Moog Theremini!

now this  cat is a dead pussy  and now starts to smell funny. but thanks for the final insight.

?  maybe a small hope to get something more out of "it" : http://numericalaudio.com/theremidi/#

it says 'comig soon'. so stay tuned.

Well,

To wrap up one more time, Moog got back to me and they are working on improvements. They have had requests for pitch preview, looking at the linearity issue, are looking at providing an editor, so I'm going to keep an optimistic view that some future firmware releases will improve the instrument.

As for the biggest issue, this comparison of the pitch distance versus pitch of my Theremini vs. my Etherwave Plus says it all. That's it for me on the Theremini until a firmware release comes out.

Rich

Rich

Hmmm..

The Theremini  looks damn linear  over about 7" (4 octaves) .. Now if they could just tip that angle a bit ;-) .. Sadly, thats not so easy to do..

Must admit I am quite surprised though - from the last set of (CV) results I never expected to see more than a couple or 3 linear octaves, but if the graph is accurate, each linear octave is compressed into less than 2" so are probably unplayable anyway, except perhaps for midgets with really short arms and small hands ;-)

Fred.

To be fair, I should say it does change from calibration to calibration. This is a worst case I saw on one calibration from the higest octave down. So it could be very sensitive to how you initially do their calibration routine. Also the last octave on the Theremini not shown here is about double the distance (C2-to-C3 in this case).

I'm not 100% positive my unit is behaving right as I'm not sure why its playing an octave higher than the tuner says. Need to see what Moog says about that.

They did say it behaves strangely when you have an Etherwave near it (which I didn't in this case).

All,

Support got back to me and Moog is looking into a number of things and could have some exciting upgrades in store for the Theremini - so let's wait a bit and see what develops. I think it's way to early to give up on this box. The kitty may only be in a state of stasis. Let's all see what develops. My unit may in fact have an issue with the pitch display vs. output they are looking into. 

Rich

By the way for anyone who has bought a Theremini and has the linearity issues I have, I found a way to bring it more in line with my Etherwave. I'm short so this likely makes my issues greater. Try calibrating the instrument way further back than you normally do. When I stand back a foot or two more than I could possibly play from, the calibration routine seems to scale the thing much more in line with my Etherwave. You only lose a couple pitches you can't get to at the bottom range this way. I might give this a shot for a while to see if it can be used as portable practice instrument (my main goal for it right now). Not ideal, but maybe acceptable until firmware updates come out.

Rich

And perhaps some of you will be interested in the spectral comparison of A440 on the Theremini vs. the factory shipped Etherwave Plus with Tone and Wave knobs all the way to the right - the setting that gives the more complex harmonic structure ("more stringy" if you will). The Theremini obviously is based on a very similar spectral signature (of even and odd harmonics). You could probably guess if asked which is the digital representation and which is analog. The filled in areas are the instantaneous plot of when the screen snapshot was taken and the upper line is the peak value. By the way this is a free VST plugin from Blue Cat Audio.

Sorry,

That image looked ok before I posted it, but it got clipped. Here is is scaled down:

Hi Rich,

If we presume the theremini is repeating a sample recorded from the ew, then the harmonics being the same is little surprise..

But the question for me comes (and this applies to all wave-table replications, not just the theremini) down to whether the analogue instruments harmonics change as a function of pitch (and IMO the critical aspect is whether the harmonics are different when pitch is changing, particularly if changing rapidly), and whether the wave table instrument behaves in a similar manner.

This kind of analysis is much more difficult to undertake (and its probably impossible to do on an instrument with long latency, because change of pitch [delta] is restricted)

In my view, "deadness" of sound may be a function of lack of the natural distortion one gets when gliding quickly between pitches - IF a cycle of of an audio waveform is always completed before the next updated cycle is started, this behavior is entirely unnatural - because in nature, as pitch changes in a continuous manner, the waveform distorts - and this same behavior is replicated with theremins and analogue synthesisers.

One other matter (and there probably is some morphing mechanism in the theremini to do this - I dont know) is about the waveforms one gets from adjusting the EW tone controls - do you have a similar ability on the theremini? and do the harmonics for different settings equate to those on the EW?

The interesting thing to me about this subject is not the theremini per-se, but the whole issue of generating audio from any digital theremin.. I am not yet convinced that digital audio generation is up to the job - digital is fine for recording and playback, and ok for generating tones on instruments with fixed pitch intervals - but I am not convinced that it is yet up to generating audio for instruments where pitch is free to move between intervals, and to do so sometimes quite quickly... Instruments like analogue synthesisers and theremins.

Fred.