additive

[Jim Johnson]

>well, thats not what they are teaching in engineering school these days!
>They say that (loosely quoted from textbook) "Any sound can be broken up
>into its harmonic series using fourier analysis. Once these basic
>frequencies and amplitudes are known, then, all that needs to be done to
>replicate the original sound is to do a time domain analysis of the
>amplitude changes of each of the various harmonics." 

Yeah, that's what they said when I was in engineering school 20 years ago,
too. This is the kind of oversimplification that is rampant in engineering
texts - as exemplified by the statement "any sound can be broken into its
harmonic series"... As has been discussed on the list, not all sounds
consist only of integer harmonics. Furthermore, no musical instrument
produces a single sound - there is an incredible range of variability in
the sound produced by any single instrument.

And to top it off - the statement had to do with modular and FM synths, not
Fourier (additive) synthesis. Yes, we can talk about modulars that can do
128 harmonics, with separate envelopes and phase control for each partial -
but there is no such instrument. Nor is it possible to build one, in
practical terms.

>BUT, it IS possible.. there used to be a program for the atari ST that
>would take a sampled sound and break it down using fourier analysis and
>turn it into sysex and send it to the ol Kawai K5.. I believe it worked
>on the dx7 too..mind you, the replication of the samples were often
>terrible, but some were very close.

That's digital resynthesis, not modular synthesis.

>Actually, the first generation attempt was the mellotron (sampling) and
>FM additive was the second.
>But, now Im sounding like a know it all dickhead, sooo..  :))

I suppose I should have counted the Mellotron in there, but that was such a
strange and unique instrument.... But what is "FM additive"? 

Jim Johnson 
Metaphoric Software
-------------------
Makers of Techno Toys
Software for Electronic Music
http://www.technotoys.com
info at technotoys.com



*********** REPLY SEPARATOR ***********

On 8/12/98, at 9:35 PM, cyborg0 at globaleyes.net wrote: 

>Jim Johnson wrote:
>> 
>> >theoretcly any acostic sound can be made in a modular
>> >ether by addtive or FM but this is hard to be made.
>> 
>> No, it's not theoretically possible to do that.
>
>
>well, thats not what they are teaching in engineering school these days!
>They say that (loosely quoted from textbook) "Any sound can be broken up
>into its harmonic series using fourier analysis. Once these basic
>frequencies and amplitudes are known, then, all that needs to be done to
>replicate the original sound is to do a time domain analysis of the
>amplitude changes of each of the various harmonics." 
>> 
>> >so my qustion is can i play a acostic instrument like a
>> >pino or violin or other in to a mic and then in to a scope
>> >and see its waveshape and envelope and then calculaite
>> >this data and creat the same sound on a modular ?
>> 
>> I've never heard of such a tool. I doubt that it is possible.
>
>BUT, it IS possible.. there used to be a program for the atari ST that
>would take a sampled sound and break it down using fourier analysis and
>turn it into sysex and send it to the ol Kawai K5.. I believe it worked
>on the dx7 too..mind you, the replication of the samples were often
>terrible, but some were very close.
>
>Actually, the first generation attempt was the mellotron (sampling) and
>FM additive was the second.
>But, now Im sounding like a know it all dickhead, sooo..  :))
>
>whatever!
>rob