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Path: utzoo!linus!philabs!prls!amdimage!amdcad!cae780!weitek!mahar
From: mahar@weitek.UUCP (mahar)
Newsgroups: net.music.synth,net.games.video
Subject: Re: Marble Madness & FM Music Synthesis
Message-ID: <267@weitek.UUCP>
Date: Wed, 11-Sep-85 16:25:43 EDT
Article-I.D.: weitek.267
Posted: Wed Sep 11 16:25:43 1985
Date-Received: Sat, 14-Sep-85 01:44:38 EDT
References: <2614@ihnss.UUCP>
Organization: Weitek Corp. Sunnyvale Ca.
Lines: 36
Xref: linus net.music.synth:473 net.games.video:464
Summary: marble madness answers

In article <2614@ihnss.UUCP>, knudsen@ihnss.UUCP writes:
> I've concluded that a large part of the MM game's music
> is Frequency Modulation generated.  Some questions:
> 
> (1) Do you agree?
Yep. All system I and system II game systems use a Yamaha FM sound
chip set as well as one of the old "Pokey" sound generators.
Paper Boy also has this chip set and has similar quality sounds.
> (2) Someone posted a rumor that the MM arcade game uses the
>     Amiga's sound chip set.  If so, does that imply that Amiga
>     supports digital FM synthesis?  Wow!  Actually, an LSI
>     FM chip should be pretty easy to build.
Your right. FM chips are not that hard to build. However, Yamaha
has the basic patent on FM sound generation. Atari's lawyers
didn't want to fight it so they just bought the chips from Yamaha.
> (3) What techniques ARE used in the newer built-in home computer
>     sound chips?  The old Atari & Commodore chips were mostly
>     analog, right?  Are the new ones using digital filtering,'
>     AM, FM, or just good old waveform scanning with ADSR?
The Atari 800 and 400 as well as most of their coin-op video
games used a Pokey chip (or several). This is just a counter which
generates square waves at different frequencies. For sound effects,
the Pokey has a Poly counter which is a cheap random number generator
for white noise.
> (4) Has anyone ever managed to record the whole "Marble Madness
>     Suite," so to speak?  I'd pay money to get it all on a 45.
Call Atari at (408)747-2700 and ask them. Or, talk to your local
arcade operator. They can put the game in selftest mode and you can
listen to any of the sounds on command.
> (5) Another possibility for the M.Madness game:  Maybe the whole
> sound track was just prerecorded in a  studio , non-real-time,
> with a 16-track tape, etc., and we're hearing just a CD Disk!
> Makes sense: sometimes the game "loses" the music and takes a couple
> seconds to pick up the track again.
Nope. The losses of sound are cause by a communication break down
between the main processor and the processor controlling the sounds.