MOTM

My ever haphazardly-cast interest-of-the-week has settled upon FM-- and the
kind thereof, the DX-7.  Does anyone have or know of a DX-7 architecture
diagram or description?  Among other things, I'm wondering about / hoping
for basic block architecture, the potential oscillator interoperability
(i.e., FM routing), modulation, and EG functionality.

Anyone have any insight as to why greater-than-2-operator FM synthesis never
left Yamaha, aside from Clavia's peek in the Nord Lead 3?  Or are there
synths aside from the DX family and the recent FS1R and DX200 that do
intensive FM?

I are in need of edumacation.  :)  Thanks!

--PBr

The thing you need to stare at is the diagram that is on the top of the DX7.  You
might be able to search the Yamaha site for the docs or search around sonic-state or
harmony-central for FM sites.  There used to be lots of them.  The main thing to
remember is that all of the "oscillators" in the DX series produced only sine waves.
 Later systems tried other waveforms.  These "operators", as they are called, can be
either a sound generator (carrier) or a modulator.  Each operator has a pitch EG and
an amplitude EG.  The EGs have 4 levels and 4 rates, much like the UEG.  There is
also a scaling processor that can be applied to operators and EGs.  The "algorithm"
is the interconnection of the operators as carriers and modulators.

From a historical perspective, Buchla really made the first linear FM oscillators
but it was Chowning at Stanford who really worked it out and Yamaha vigorously
defended their licensed or purchased patents.

   Eric   


--- "Brousseau, Paul E (Paul)" <noise@...> wrote:
> My ever haphazardly-cast interest-of-the-week has settled upon FM-- and the
> kind thereof, the DX-7.  Does anyone have or know of a DX-7 architecture
> diagram or description?  Among other things, I'm wondering about / hoping
> for basic block architecture, the potential oscillator interoperability
> (i.e., FM routing), modulation, and EG functionality.
> 
> Anyone have any insight as to why greater-than-2-operator FM synthesis never
> left Yamaha, aside from Clavia's peek in the Nord Lead 3?  Or are there
> synths aside from the DX family and the recent FS1R and DX200 that do
> intensive FM?
> 
> I are in need of edumacation.  :)  Thanks!
> 
> --PBr
> 
> 
> 
>  
> 
> Your use of Yahoo! Groups is subject to http://docs.yahoo.com/info/terms/ 
> 
> 


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In a message dated 8/1/01 6:35:32 PM, noise@... writes:

<<  Or are there synths aside from the DX family and the recent FS1R and 
DX200 that do intensive FM? >>

On a related note, I'm wondering if the DX200 and the PLG150-DX cards are 
true FM synths or do they just emulate FM synthesis?  Not sure that makes any 
sense now that I think about it...

Ivan

hello all,

there's a retro review of the DX7 in the august issue of sound on sound - if
i remembere correctly, there's also a functional diagram and a bit on FM
synthesis

cheers
paul b

On Wed, 1 Aug 2001, Brousseau, Paul E (Paul) wrote:

> My ever haphazardly-cast interest-of-the-week has settled upon FM-- and the
> kind thereof, the DX-7.  Does anyone have or know of a DX-7 architecture
> diagram or description?  Among other things, I'm wondering about / hoping
> for basic block architecture, the potential oscillator interoperability
> (i.e., FM routing), modulation, and EG functionality.

  Go to Dave Benson's DX7 site:

ftp://byrd.math.uga.edu/pub/html/dx7.html

  All sorts of goodies there.  I should scan and send Dave the "DX7
Technical Analysis" guide.  It is filled with ridiculous little comic
strip characters that are illustrating things like the EG chip handing off
envelope data to the operator chip.

> Anyone have any insight as to why greater-than-2-operator FM synthesis
> never left Yamaha, aside from Clavia's peek in the Nord Lead 3?  Or
> are there synths aside from the DX family and the recent FS1R and
> DX200 that do intensive FM?

  I think the Yamaha patent on the technology was granted in 1976 or
thereabouts. Anyone could use it, they just had to pay Yamaha a royalty.
This patent expired 17 years later.

  The first commercial FM synth was the Synclavier, actually, predating
the Yamaha GS1 by a few years.  The Synclavier was 8-bit FM, whereas the
GS and DX engines were 12-bit plus 4-bit compander.

Crow

/**/

Ah yes indeed...  unfortunately, SOS always shows up a month late in the
states.  The July issue is on the magazine stands now.  Looks like I've got
something to look forward to (as if the ongoing Synth Secrets wasn't
enough!).

Thanks to everyone for their input!

--PBr

-----Original Message-----
From: sikorsky [mailto:vulture.squadron@...]
Sent: Thursday, August 02, 2001 1:24 AM
To: MOTM List
Subject: Re: [motm] Yet more OT: Yamaha DX-7 architecture diagram?


hello all,

there's a retro review of the DX7 in the august issue of sound on sound - if
i remembere correctly, there's also a functional diagram and a bit on FM
synthesis

Hey Folks,
I guess this isn't 100% OT since the water loop was created using several
MOTM modules.

I need some help testing a game w/ cookie detection on mac/pc platforms. You
will need the latest macromedia shockwave plug-in.

I need some volunteers to do the following:

1. go to this URL
http://www.octanegames.com/test_streaming/sports_fishing.html

stream in the game WITHOUT registering first(1.4megs)  A not registered
screen should come up, let me know if it doesn't. Before the actual game
starts there is another menu that comes up allowing you to choose your lake,
there is a black message window under the menu area that should say whether
you are registered or not.  Let me know what it says and what browser you
are using.

2. Play the game through without registering and let me know what the
message window says on the game over screen.

3. Register to win
http://www.octanegames.com/register.cgi

4. Go back to:
http://www.octanegames.com/test_streaming/sports_fishing.html

and RELOAD the shockwave game and let it stream in again.  This time the
message window should say "You are all set."

5.  After you are registered try to get a high score.

6. Email me with any feedback or bug reports subject: FISHING GAME
Please include platform(including how much ram you have) and browser brand
and version number.

FYI all high scores will be cleared tomorrow, we will start the PS2 giveaway
contest starts next week.

Regards,
Don