Path: utzoo!utgpu!news-server.csri.toronto.edu!clyde.concordia.ca!uunet!snorkelwacker!bu.edu!m2c!wpi!dseah From: dseah@wpi.wpi.edu (David I Seah) Newsgroups: comp.sys.apple2 Subject: Re: Ensoniq Keywords: Apple sound Message-ID: <12752@wpi.wpi.edu> Date: 8 May 90 06:03:49 GMT References: <1981@polari.UUCP> Reply-To: dseah@wpi.wpi.edu (David I Seah) Distribution: na Organization: Worcester Polytechnic Institute, Worcester ,MA Lines: 57 In article <1981@polari.UUCP> tm@polari.UUCP (Toshi Morita) writes: >unknown@ucscb.UCSC.EDU (The Unknown User) writes: > >>In article <11669@netcom.UUCP> lyle@netcom.UUCP (Lyle Fong) writes: >>>The sound on the IIgs is among the BEST in the PC industry, capable of >>playing >>>15 sounds simultaneously with Orchestraic quality. It is better than most >>>stock Macs, and better than IBM's even with AdLib sound cards on them. >> Well, you have underestimated it! As far as I've read/been told, >>the GS's sound chip is capable of 31 channels simultaneously, yet through >>"legal" means, 15 is how many you get... As we've all seen though, trickery >>gets you much more than going through the legal means. > >I thought everyone and their dog knew this - where have you been for five >years? Give the guy a break. there are new IIGS users and new netnews dudes cropping up every day. Remember that guy who upgraded from System Disk 3.1 to 5.0? I bet he was really surprised! >The Ensoniq DOC has 32 oscillators. If monophonic sound is bearable then you >can assign all 32 oscillators to a single channel and run 32 tones. Apple >recomments that programmers write for a stereo machine and so only 16 >simultaneous tones are possible (2 DACs per tone, one for each channel). >Apple reserves the last pair of oscillators for system usage, so 15 pairs are >usable under GS/OS. There are two reasons I can think of for the 2 oscillators-per-voice rule. The Sound Tools operate two oscillators in "swap-mode", in which only one oscillator is active at a time. This allows the system to play long samples: while one oscillator is playing part of a sample, the other is getting prepped to play another chunk. The other reason is that two voices playing the same wavetable will sound "richer". There's a small difference between the outputs of any two oscillators...oscillator output is time-multiplexed. With this slight delay, you get a "chorus" effect. Two oscillators-per-channel doesn't have anything to do with stereo effects...you assign the output channel of an oscillator by setting some bits in the appropriate Oscillator Control Register. You don't have to assign all 32 oscillators to ONE channel to get 32 tones. Remember, too, that you can decode for 8 separate channels... it's all controlled by the Ensoniq oscillator control registers. >You're posting this information as though it were "t0p-sekrit insider >news" or something. I hate to tell you this, but the "Apple //gs >Hardware Reference Manual" (which contains this information) has been >available at Tower Books and B. Daltons for the past five years. Why >don't you buy one? Lyle posted a "feel good!" post, to which The Unknown User clarifies a small point. Perhaps you ought to crack open your hardware manual and check up on the DOC to make sure I'm right. Or ask your dog. -- Dave Seah | O M N I D Y N E S Y S T E M S - M | "Yargh, cats!" | User Friendly Killing Machines | .............................................................................. I-net: dseah@wpi.wpi.edu - America Online: AFC DaveS (Apple II Art & Graphics)