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Re: more on Kyma.....



This is a posting of  Jim Coker <jcoker@interaccess.com> in '97. I just
stumbeled over it and liked it and since we had talk about this going, I
repost it.


>> Jim answered me:
>> >In reference to Matthias' questions, most parameters on sound
>> >objects (such as delay times, frequency settings, filter bandwidth
>> >and frequency) are controllable in real time, and without glitches.
>> >Put an lfo on a short delay, and you get a flanger. (Delay lengths can
>> >be specified in a number of ways, such as in seconds, or samples,
>> >or relative to something else)  Control signals can come from midi,
>> >or all sorts of other things, frequency trackers, envelope followers,
>> >other audio signals, or signals built by processing other signals.
>> >When I was there, a Peavey PC1600 fader box (16 programmable
>> >midi faders and assorted buttons) was set up to
>> >control sound parameters. This is what I used during the looping
>> >test (no foot controller available).
>>
>> I see... but this I can do on my PCM80, as long as its just controlling
>> parameters of a delay.
>> I was thinking about the loop specific functions like Tap, Multiply, 
>Undo,
>> or rather sampler type functions like restarting the actual loop or
>> changing to another loop and so on. Probably those functions will have 
>to
>> be created and I wondered how difficult this might be.
>
>Well, there's no tap tempo control that comes with the unit (I asked),
>but
>I don't think it would be difficult to build one.  As far as the
>echoplex-type
>functions go, it depends on your goal.  If you want to duplicate the
>interface
>of an echoplex, you can probably do it, but I can't say how difficult it
>would
>be, and I don't think it would be the best way to approach loop
>programming
>with Kyma.  Since you can have a large number of loops and samplers
>running
>at once, and there are numerous controls available on them, some of the
>metaphors
>that apply with the echoplex don't make much sense.  For example,
>multiply
>on the echoplex affects the original loop, whereas on Kyma, I would be
>more
>likely to achive a similar result by adding a new, concurrent loop whose
>time is a multiple of the first.  This would leave the original loop
>available
>for individual processing.  Of course, everyone has their own preference
>about
>how such features should be configured, but a big part of Kyma is that
>the
>user has many options on how to organize things.
>
>>
>> >Another nice patch involved a "harmonic resonator", a special
>> >kind of filter that resonates at a given pitch and all it's
>> >harmonics.
>>
>> also available on PCM70/80
>>
>> >Probably the most unique capabilities of the system revolve around
>> >it's analysis and resynthesis capabilities.  Their latest software
>> >version comes w/ a configureable vocoder w/ up to 70 filter bands.
>> >In addition to real time vocoding, you can analyize a sample
>> >(drums, vocals and animal sounds work best, due to their widely
>> >varying formants) to build a time-varying filter bank, and then use
>> >this filter bank to process a live signal.
>>  ...
>>
>> >For really hard-core stuff, you can use an FFT analysis to convert
>> >the signal from the time domain into the freqency domain, and do
>> >processing there (such as stretching or scaling harmonics, pitch
>> >and time shifting, etc), and then resynthesize the result using
>> >an oscillator bank.  This is the approach used by Digital Performer
>> >1.7 and others to do pitch shifting w/o ugly artifacts.  Kyma
>> >can do this in real time, minus a 1/4sec delay due to FFT
>> >windowing issues
>>
>> Interesting. This could certainly be used to colour and modulate loops. 
>And
>> in this case, the 250ms delay (thats a lot!) could be hidden somehow.
>
>The delay is intrinsic to all FFT algorithms.  The processing occurs by
>taking short samples (called windows) of the input, and doing the FFT
>on each window.  Longer windows give more accurate frequency results,
>shorter ones give a better indication of when events occur in the
>signal.
>The windowing is what causes the delay.  I do think it is adjustable, so
>shorter delays can be traded for some accuracy.
>(caveat: That's a very short and imprecise description of a complex
>signal processing task)
>
>
>> >The only dissapointment I had was with the frequency tracker.
>> >It works amazingly well w/ vocals, but didn't do so great on
>> >a guitar.  The response time was at least as good as a Roland
>> >GI-10 midi converter and it did track vibrato and
>> ...
>> > One big change that would make
>> >it better would be to use hexaphonic input a-la GK2, which would
>> >restrict the pitch guessing range, and avoid multi-string noises.
>>
>> Did you play monophonic for this test, or is it even able to detect 
>chords
>> of a monophonic guitar?!?
>
>The tracker can't handle chords, that is truly a difficult task.  It is
>discussed in the Curtis Roads book I mentioned earlier (as is the FFT
>stuff).
>
>>
>> >Currently Kyma only has 2 inputs and 2 outputs, but they are working
>> >on increasing this.  They get many requests to increase the
>> >number of outputs, but Kurt said that this was the first time they
>> >had a solid reason for having multiple inputs, ...
>>
>> Ahh... we will end up making our own VGx, more serious, with all in it!
>>
>> >Kyma can run simutaneously w/ a
>> >sequencer or MAX on a modest MAC or PC.  Symbolic Sound is also
>> >working on a PC-card interface so you can use Kyma w/ a laptop.
>>
>> Does it also work without any computer, on stage?
>
>Nope, the computer is the controller, where all patches are stored and
>other important things happen. It also, obviously, lowers the price of
>the
>Capybara, which has no front panel controls.  There is a midi-map
>function
>so you can use program changes to load new sounds.
>
>The "stuck-to-a-computer" issue is one the Sym. Sound is aware of.  They
>had said that at AES some engineers from Eventide had asked if they'd
>had people complain about requiring the computer.  They are working on a
>PC card for laptops, so that makes it a bit less of a problem.  The way
>I see it is that they leverage so many capabilities from the computer
>that
>the restriction is well-justified.
>
>> Did you check the reverb sounds? If the KYMA replaces two Plexes and my 
>two
>> Lexicons, its not that expensive any more!
>
>I don't know of any serious reverb programs that come with the unit, but
>it has Delays, Comb Filters and such that can be used to build reverbs.
>There are some general reverb algorithms covered in signal processing
>publications, but if you're looking to replace the reverb in a PCM80,
>its not gonna happen easily.
>
>This brings up the issue of what Kyma is all about. The fx boxes from
>Lexicon,
>Eventide and others come with great programs that are ready-to-use
>and are targeted for music production, but even though they have
>relatively
>flexible programming options, their limitations are rigid: They have a
>fixed
>processing & memory capacity (for both delays and programs), a limited
>number of processing algorithms (i.e. chorus, flange, pitch shift,
>reverb), and limited
>number of ways to combine those algorithms.  Kyma is an open-ended box,
>it is
>what the user makes of it.  Symbolic Sound provides a number of useful
>processing algorithms, software to combine them in new and interesting
>ways, many intriguing
>and instructive example programs, and ongoing software and hardware
>updates that avoid obsolecence.
>
>It blurs the distinction between synthesizer, effects processor, hard
>disk
>recorder, sampler and sequencer.  It is a little bit of all these
>things, but
>by combining them all it becomes something different entirely.  The
>first
>demonstration Carla showed me was a piece that she had created for Kyma.
>The complex
>program turned the Capybara into an instrument, in that it created
>synthesized
>sounds, an effects processor, in that it processed her voice in real
>time, a
>sampler, as it played & modified sounds from disk, a sequencer, in that
>sounds
>were layered and ordered by program events, and a real-time studio or
>composition tool, in that the operation of all these processes were
>interrelated,
>and she was able to control the whole process through vocal inflections
>and
>midi sliders.
>
>Kyma is a solution for those who have
>become frustrated with the limitations of the equipment
>they are working with, and want to create an instrument of their own. It
>will not
>likely replace a Lexicon reverb unit in anyone's rack, but reveberant
>sounds
>built using it can be new and unique. It may not harmonize as
>effortlessly as
>an Eventide, but it has numerous tools for modifying pitch.  It is a
>toolset
>for creating music, and thus the user has both the exciting and
>somewhat daunting task of making something out of it.
>
>
>
>jim





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