Tuning Spectra program.

Somebody asked me a question stemming from a discussion of the instrument
spectra I posted a few days ago. I suspect that some of the rest of you
might want to ponder the following comments as well.



> Differences in timbre are accounted for by the attack transient (which is
> what makes realtime pitch detection such a bear) and the relative
> strengths of harmonics in the sound. Correct?

For a given tone from that instrument, yes, those are definitely the main
factors.

But I think that there are two factors that are equally important: The
patterns of timbres (as defined by those attributes) across the entire
instrument, and how the instrument is performed.

Along the first lines - or perhaps both lines - I have recently become
aware of a curious consideration with regard to synthesizing purely "fantasy"
timbres - timbres not intended to resemble anything we're particularly
familiar with: It's a whole lot more difficult to do than most of us
realize. Synthesizer programmers tend to think of the various instrumental
timbres as pillars of recognizability in a vast sea of timbral possibilities.

I've found that the opposite is much closer to the truth: Viewed as
individual tones, instrumental timbres are *anything but* narrow pillars in
timbral space. There is instead a huge amount of variation in what we would
call, for example, a clarinet tone, and that varied gamut overlaps profusely
with flute, saxophone, trumpet, and even oboe tones.

So our ears use several other cues to identify an instrument, not the
least of which is its timbral register content. As an example, the fact that
saxophones have an especially prominent dulling of its timbre upon crossing
from notated C# to D (second space to second line) is a very big clue to our
ears that we're hearing a saxophone. An instrument losing high-harmonic
content in their upper registers is a pretty strong clue that you're more
likely listening to a wind instrument than a string instrument.

A closely-related, but probably even more important characteristic in
identifying an instrument, is its range. Probably the deadest of giveaways
to suggest that you're listening to an electronic simulation of an instrument
rather than the proverbial real thing is playing a note out of its range,
especially below its range, since the lower-end of most instruments' range is
more clearly defined than the upper end. This is one of the very few places
where a pianist actually has a disadvantage in composition: They're used to
a continuous gamut spanning almost our entire range of hearing. Instrumental
range limitations seem difficult to accept, whereas to performers of
orchestral instruments, that's just a normal fact of life.

Another related rare case where pianists seem to be at a disadvantage in
composition, is in the concept of transposing instruments. I remember it
once taking about five minutes to explain the concept to one of the best
musicians - a lifetime pianist - in one of my ear-training classes. In her
defense, I should point out that she understood what I was describing almost
immediately, but promptly dismissed that idea as almost surely a
misunderstanding. When she finally realized that she did indeed understand
my suggestion correctly the first time, she spent a few minutes convinced
that I kidding.

Thankfully only occasionally, I sometimes hear another rather amusing dead
giveaway that you're actually using a sampled simulation of an instrument:
Failure to stick to a fixed complement of instrument parts. I have heard, in
what was intended as an orchestral or small-ensemble simulation, duet of ...
flutes, say ... suddenly blossom into four or five just for couple notes or
so. You can semiarbitrarily add notes to fill in harmony at will on a
keyboard instrument, but there's just no way that a symphony orchestra, or
most other ensembles, will hire three or four extra flutists just to play a
note or two here and there! You have to think in terms of a predefined
combination of monophonic parts from the start.

But anyway, another consideration that can make a lot of difference in
deciding what instrument we're listening to is how we play the instrument.
An extreme case of this is perhaps the Rhodes-style electric piano. At its
theoretical basis, there's no reason at all why it should sound even mildly
reminiscent of a real piano: As I understand it, they use - essentially -
tuning forks, whereas real pianos of course use courses of strings. But even
though piano strings produce very complex overtone structures and tuning
forks put out almost exact sinewaves, the fact that it's being played
stylistically similarly with a piano reminds us so much of a piano that we're
fooled into thinking that it sounds kind of like a real piano.

Granted, another big part of that electric piano illusion is due to the
fact that the two instruments' attack and envelope characteristics are
similar. Even still though, a surprising amount of what we identify as
characteristic of a particular instrument are embodied in playing style.
Often these are things that go easily unnoticed: As another example,
classical brass playing style doesn't allow for much vibrato. The same is
true for classical clarinet style, but vibrato is fine for other woodwinds.
The result is that a saxophone can sound surprisingly brass-like by simply
playing a bright tone with no vibrato. Since saxophone technique normally
uses plenty of vibrato, when you forego it, the effect starts to remind us
more of a brass instrument.

The really unfortunate part of all this is that there's not very much room
for interpretation in our audience's ears. You might be tempted to say,
"hey, I don't have to stick with exact simulations of acoustic instruments;
I'd like to instead use slight variations on them, like a violin without
vibrato so as not to pollute the beatlessness of just intonation". I
reeeeeeally don't recommend that approach! People are extremely picky about
such things. If a tone you create sounds sufficiently like a violin, they'll
immediately say "AAAAACCCCK, where's the vibrato?!", and the result will be
something that they don't like.

In summary then, I've found that, in coming up with electronic "fantasy
sounds" it's a lot more difficult than it might seem to *NOT* give people the
impression of it being a well-known instrument. And if you invoke that
impression, you pretty much need to "go all the way" and reproduce that
instrument sound perfectly, or some people will get upset.

------------------------------

End of TUNING Digest 1491
*************************

I've just read through a copy of _Lou Harrison: Composing a World_ by Let=
a
Miller and Frederic Lieberman (Oxford University Press, 1998) and recomme=
nd
it -- and the accompanying audio cd -- without reservations.

The authors have made an elegant and entertaining read through the life a=
nd
works of this unique figure in the world's musical lanscape. They have
fearless tackled the most complex subjects central Mr. Harrison's: whethe=
r
dealing with musical intonation, politics, the tangled mess of his score
catalog, Harrison's relationship to traditional musics, or to the sometim=
es
devisive history of gamelan in North America, Miller and Lieberman manage=

to be clear, thoughtful, and often provocative. (Okay - I do have a
reservation: once again the primacy of Surinamese gamelan in the new worl=
d
is left out, an error that Mr. H. would surely not have made!).

The chapter 'Assembling the Pieces' appears to me to be the center of the=

book, a study of a composer at work. Such a key to how Harrison applies h=
is
wide musical resources will be especially useful in further studies of
Harrison's work, particularly in sorting out Harrison's relationship to
Javanese gamelan music, where he both revels in ahistoricity and
experiments within a framework of contraints that is, on its own terms,
conservative. In fact, such attributes have long been part of his work, a=
nd
the extension to a gamelan or gamelan-like instrumentarium is a developme=
nt
of his own technical and aesthetic concerns and not a wholesale
appropriation of resources. Harrison's music is too often mistaken for a
naive species of orientalism; such a confusion reflects a fundamental
misunderstanding of 'where the action is' in the music and this book is a=

first corrective in what I hope will be continued further study.

May I add that it's a special delight to see this book come from two UCSC=

faculty members. During my undergraduate days there, too long ago, an
interest in Mr. H.'s music was decidedly NOT part of the accepted academi=
c
discourse. Harrison's few visits to the UCSC campus were hit and run
events, avoided by the music faculty as one would avoid a hurricane, and
were in themselves a powerful corrective to the different brand of musica=
l
conservatism then prevailing.

Daniel Wolf
Frankfurt =