ETD Displays

Ron Nossaman RNossaman@KSCABLE.com
Tue, 27 Feb 2001 16:35:09 -0600


>In case you dont understand..... take A4.... play it and use the puters
>controls to stop the dancing dial. Now play A5 and tune it till that same
>dancing dial stops. You have now exactly matched whatever A4 partial the etd
>was set for in the first place. You can of course choose on purpose what
>partial to do this for..
>
>or..... you can even, assuming you have a mulitpartial display, look at more
>then one partial at a time.
>
>shhessshhh..
>
>--
>Richard Brekne

I did read the post, and I didn't pull the trigger. I'm trying to introduce
a little fact based practicality into this thread. The only difference
between referencing one note, storing the information and reading another
note for comparison is that both sets of partials don't have to be
separated during processing. All the rest of the finding of partials,
determining their actual frequencies and such will still have to be done in
real time if it's to be of any use for tuning. Given the choice, I would
certainly prefer to be shown what I was doing at the time I was doing it
rather than being shown what I should have done after I was finished.
Dean's product gives you partials information doesn't it, albeit not
graphically and certainly not the information you want? Does it do it in
real time? No? Why do you suppose that is? I suspect it was done to annoy
you by making you wait for it. Just having one chosen partial to look at
and compare with your already REFERENCED NOTE doesn't strike me as good for
much anyway without seeing the entire partial structure of both notes at
once. Even at that, I'm not so sure it would be of much use in tuning
except as visual verification of the virtual untunability of certain scales.

In the interest of focus, let's assume some programmer out there was smart
enough to actually understand what you were talking about and attempted to
produce it for you. Let's also assume that he's using hardware so fast it
computes all the required information instantly. Now that all this
information is available, how exactly do you get the required precision of
visual indication by a sliding partial ladder against your already
REFERENCED one? If you were to chose an octave A3 to A4, for instance for
comparison. How many partials would you think were necessary - 3, 4, 8, 12?
How would you show the fine differences in partial alignment on 10 partials
over 2000hz apart on a 600x800 computer display? A set of scaled up
verniers for each set of coincident partials would do the trick, if you
could keep track of what was what. But that's just more dancing needles,
and too darned many. With all that jittering around of all these magnified
frequency coincidents, that ought to be pretty impressive, not to mention
headache inducing. When a visual indication of pitch proximities ranging
from 0.001hz to, say, 10hz diversion range is required, you just about need
both a coarse and fine scale for a quick and easy visual proportional
indicator of each partial's pitch. Logarithmic scales would display the
information with fewer displays, but are harder to read at a glance. How
handy would that be? I admit it would be interesting, but I seriously
question it's value for tuning - even when it becomes possible.    


All this can be done much more quickly in dedicated hardware than it can in
software, and can quite probably be done nearly immediately by simply
throwing the required number of shekels at the proper individual or
organization. The hardware is already out there.


Ron N


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