From claire_trikes_aust@iprimus.com.au Tue Nov 04 23:15:37 2003
Subject:Re: Drawbar Registrations - HUH?!

Kevin,
I don't think you are on quite the right track here, dumbing down the power
and elegance of the drawbars. Even if one doesn't get too technnical (and I
know you can) a little knowledge can help a great deal.

The drawbars are arranged in as a kind of analog or equivalent to the
components of a tone (fundamental and harmonics). The whole numbers reflect
harmonics that would be an octave apart (eg 16, 8, 4, 2 1). An octave is a
frequency ration of 2:1 and is generated by halving the length of a pipe or
string for example. Using these harmonics gives a sweet tone and setting
them up with a decreasing intensity gives a traditional 'clean' flute
character. Eg 00 8402 000 Remember this as being a step pattern for nice
flutes (forget the numbers - remember the shape.)

The traditional Diapason tone has richer harmonics (bring in some fifths and
thirds but lower intensity, IE Gs and Es if you are playing a C note).
Think of this shape as a sawtooth. The shape is more important than the
numbers but to give you an idea try 00 8776 543.

Reeds (such as clarinet, sax etc) have an emphasis on odd harmonics. Think
triangle shape (with the point, pointing towards you). Once again the
overall drawbar shape is more important than the numbers but listen to say
00 467543. A special case is a clarinet being a good example of a strong
fundamental with decreasing strength of odd harmonics. (It produces an
almost perfect square wave. You can get your sine wave Hammond generator to
make a semblance of square waves by simply adding the harmonics
appropriately. Knowing this, it is easy to set up say 00 8050 300. Try
it low down on the keyboard with a little vibrato and no leslie and you may
be suprised how close it sounds to a real clarinet.

The shape to remember for strings is curved. Try say 00 4555 554 to get the
idea.

Forget the numbers - remember the shape. And you don't need to know that
you are actually rembering the shape of the intensity of the harmonic
fourier analysis.

My apologies to the more knowledgble people on this list as I know that this
subject is much more complex (interesting and beautiful in its own way) but
I have tried to make these concepts accessible for a situation where there
is a risk of "overanalysis from a purely engineering standpoint without any
useful counterpart in a live musical context."

There is considerable beauty and sophistication in the nature of sound, the
mathematics that describe it and the complexity and wonder of our musical
scales. But each to their own, twiddling to get what sound you like without
seeing a least some part of the amazing structure of it all, is perfectly OK
(but it does seem like a bit of a waste).

Best regards,
Claire


> The footages in drawbars have their roots in the pipe organ. Those
> of us who are drawbar organ players know this, but before getting too
> far up on my soapbox, the questions below don't really have any
> merit, for instance "which drawbar is middle C?". I don't know any
> of the answers to these questions below and haven't for the 29 years
> I've been playing probably because they aren't really relevant to the
> organist's playing style and mostly because I would rather have fun
> playing the music than analyzing the sound.
>
> There is a particular KEY on the keyboard which is middle C, but a
> drawbar is simply a tone-coloring device based on pipe organ theory.
> Read about pipe organs and you will know what drawbars are for. Sit
> down with a Hammond or clone and LISTEN with your musical ears and
> adjust till you hear what it is you want and tweak from there.
>
> As far as discussions of fundamentals and harmonics - those can all
> be answered from pipe organ references and an understanding of how
> additive synthesis works.
>
> Most of these other questions are just overanalysis from a purely
> engineering standpoint without any useful counterpart in a live
> musical context.
>
> Sit down at a Hammond or Clone and play. If you like what you hear,
> stick with it, or tweak it to your liking and let the music flow from
> your soul.
>
> Many of the questions you have will be answered from within rather
> than from analysis.
>
> Regards,
> Kevin