I swore you use to be able to enter things like “C3” into any parameter right click menu and VCV would convert it into 1V/Oct standard. Its not working for me right now. Am I miss remembering that? Does it work for anyone else?
it only works for frequency input - not voltage.
I asked VCV a few days ago:
"Just writing to let you know, the entry in the changelog you referred to is correct, but the automatic conversion is to Hz, not V, causing the issue you note with VCV Seq 3, but this allows you to type in note names into frequency parameters.
However, we have added the ability in the next version of Rack to type “ftov(c3)” (without the quotation marks) which will convert the c3 into the correct voltage (in this example, -1). Paul Gatt VCV"
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Coming from more of a MIDI knowledge background it struck me offhand as odd to have C3 as -1, so I took a look at the Voltage Standards, which I find is a bit under-specified.
It says C4 should be a VOct knob at its default position. This implies that the default position is centered, and VOct signals are bipolar. It also makes no mention of the range to be expected (although the arithmetically-inclined can calculate it).
Aside: The MIDI spec makes no reference to a notation standard, so we have a situation where different device makers have chosen different frequencies for “Middle C” and varying octave numbering.
I didn’t find links to the “Eurorack standards” mentioned by the Rack docs, so I did a little research. Drilling down from the Eurorack - Wikipedia page leads to the original descriptive docs from Doepfer here:
Technical Details A-100 (doepfer.de)
It’s a good (brief) read.
In a previous life, I spent quite a bit of time working with International standards (ISO, ITU, internet RFCS) and detailed formal technical specifications. So my expectations for what “standard” is has needed a little adjustment in the context of (Euro)Rack ;-).
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There’s a few standards outlined here < Scientific pitch notation - Wikipedia> and some websites claim that there is an iso standard also but the iso website doesn’t have it. The standards focus around c4=261=midi 60. It the daws and devices are all over the place naming 261hz c as c3, 4 and 5 depending on the manufacturer. In surge this upset people so much that we have an option.
The voltage standard though seems pretty clear mathematically. It says f=f0 2^v where f0 is 261hz / middle c. You can offer an offset but your zero offset should follow that. So 0v is c4, 1v c5 etc…
(This all assumes 12tet and halberstadt layout etc)
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ftov(c3) makes sense, but seems awkward for a UI. Simply v(c3), or better yet, vc3 works well for me.
ftov(x) could be reserved for entering actual frequencies, with note letter notation being a convenient alias. So ftov(c3) and ftov(130.81) would be equivalent. But v(c3) or vc3 would only work with named notes, and could convert directly to voltage, without considering frequency. Simply subtract 4 from the octave designator, and add a fixed voltage for each of the 12 named note values (well, more than 12 with the enharmonic sharps/flats).
I suppose I should submit this request to support.
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I also sent a note to Support. I really think we need a simpler way to do ftov(note). I suggested a format like “C5v”, where putting a v at the end indicates the output should be volts instead of Hz.
In modular everything is voltage, so using Hz doesn’t really make sense for sequencers. But this feature would make it so so much easier to program sequencers to do different pitches.
It never hurts to ask, but I assume the ship has sailed on this one.
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Cool news! VCV implemented our feature request in the new V2.6.3 
The way to use it is to simply put a “v” after the note. So like “C4v” will return 0V, and “C5v” will return 1V.
If you want to convert a specific Hz value, say 500Hz, into Volts you still need to use the old format “ftov(500)”, which makes sense to me.
The new feature is super handy for sequencers and modules (like mine!) that use V/oct rather than Hz. I can tell I’ll be using it a lot.
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For an Arrange devotee, hallelujah!!
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