Super-sensitive synths, etc.

> [Gerald Eskelin wrote...]

>>In regard to super-sensitive synths, I'm almost afraid to ask........what
>>synth?

And Carl Lumma generously responded:
>
> There are others here far more knowledgeable on this subject than I. But I
> gather that there are two parts to the question:
>
> 1. How much tuning resolution can the synth address -- how much does it
> even attempt to produce?
>
> 2. How closely does the sound played actually match the note the synth is
> trying to play.
>
> To answer the first part, you've got to decide how you want to send the
> tuning information to the synth -- pitch bend or sysex? Pitch bend works
> on all synths, and the resolution is potentially very great, but most
> synths ignore at least some of the pitch bend resolution. I don't know
> which ones are good at this. Usually, working with pitch bends is awkward
> -- to my knowledge, all the musicians who have successfully used pitch
> bends for tuning have controlled their synth from a PC, using software they
wrote.
>
> The far more popular and easier option is sysex. To find out about the
> sysex tuning capability of a synth, I always consult the microtonal
> synthesis web site...
>
> http://home.att.net/~microtonal/
>
> The two most flexible designs are the Kurzweil K2000/K2500/K2600, and the
> Emu Audity 2000 / Proteus 2000. The Kurzweil units accept tuning data in
> 1-cent increments, and the Emu units accept data in 1.56-cent increments.
>
> Then there is Kyma, from Symbolic Sound. It requires a PC, and costs about
> $3300 for an entry unit. It allows arbitrary precision of tuning data.

> Answering the second part is more tricky. There was a discussion here a
> while back about wavetable synths delivering poor and inconsistent
> accuracy. I wasn't involved in this discussion, so I can't tell you much
> about it. But to my knowledge, the most accurate synth as far as producing
> what it's trying to produce (that's the second part), is again Kyma.
> Supposedly, it's never off by more than 0.0026Hz.

That price tag is what I feared. I'll put my money, such as it is, on human
ears. They're handier, a lot less expensive, and amazingly accurate given
sufficient experience.

>>And even more reluctant to get into "log-accuracy." The phrase "over
>>my head" comes to mind.
>
> Well, cents are a logarithmic measure of frequency. You know, to add two
> ratios (like 5/4 and 5/3) you multiply them (25/12). But to add to
> intervals in cents (386 and 884), you add them (1270). Deal is, if a synth
> is off by 1 cent, that could be 0.064 hertz at A=110, or it could be 1.017
> hertz at A=1760. So if you're mis-tuning a just ratio way down low in the
> frequency range by 1 cent, you'll have to listen much longer to hear a beat
> than you would mistuning by 1 cent in the upper range. If a synth was off
> by a certain number of hertz, that would be many cents down low, but few
> cents up high. Most synths are accurate in cents as far as what they're
> trying to do (first part), and in hertz as far as what they're actually
> doing (second part). Follow?

Actually, yes.

>>May I assume that your input here, Carl, is to improve my faulty concept
>>(which it does) of the limitations of MIDI and not to stifle my complaints
>>about the inadequacy of 100 cent increments to match what the ear can hear?
>
> I'm not sure. Keep in mind that 100-cent increments is 12tET. I took you
> to mean 1-cent increments.

Of course.

> When tuning notes of the same timbre, in the
> most sensitive range of the ear, differences of less than a cent in a
> harmony can be heard, as piano tuners prove every day. But to hear
> mistuning at this level requires a trained ear, and careful listening. In
> a musical situation, such small mistunings come across as a _subtle_ change
> in timbre. Nevertheless, it is one which piano lovers and audiophiles can
> hear -- it has been said that a good tuning "brings the piano to life".

I am beginning to realize that my penchant for "pure" tunings, likely
fostered by my affection for barbershop and vocal jazz, may not be the ideal
for all musical styles. An opera chorus, for example, might be less exciting
if pure tunings were the top priority (although I generally have wished for
better phrasing and vowel focus from most of those I have heard).

> I would encourage you to discover exactly what the accuracy of the synth is
> question was, and to qualify your statements by answering questions like,
>
> What type of music was I listening to?
> What limit was the harmony?
> What timbre was being used?
> How did the mis-tuning sound to me?
> Was this a blind test?

Thank you very much, Carl, and I appreciate the time and effort it took for
your response.

Jerry