or some analyzer.

In Zebra if you set a filter cutoff to a value of 1 and keytrack to the max value, the cutoff will be very close to the notes you play on the keyboard. I'm not 100% sure this applies to all Zebra filters though.


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## cedricm (Apr 21, 2022)

Pier said:


> Honestly I think seeing the actual values might be more of a distraction than anything of value. Some synths give you exact values (Vital IIRC) but in practice I haven't found this to be of much help. I mean, you can just use your ears.
> 
> The only case where I've really needed to see values is when I want to keytrack a filter cutoff to actual notes, but that's easy enough to do with a tunning plugin or some analyzer.
> 
> In Zebra if you set a filter cutoff to a value of 1 and keytrack to the max value, the cutoff will be very close to the notes you play on the keyboard. I'm not 100% sure this applies to all filters though.


Well, numerical values and their ranges, units and meanings can be of great help.

First to understand what's going on.
Second when trying to recreate a sound with a different synth.

Even for as basic a thing as ADR, it takes many trials and errors to find out what the ADSR values are.


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## Pier (Apr 21, 2022)

cedricm said:


> Well, numerical values and their ranges, units and meanings can be of great help.
> 
> First to understand what's going on.
> Second when trying to recreate a sound with a different synth.
> ...


You don't understand what's going on by listening to the sound and the effects of the parameters?

(I'm not being sarcastic)

And even if you knew the envelope release is 1500ms that doesn't tell you much. Envelopes have different curves (exponential, log, linear, etc) so most of the audible change might happen in 500ms or 1200ms. And I'm guessing analog modeled envelopes do not behave linearly (the curve changes depending on the value of the parameter).

And then you have to consider envelope modulation (eg: changing the release length with the velocity)...


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## rezoneight (Apr 21, 2022)

I'm with Pier. For me I just twiddle until it sounds good. I don't care so much about the numbers. Have never found that the numbers help me understand any of that better than my ears. YMMV obviously.


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## b_elliott (Apr 22, 2022)

I am with Pier and others on "values". Although what follows is not synth related, it has overlap.
For example: an EQ cheatsheet I looked over noted a bass drum has its slap at 4kHz. 
I put up a BD sample, dialed my EQ to 4k but got nothing. When I instead used the solo feature of Neutron3 EQ I found the "slap" is actually a "click" @3.1K. Even my first idea of what to listen for was miles off.

Takeaways: 1. The #s on charts/tables/guides can help or lie.
2. Use your ears. 
3. Better yet, train ears and get a sense of what sound you'd expect to hear at 100hz or 1000 or 10kHz; or, in your synth studies, what you'd expect to hear when you move the LFO rate knob....
Hope this helps.
Bill


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## rezoneight (Apr 22, 2022)

Good points Bill, thanks for that as it was something I hadn't considered.

I think you're scenario is exactly why many "newer" EQing tools like the Pro-Q from FabFilter have graphs that are showing the real-time view of the freq spectrum.


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## Snoobydoobydoo (Apr 25, 2022)

Exact values? Those are tricky. 
Humans are no bipedal binary patchgenerators. If you start thinking in values, the machine will win. Think in degrees as the naval captains did ago.
The compass in your heart will guide you avoiding that forsaken siren island (FM) without even looking on the map (manual) a toothless gramp gave you in the harbor.
Its all lies, do what your ears tell your heart please.


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## Paul_xyz (May 3, 2022)

cedricm said:


> Example: Diva's cutoff of the VCF ladder: printed numbers go from 0 to 10, which isn't the same as the Minimoog D it emulates, and values from 30 to 150. No unit stated.
> What's more, it clearly does not work as a standard low pass filter: with a low value enough, most notes of a keyboard won't be heard with a standard 24 dB LP. With Diva, you can play all the notes, as high as you want.


Not sure what you mean by that - the -24dB ladder in diva goes effectively silent as the cutoff knob is lowered to zero eg presets > templates > INIT minimono - hold note and move cutoff to zero

Are you sure you didn't have some "keyfollow" enabled when you had it playing across the keyboard?


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## muratkayi (May 3, 2022)

I'm all for using your ears. There is a saying "the eye guesses while the ear measures". Its ability to gauge dynamics (when talking about envelopes, e.g.) or even frequency range is unsurpassed. Try to tune two oscillators by putting two physical (IRL) knobs in the same position by eyesight and then do the same using your ears...

But!

If you want in depth analysis, why not route your internal audio into VCV rack and use an Oscilloscope or do something similar with other tools for audio analysis? You can see if the curve of an envelope is linear, logarithmic or exponential in the scope easily.

I had rather just play the synth and make music, but if you love a rational approach an in-depth analytical study has to be seen through.


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## cedricm (May 4, 2022)

I'm all for using ears too but having usable numbers can greatly accelerate the process. 

Having spent days switching between Ableton and Studio One, Falcon, Diva, Ableton Wavetable, Serum and other synths, there are so many things to take into account that any number one can rely on helps make sense of a patch. I'm quite happy with the progress and have pages of notes on the differences between synths.


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## cedricm (May 4, 2022)

Paul_xyz said:


> Not sure what you mean by that - the -24dB ladder in diva goes effectively silent as the cutoff knob is lowered to zero eg presets > templates > INIT minimono - hold note and move cutoff to zero
> 
> Are you sure you didn't have some "keyfollow" enabled when you had it playing across the keyboard?


Yep, I do need to check this.


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## muratkayi (May 4, 2022)

Hey, would you be up for sharing some of these notes? I have to admit that dedicated analytical approach sounds fascinating


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## Snoobydoobydoo (May 5, 2022)

Oh and if its about a uhe synth, the guy can be asked there. They are happy people.


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## Pier (Jun 1, 2022)

These past weeks I've been using PhasePlant more compared to Zebra which has reminded me of this thread.

PhasePlant is extremely informative about everything you're doing. For example, you add a modulation and it tells you the range on which the modulation is acting, whether that is some filter cutoff value in Hz or some pitch value in notes.

I'm guessing this is the type of information @cedricm wants from a synth?

It might be that I'm just too used to U-He synths but personally I wish I could tone down all the visual info that PhasePlant throws at me. I admit sometimes it is useful, but more often than not I find it distracting. I really don't want to be bombarded with endless values and information all the time.


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## jkeller51 (Jun 1, 2022)

Pier said:


> These past weeks I've been using PhasePlant more compared to Zebra which has reminded me of this thread.
> 
> PhasePlant is extremely informative about everything you're doing. For example, you add a modulation and it tells you the range on which the modulation is acting, whether that is some filter cutoff value in Hz or some pitch value in notes.
> 
> ...


In the spirit of balance, I like having real units in advanced synths like Falcon, Pigments, & Phase Plant. Sometimes I know exactly what frequency I want a filter at, and I appreciate synths that allow me to just punch it in. This is even more true for pitch & amplitude. I want to be able to punch in -6 dB if I want the gain cut in half. If I want to jump an octave, I should be able to type 1 octave, or 12 semitones. Don't make me fiddle with knobs if I already know what I want.


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## hanysz (Jun 12, 2022)

I'm surprised at all the negativity here. The human brain can handle more than one mode of thought! We can be precise and analytical and measured, and also spontaneous, creative and artistic. Having access to real numbers isn't going to kill your music making! Just don't look at the numbers on your "spontaneous" days, but they'll still be around when you want them.

Visual artists figured out vanishing point perspective more than half a millenium ago, and there are plenty of paintings where someone measured everything up, put pencil lines in the calculated places, then created beautiful art on top of it. Performing musicians have been using metronomes and tuners for a few decades now, and I'm sure we're better off with than without. So why not have some numbers on filter cutoffs and envelope times?

Here endeth the rant.

As for softsynths, Surge and Vital display quite a lot of information on the screen, and Zebra explains most of the parameter ranges in the manual. I'm not sure why the Diva manual is so much less detailed. For other synths, I think you have to reverse engineer what you need. Put some noise through a filter, crank the resonance, and run it through a tuner to see what frequency you got. Put an envelope on a burst of noise, record the output, then you can see the stages visually and measure them.

I'm not aware of anyone who's published a concordance. Maybe if you start one, others can add to it?


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