
How Oldschool Sound/Music worked [video] - Audiophilip
https://www.youtube.com/watch?v=q_3d1x2VPxk
======
0xcde4c3db
Good video, but it seems to somewhat conflate FM synths (e.g. Yamaha YM3812,
YM2610, YM2151) with primitive envelope+counter-based PSGs (e.g. General
Instrument AY-3-8910/Yamaha YM2149, Ricoh/Nintendo 2A03, Texas Instruments
SN76489). I'd argue that the character of these two classes is substantially
different. The PSGs are much more built around pure waveforms (for certain
interpretations of "pure waveforms" that include pseudorandom noise), while
the FM synths tend to be built around sets of parameters that produce sounds
almost, but not quite, entirely unlike traditional musical instruments.

Another interesting bit of trivia is that the Yamaha "FM" synth chips were
actually based on phase modulation (PM) rather than frequency modulation (FM).
The abstract math can be transformed back and forth between the two, but the
PM formulation accumulates less error when directly expressed in digital
hardware.

The Commodore SID is arguably in a class of its own and probably can't be
fully explained without some kind of textbook-length exegesis.

edited to add: samples to try to demonstrate what the heck I'm blabbing about
with the difference between PSG and FM:

PSG:
[https://www.youtube.com/watch?v=uyMKWJ5e1kg](https://www.youtube.com/watch?v=uyMKWJ5e1kg)
The Legend of Zelda - Main Theme (Koji Kondo; 2A03)

FM:
[https://www.youtube.com/watch?v=JWPNxSD9YNY](https://www.youtube.com/watch?v=JWPNxSD9YNY)
\- The Revenge of Shinobi: The Shinobi (Yuzo Koshiro; YM2612)

~~~
chipsy
There are a lot of aspects of the phenomenon of "chiptune sound" that aren't
given much due. For example, early arcade hardware was more prone to using
analog components - think of the rumbling explosions of games like Space
Invaders, or the 6-voice subtractive synth used in Sente games[0], reused by
Sequential Circuits as a standalone synth[1]. The Atari 8-bit chips(both TIA
and POKEY) contained "distortion" effects (based on a variable-length LFSR)
that could be used for both noise and guitar-like tonal timbres[2]. The true
successor to the SID is the Ensoniq DOC used in the Apple IIGS[3] and
SQ-80[4], but it gets little attention. And lastly a number of later chips,
including the Game Boy, had a low-res wavetable on at least one voice, which
allowed for some more timbre options(albeit 90% of the time it was a
sawtooth)[5].

[0]
[https://www.youtube.com/watch?v=9xCiOXQJO18](https://www.youtube.com/watch?v=9xCiOXQJO18)
(MAME emulates this chip but does a terrible job)

[1] [https://www.youtube.com/watch?v=Wa-
Cwn4po40](https://www.youtube.com/watch?v=Wa-Cwn4po40)

[2]
[https://www.youtube.com/watch?v=JDeV7wrB2c0](https://www.youtube.com/watch?v=JDeV7wrB2c0)

[3]
[https://www.youtube.com/watch?v=WujTzBCRBAY](https://www.youtube.com/watch?v=WujTzBCRBAY)

[4]
[https://www.youtube.com/watch?v=5y8fNnDJUx0](https://www.youtube.com/watch?v=5y8fNnDJUx0)

[5]
[https://www.youtube.com/watch?v=caz21XapSiA&list=PL3B271CECB...](https://www.youtube.com/watch?v=caz21XapSiA&list=PL3B271CECB53A0AD2&index=11)

