#1

Quick question, are the CV voltages precise enough to use in calibrating other modules? Clouds needs a 1V & 3V input in the calibration, and I was wondering if TT would work well in this instance?

#2

You’ll get within a couple millivolts so I’d say it’s probably as good as any other accessibly priced options.

#3

FWIW, I’ve used it for exactly that purpose and it seems to have worked perfectly.

#4

@Galapagoose , @chrisharrisx cool, that’s good to know, thanks!

#5

Firstly, apologies if I’m overthinking this stuff and apologies to @tehn for bumping another thread that might give the impression that teletype is anything other than miraculous, these questions are from a place of curiosity rather than a pedantic pursuit of perfect voltages. Teletype’s versatility is what I always wanted from eurorack (hence expect lots of modules up for sale imminently).
This is more of a general question about tuning analogue oscillators but, since I just received a teletype and am curious about it’s role in this case, I figured this thread was a good place to start. With all the analogue oscillators I’ve tried there is a jump in pitch when having a dummy cable in the v/o input and then plugging it into a sequencer at 0v (Rene, Metropolis etc), I’m curious about why this is as I’ve had digital oscillators that don’t do this, I guess it has something to do with power supplies and grounding and lots of other complicated stuff.
In terms of using teletype to calibrate an oscillator (mangrove in this case), if I’m going to be starting at 0V (or as close as teletype is to 0) and adding 2V, does it matter that all 4 teletype cv outs at 0v make this jump differently when plugged into v/o? they vary over a range of about 12 ct on a tuner (cv1 will do 12ct, cv2 will do 24ct, cv3 will do 18ct, cv4 will do 15ct). As long as I use only one of the outs to do the calibration this shouldn’t be an issue right?
Also, another general question about calibration in this way, is there any benefit to starting at, say 1V and going to 3V over the 0V to 2V thing I’m talking about here (possibly negating any problems with the Dummy cable to 0V output jump if this has any relevance)?
BTW if I’m remembering correctly Mangrove and Teletype are giving 12ct tuning divergence over a couple of Octaves which works out at around half a cent per semitone. Seems pretty damn good.

#6

I think you’re already working around the issue by the sounds of it. In this case, the Mangrove is responsible for the majority of the pitch shift, not the teletype (though there are tiny offsets on the TT outs). This is a due to a difference in internal ground potentials that I didn’t understand 3 years ago when I designed the module.

In general it’s not a problem, but you need to do the calibration with the cable attached (0v is CV 0 V 0 not cable-unplugged). The only thing that matters for calibrating the module is the difference between the voltages. V1 to V3 would work too, but it will make no difference. Which TT output doesn’t matter, any slight difference of offset will be represented at the higher voltage output as well.

In practice, if you’re trying to do tightly tuned sequences, i recommend you tune & prepare your patch with the volt/octave source pre-patched.

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#7

Hey, thanks. Good to know the voltage offsets are represented at higher voltages. Loving TT and Just Type btw. Those 2 and walk have been the most Eurorack fun I’ve had. So deep with the run modes too.