Theo Verelst Local Diary Page 81
I've ditched the usual header for the
moment, I think it doesn't help much anyhow.
This page is copyrighted by me, and may be read and transferred by any
means only as a whole and including the references to me. I
guess that's normal, the writer can chose that of course, maybe
Ill make some creative commons stuff one day, of course I have
made Free and Open Source software and even hardware designs available!
page is under construction, so check back later, too.
July 16, 21:16, 2009
A forum about Kurzweil
Error in voice rendering what happens with my nine kayer sound
June 2009 - 12:21 AM
This nice sounding 9 layer soundfrom here
Called AnaFMSmpljoy2c because it combines two layer osc analog, 6
operator equiv FM and 2 layers of sampled EP, and it uses effects like
narrow stereo chorus for the analog part. Playing it as a program at
times gives me errors like here though:
see the 16 bit wav or mp3 examples.
Having the latest OS installed that's not good, or is there something
the matter with the sound (or should I try to reinstall?)!
Posted 06 July 2009 - 03:03 AM
yesterday made an experimental sound from the Horowitz piano sound of
the presets, changing the tuning slightly from e.g. velocity, and I
trimmed the filters and the envelopes, for purposes of preventing
annoying harmonics in the high range. Don't worry if you don't really
hear them: not many people are currently into trying out transient
harmonic distortion from combined samples, but I try out the sound as
good as I can, and prefer in this case (on stage without my system that
is quite different, and that *is* what the PC3 is prepared for, too) a
'hifi' type of test, with my high quality monitoring, confirmed by
headphones, various other speakers, indirect headphones, and with or
without external DA converter.
I was after some more expression freedom as far as the samples would
permit that, coming from (in this case not to advanced chosen) chords
played with notes with varying velocity. On of the original (Ray)
Kurzweil issues I'm sure has been (when was it, I recall reading about
it in 85 or so) to not just squeeze the samples in a small amount of
memory but making them and the playback engine work good with all kinds
of combinations of tones, velocities, possible crossfades and timbre
crosses and such, interesting material, and a reason why software
samplers with a boatload of samples can still sound sterile and
hopelessly unharmonic, to the point of horrible I've regularly notices.
Of course the Kurzweil is in the world top of piano sound reproducing
machines, and I'm glad to play with one though naturally (I made and
demonstrated a physical modeling guitar algorithm half decade ago) if
I'd have money I'd want also to try the new Roland PM one, where the
samples can't get in the way because there aren't any, really!
To add to the niceness and liveliness an warmth of the non-trivial kind
I've tried to use some of the effects available like woodenizer and
small cabinet. Don't forget like some others have said to add effects
to your liking, there are many great sounding ones and when dosed rigth
they work very well with the sounds, which is a compliment (because
that's far from easy in the digital domain to achieve). A favorite of
mine is to feel in another world by putting an open stage reverb on
used on a extensive quadro setup, using the extra output pair of the
Well, just to make clear a few of the issues I punched on Rosegarden,
used the pC3 'board' a little and recorded straight from digital out at
48kS/s (24 bit) possibly (hopefully) without any sample conversion and
I put the master section and digital volume control on 'defeat'.
Consequence was of course a sound at about -12 dB, so the mp3 sounds a
(16 bits stereo, from 32 floats)
I guess one could comment on wether such a type of piano sound, which
I'm sure isn't really in the presets, is more a musical type of sound
that certain people might look. I am SURE it isn't more realistic in
some important measures, no mistake about that. Oh I play piano from
Gospel to Funk/Jazz Fusion since 80 or so, the piece for me is no
'piece the resistance', just something to try the sound out.
Posted 14 July 2009 - 11:35 PM
A thirty band analog
type equalizer sure is cool, but I'd prefer a
sound which is naturally good. I suppose still that in a certain
measure (checking FFT or other spectrograms ?) the preset sounds a re
accurate, I only made comments about sample cross modulation (it sound
like to me) type of distortion in the higher range, and am aware of the
difference between a live performance oriented sound and a horowith
recording on Chesky or so.
I edited the above sound more, and changed the effect chain, and think
the result is improved to start sounding like an actual grand in a
space, depending on amplification and volume. It's for download on my Wiki
those who want to try.
I must compliment on the Kurzweil sample-path because it allows what
I've done with the sound, which is *very* far form trivial...
July 2009 - 01:16 AM
JohnKeeL, on 11 July 2009 - 11:31 PM, said:
Ok here´s a quick question, i have the
following interface: MOTU 828Mk3 + MOTU 8Pre
What´s the best way to connect the PC3 to it for optimal
A quick answer: I think the question is important because norms change
some ways since decades ago but it isn't always clear how signals go.
In short I'd think you probably would want to use a digital input from
your unit. I don;t own a Motu, I use A Lexicon Omega unit already for
years and using quite extensive quality monitoring I'd say in these
times of the return of high signal quality (the 'normal' HiFi adagium
as in neutral is best) the extra DA conversion in the PC3 followed by
an extra AD conversion in your interface is not very beneficial.
Probably noise can be excellent (I know I can easy work over hundred dB
and more) so that's great, especially when you use balanced cables, and
the overall signal will probably still be pretty and good, but those
converters, and their assumptions (filters, sampling type) and the fact
they'll be not running at exactly the same sampling frequency can cause
hard to define (altough) measurable signal deviations, which probably
are nicer prevented by using the good digital output from the Kurzweil,
setting it to the right frequency on the master page.
I get the best results doing this, even better then taking the analog
output of the PC3 and pluggin directly in my (very high q) preamp: a
tos cable to the lexicon digital in. For recording you may want to
check the interface you use follows the incoming digital audio signal
sample for sample, so that you don't do a (possibly only small) sample
rate adaptation, because that is also going to sound less optimal. That
also holds for the computer software you use o record with: preferably
make it slurp the incoming samples without changing them (sync source
to the tos input).
In the context of plugging in and playing: take a normal mono jack
cord, plug into some at least half-decent keyboard amp, and the sound
will be more than fine. No misunderstanding, I'm talking about trying
to get the best (preferably neutral) result, not getting a very good
result, than most decent things will work fine.
Adding a preamp when you use analog outputs will possibly stop your AD
converter input from blowing up ( a possible studio reason) add of
course the character of the preamp to the signal (analog warmth is not
likely but possibly the result), create some distortion or even
clipping (probably not desirable), be an impedance matter (can the
output drive the inputs with no preamp (most probably the pC3 can).
Because the PC3 of course has a DA converter in its analog output path
some more things will happen when you add or do not add preamp buffers.
It could be the preamp acts as a sampling residu filter. Otherwise it
can be the high frequencies present in the output will upset the preamp
and create annaying types of distortion: trying out I guess.
Balanced has of course the major advantage of (besides from creating a
little more headroom) preventing hum and other disturbances, so it's
great the Kurz has 4 balanced outputs. In these days of switched
supplies and DA converted sounds, there are all kinds of high frequency
issues with signal grounds, so in extreme cases, when the grounding
circuit in the balancer can't keep up, you can try using unbalanced
signals if you have strange 50/60/100/120 HZ related transient
distortions or worse (like tones in the signal radio type things). An
unbalanced inoput will mostly have at least one internal stage less
than it's balanced counterpart, which may prevent distortion (just try,
no need to bother much).
For the people having made remarks about the sounds: it seems to me
that it is somewhat comparable as with serious quality bluray players:
the built in high number of bits converters are great. Period. But for
the perfectionists probably things can be said, which could simply be
there are imperfection in them, possibly also numerically. I don't
recall (or maybe they aren't there) the exact specs of the Kurzes'
output, but it may be that on very good audio systems this is an
subject. Trying the digital out is interesting in that sense.
Since there are probably 'things about sampling' and of course the on
this forum mentioned 'preparation for the live stage' things going on
with the sound, it could in principle be that the extra transients from
you preamp will sound wonderfull to your ears, or that this so and so
mixer preamp is actually what was used for sound making monitoring: so
by all means use the same
03 July 2009 - 09:33 PM
Euh, like I communicated last week slightly about with SoundTower:
considering the PC3 (Maybe the prophet 8 for instance requires a serial
number for the software to work/download? I got to buy 'my' PC after I
could play around with the ST SW, actually) in this case is free as in
free of charge what is the reason to keep (maybe some parts) it Closed
Source, which even in Windows-World nowadays seems hardly a must.
I'd imagine the ownership of the software ideas and probably the
control of the software and users dynasty are at stake, to make an
honest start of a discussion about the subject, as far as people are
interested, and of course not in the "Free Beer" sense primarily, let's
say I'd not even mind paying money and signing a non-disclosure
agreement to get a Midi-def. But it's not like ST needs a patent from
the sw as it is, I think it is almost a direct programming of the same
info avialable from the PC3 screen, except some saving and of course a
large overview of the parameters and a midi link, which isn't always
the best idea (try removing some layers from a many layer sound with
the sw, the PC dsoes it much faster, read: in interaction time, in my
case). Maybe the internals of the Kurzweils need protection from
vandalism or simply from copying, I don't know. The samples, the ideas
in the DSP signal path and so on: could be.
I mean, unix was first open source and half commercial and later on
often commercial and now again in Linux incarnation Open Source. I
don't claim it in my perspective currently is great to make open source
software, I guess I's like to make money, but those concepts are in the
free west not intertwined in such fashion. And I feel much better
working on Open Source ideas, regularly, and feel soooo much better on
my Fedora with Xwindow variations and all kinds of legal open software
Long the the brave and the free or is it...
Feel free to kick the idea in some other forum of course,
but with a link please...
Posted 14 July 2009 -
Stefan Lindmark, on 06 July 2009 - 11:14 PM, said:
The download link is at the bottom of the page. No
need to register to download if there's a server problem with the form.
Yeah, thanks. As I indicated somewhere, I had the software already, it
actually was fellow reason for the instrument purchase, so I knew that,
and must say I was very glad about. I just thought maybe something is
wrong and thought I´d enter the data: it´s being asked for
so maybe you
guys keep statistics or something. Or maybe it´s a Linux Firefox
that may need attention or just a spur of the moment, I don´t
For a hobby research project along the lines of
(see first subchapter)
mathematical formula rendering , also mentioned here:
of wave formulas with BWise
I´d like to do some MIDI patch
programming with the PC3.
For an impression: my server allows for making math sounds all
automatically, see this example page: http://www.theover.org/Max
Needless to say I´d like to transfer (or ´map´) math
to begin with complex additive synthesis sounds like above) to VAST,
but preferably automatically (by hand is a lot of work and my software
) can vary rapidly
create graphs and formulas from them and allow changes too).
And an Example song with sampled drum (Made on Linux with FOS), 1 FM
piano and the mathematical sounds targeted for the PC3 (I might try to
VASTify it by hand but if I don´t belief I can do automatic MIDI
programming in the overseeable future my motivation is lower) panned
hard left and right (melody and bass): h.mp3
The melody is the
solution formula of a differential equation (see
for wav version).
I would find it great to take a wave, map it to an number of in this
case VAST operators of good quality, and automatically play such sounds
on the Kurzweil synth, and be able to play with it with much polyphony
and like with samples and modulations.
When I in general asked for more (self) programming over MIDI a little
while ago (in fact to map a general graph automatically to a number of
cascaded layers), Mark from Soundtower suggested:
"If you have an idea for the HD V.A.S.T editing you can share it with
me: bitmap would be the best. I check it and if it is very good we may
tailor it in the editor. It will have your signature on it but it will
require a fraction of your time...."
Clearly that isn´t so easy in the case I´m interested in.
Well, to whoever will either state official company policy ("Njet") or
hopefully understand I want to built in like my own stereo system in a
nice car I bought and would like to know the wiring: I don´t mind
risking a reboot or so, any form of info (a small part of source code,
or a scan of napkin with the main parameters, or is DSP code being
programmed?) to be able to set actual parameters myself over midi, like
on the pages on the display of the machine from a program or script I
make, is welcome. I mean somebody somewhere has something of a list of
those things or soundtower couldn´t have made software, unless
the Soundtower editor and the internal sound editor contains a DSP
assembler, but hey that´d be cool too, unless of course that is
I´d probably share it and possibly in Open Source form as it is,
if that is a valid community oriented consideration.
Long live free Midi!
Posted Yesterday, 03:42 PM
Gildabass, on 15 July 2009 - 11:20 AM, said:
! theo ! i didn't get half of what you do, but it is incredible ! is it
music ? is it physics ? I really love the concept of creating melody
with mathematical formulas…
It's clearly music from I suppose a singular Swedish original source,
being made by using a MIDI song file I found on the internet ("Hasta
Manana midi" in Google), which sounded cool, played by rosegarden on
Linux with a soundcanvas in Fluidsynth (or Qsynth) for drums, a Hexter
DX-7 simulation program connected for the piano chords, and two
programs of mine being mixed in for the bass and drum sounds. In fact
those programs contained a waveform from adding sine waves with
exponential decay, but different time constant for each sine wave, and
in accurate mathematical ways and 64 bit sample computations, and the
other a 'symbolically' solved differential equation with almost a sine
wave as a solution, also sample-approximated very accurately, and I
might have mixed in a bit of LADSPA reverb over the mix, I would have
to look that up (the 'diary' or more like 'reporting' page I mentioned
probably has some more info).
Those mathematics for the bass and solo can directly be correlated with
physical resonances of respectively the electronics of a number of
tuned but different damped oscillations, and a simple system which
resonates in a particular way which leads to the used differential
equation, so your right: it's close to physically makable systems.
Samples and DSP easily make waves which are not relatable to actual
physical systems, because the resonating strings or air columns in the
sampled instruments cannot be detuned (even a bit) without losing their
sense of correct dimensions, it is as if the sounding board and harp of
the piano for instance are shrunk or expanded in size. And when using
seperate samples per key and velocity, the non-linearity of the
resonating boards and string influencing each other (especially for
interesting complicated Jazz-chords) and the non-sampleability (for the
mathematically oriented: Impulse responses demand the same starting
conditions for each impulse convolution to be correct, as soon as a
wave 'stands' or bounces in the space, that condition is already
theoretically violated) of the resonances of the air in the sounding
space makes the result per definition also somewhat until quite far
away from the real thing, even on a good monitoring system.
I suppose the melody could be considered a very basic but fundamental
solution of the Physical Modeling kind, but pretty accurately so. I did
some real PM program and computations too ( see here
and demo sound file
), live demonstrated on a large european Open Source conference, but
that's harder, and the mathematics of such simulations are very (to do
good: extremely) hard.
I'd like to try making the type of simulation work on my PC3, but I
don't know if that is possible with the dynamic V.A.S.T. architecture,
I'd have to make coupled harmonic oscillators, of at least 64 or so on
a row, and probably even coupling them in the cascade direction and
then around is hard, but maybe some of it can work already, I need to
try. It takes a lot of computations, but the Kurzweil has some pretty
strong DSP going on.
So the above is like a compromise: mathematical waves can often be
mapped on the VAST arch, but I cannot at the moment do that
automatically because the MIDI exclusive (or what is it) protocol isn't
'available'. I don't know if that will turn out to be official company
policy (would be a disappointment, I mean even most consumer HiFi
systems used to come with diagrams) we'll have to wait and see. Maybe
they don't want a whole miriad of open source or worse private close
source software things messing with the machine (would create more
hard-to solve support problems, possibly).
I'm glad you like the type of sound, I think that's why I made mention
Both the bass and melody sound are probably directly from my mathematical function sound example page
and are on
my mental list to implement on the PC3, which should work.
Mathematical sounds ported to the PC3
Making songs with a new instrument
I tried my self made / adapted sounds in a song, with global multiband
compression, made of four tracks, recorded digitally over TOS
44.1kHz/24 bits, in like an hour.
(12.5 MB , CD-Q) kurznewtv1
[.mp3] (2.3 MB, 320kbps)
kurznewtv1_1 [.mp3] (1.4
kurznewtv1_2 [.mp3] (1.4
MB) 256 kb/s