Yep, the ISD chips seem to be quite popular for this kind of thing...they are all over the web and folks here (in the ITP program) seem to like'em too. Still they seem a bit...inelegant to me. Not so good frequency response. Having to program them via analog means one by one (although I guess there are some industrial ($$) programmers out there). I'd still like to have the sounds as data in memory and then play them out a DAC or something. When I worked briefly at Williams Electronics sampled sounds would get clocked out as a bitstream using some form of delta modulation which a codec chip would then reconstruct into the waveform. Cheaper than DAC's I guess, at least at the time (mid 80's). Here is an AES paper about sound electronics for toys which is related to all this...a nice overview but not so many details... http://www.techno-mind.com/snd4toys.htm Thanks for the info so far. I hope others will feel free to chime in with alternatives to the ISD path. cheers, Phil At 4:14 PM -0700 10/14/01, Allen Mahurin wrote: >The ISD chips are great for recording/playback voices. >However, anything above 4kHz (which you'll exceed if >doing any siginifcant sound effects or music) will be >lost or degraded. For quality sound and a decent >frequency range, I'd suggest finding another chip. > >Good luck, > >ATM > >--- Nicolas Fournel >wrote: >> Hi Philip, >> >> I'm in the exact same case... I would like to play >> some sounds (even just one...) of my owns with a >> Pic. Software and sound design is not a problem, >> but the hardware part is tougher... And I really >> would like it to be small, too... >> >> For (C) you can check: >> >> http://www.quadravox.com/ >> >> They are doing a programmer to use your .WAV files >> with ISD chips. There have beeen a few articles on >> the ISD chips in Nuts & Volts >> Let us know what you find, >> >> Nicolas >> >> >> >> >>> Philip Galanter 10/14/01 >> 02:59PM >>> >> Hi all. I am an artist with some strong software >> chops (including >> some firmware work in a previous life), but weak >> electronics skills, >> and working on a project that will result in 100 >> small identical >> circuit boards. (enough so that everything I have >> to do by hand >> needs to justify itself, but so few that jobbing >> things out to >> fabricators or custom chip labs may not be cost >> effective. (did I >> mention this is on a limited budget? Think starving >> artist here...)) >> >> I am getting up to speed on the world of PIC, and >> want each of the >> above boards to have "fancy sound"...i.e. a small >> speaker and the >> ability to make high quality sounds of my own >> design. (I am an >> expert synth player/programmer). Each board only >> needs to make about >> 10 short sounds, and using sampled sound I could get >> by on 10 to 20 >> seconds of total sound. But I have to be able to >> sculpt the sounds >> myself... >> >> It seems to me the alternatives are as follows: >> >> A) Use the PIC to synthesize square wave based >> sounds directly. (+) >> Cheap (-) Limited timbres, may use lots of PIC >> cycles >> >> B) Use the PIC to play back sampled sounds via PCM >> out a single pin >> (+) Cheap (-) Have to find a way to convert sampled >> sound files to >> PCM files, have to have lots of non-volatile sound >> memory ($$$), a >> way to program sound memory, may use lots of PIC >> cycles (?) >> >> C) Use an external sound chip triggered by the PIC >> (+) Versatile, low >> load on PIC cycles (-) Have to find a way to load my >> sounds into 100 >> sound chips, more chips means more $$$ >> >> D) Use a second PIC with 8 (12? 16?) pins dedicated >> to driving a DAC, >> and have the first PIC tell it which sound to make >> when. (Bad S/N >> not so much a problem as long as I get to design the >> sounds). (+) >> Versatile, low load on PIC cycles (-) have to have >> lots of >> non-volatile sound memory ($$$), a way to program >> sound memory, and 2 >> PICs ($$$) > > >> So here are my questions: >> >> Does anyone have good examples (circuits, code) for >> any of these (A-D)? >> I'll be happy to buy a book if that is where the >> info is... >> >> For (B) would my best bet be using a second flash >> memory chip for the >> sounds, and then have the PIC read the memory and >> send it out the pin >> I use for PCM output? How would I get the sound >> data into the (100) >> memory chip(s)? (I'd like to avoid buying an >> expensive PROM burner >> or the like just for this). >> >> For (C) any specific sound chip suggestions? (URLs >> especially welcome!). >> The ones I've seen are mostly record/playback >> devices...like for an >> answering machine or a toy. It would be very >> tedious to program 100 >> of these each with 10 different "messages" via >> analog recording or >> the like. And I just need playback. >> >> For (D) anyone done this? DAC chip suggestions? >> Circuits? >> >> And finally... >> >> What speaker should I use? And will I need a >> transistor acting as >> power amp or something? It needs to be small (one >> inch diameter or >> less...flat-ish). Best if it can just be mounted >> right on the board. >> Most Piezo sound devices seem to be more like preset >> buzzers, but I >> like the idea of using a Piezo element. I can find >> lots in the >> catalogs...but I can't tell from that which will >> sound the best. >> Obviously I am not going to get bass response! Also >> again, any >> circuits I can crib? >> >> I know this is a lot of questions...any partial >> responses would be >> very welcome...and thanks so much for your time! >> Phil >> >> -- >> >> Philip Galanter New York University >> Associate Director 251 Mercer >> Arts Technology Group New York, NY 10012 >> >> -- >> http://www.piclist.com hint: PICList Posts must >> start with ONE topic: >> [PIC]:,[SX]:,[AVR]: ->uP ONLY! [EE]:,[OT]: ->Other >> [BUY]:,[AD]: ->Ads >> >> -- >> http://www.piclist.com hint: PICList Posts must >> start with ONE topic: >> [PIC]:,[SX]:,[AVR]: ->uP ONLY! [EE]:,[OT]: ->Other >> [BUY]:,[AD]: ->Ads >> >> > > >__________________________________________________ >Do You Yahoo!? >Make a great connection at Yahoo! Personals. >http://personals.yahoo.com > >-- >http://www.piclist.com hint: PICList Posts must start with ONE topic: >[PIC]:,[SX]:,[AVR]: ->uP ONLY! 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