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MIDIbox FM preview


TK.

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it's seems like some digital stuff??

(I can be wrong)...

but the small pcb with the xtal seems to be a Lr clock generator? the big smd chip is a dsp? (alesis? al1301) and the small is an alesis DAC? (al1201?) and the last chip is an output buffer?(lm324?)

am I dreaming? ;)

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Those old yamaha FM chips are mad!

Say what? 4Op FM (Dx100) is the second definitive element (apart from 909) on classic Detroit techno/house tracks.. Funky basses, leads, strange noises and squecks ;)

especially if you write to the registers at high speed with mutating values!

That's how its done ;)

And checked the specs:

Yamaha OPL3 (YMF262) Device

4 Operator FM Synthesis

20 Voice Channels

And it's Stereo ;)

Bye, Moebius

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Wow, you work fast!  I haven't even received my MBHP boards yet - first I have to build my SID, then I have to get going on my other chip synths.

Unfortunately, it's Saturday and I'm at work AGAIN... things aren't boding well for this at the moment, but with any luck I'll have a new job in 3 weeks which should give me a bit of free time.

You never cease to amaze, TK :)  I'm looking forward to when a PCB is ready for this (though really, it seems simple enough to wire up on some stripboard)!

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Bingo! Yes, it's the OPL3 :)

I've started with a very basic driver which allows to trigger some notes, but - please be patient - a first version won't be released until end of this year. I need this time to find an optimal user interface and an optimal sound architecture (like Duggle mentioned: even more interesting sounds can be expected once the parameters are modulated via LFOs/ENVs/Wavetables).

The prototype is not the final one. The selfmade 14.318MHz oscillator will be replaced by an integrated one, the LM314 by a TL074 for high quality sounds, I will add a second YAC512 for two additional audio channels (the YMF262 provides 4 seperate outputs), and finally I want to put this on a PCB. Hopefully the background noise disappears then (I think so...)

Here a new example (the last for this month) - drums can be accessed via MIDI now - the bass is a killer! :-)

http://www.midibox.org/midibox_fm/mbfm_demo2.mp3

Pilo: like in the first example the delay/chorus/etc effects are made with external VST effects - sorry, no DSP ;-)

Andrew: today I received a AtariST from an ebay auction (for 1 EUR) - looking forward for your YM2149F synth! :)

Best Regards, Thorsten.

P.S.: please don't start to desolder the SMD chips from old soundcards if you never did this before. I will provide a desoldering guide!

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This family of chips OPL3 etc were on all of the "Soundblaster compatable" soundcards right up until the SB AWE. This means early to right through to late 1990's. There were many millions produced. These should be easy to find at second hand computer markets and cheap.  

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i hear that the sega megadrive also has an fm chip inside (the same as in the yamaha TX81Z.. 7 or 8 dx7's in a  box)

YM2612 has more or less different specs than YMF262 - there are many generations of FM chips around.

(tx81z is multitimbral alright, but it's still 4op (vs. DX7's 6) - so less is more, or.. what?)

Bye, Moebius

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When I started wiring up my newly-arrived Core & SID modules last night, I remembered that a few years back I had pulled the old soundcard out of my 486 (when I started using it as a router).  After finding it in a drawer full of parts, guess what I found?

That's right, a YMF262!  The one old soundcard that I have, and it's got the right chip on there.  Hooray!

The card is a "Mediamagic ISP-16", for those who are looking for old ISA soundcards to loot.

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Hi there,

i found an old soundblaster in my reservoire...

yamaha YM3812 on it. Seems to be the original opl2 chip, but i cant find any specs / datasheets for this one anymore. (am i too dumb for google?)

is there any type of compatibility to the opl3 chips?

anyone?

I won't make any comments about Google here, but I believe someone posted this URL earlier:  http://members.chello.nl/h.otten/vortexion.htm

It has a link to the YM3812 datasheet, which can be accessed directly here:  http://www.funet.fi/pub/msx/mirrors/msx2.com/vortexion/ym3812.pdf

Regarding OPL2 vs. OPL3, I think that the YMF262 was the first chip supporting OPL3 (and was also backwards-compatible to OPL2).  Still, the YM3812 might make a cool project - maybe TK will get to that after his YMF262 FM synth ;-)

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hi Thorsten (and everyone else..) i found an interview with martin walker, who used to program for these chips..

http://interview.sonikmatter.com/data/martin_walker.php

he works for Sound On Sound magazine now... he posts on their forums quite often...  he is helpful generally.. if you have any problems writing the drivers he might be able to help, if he has time and feels like it of course.. if you email the magazine then i think they will put you in touch with him..

www.soundonsound.com

here are extracts from the interview..

Most of the hardware classics are already being revisited in software form, and Native Instruments' FM7 takes FM synthesis to new heights, again because it's much easier to use than the original. I missed out on FM synthesis the first time round, but met it at the deep end when programming a sound editor for Sega's Megadrive games console, which effectively contained a Yamaha TX81Z that I had to talk to at chip level. I fell in love with its unique timbres, especially the metallic and bell-like sounds, but the beauty of dealing with synthesis at a low level is that you can investigate anything that takes your fancy. I found adding a little randomness at various places to the algorithms gave FM a more living, breathing quality.

and...

-------------------------------------------------------

With the other game machines you got a few channels of square or pulse waves, plus hopefully some white noise, and from these primitive elements you had to extract the last drop of creativity. I worked at sound chip level, programming in assembly language, so that I could manipulate the chip registers every 1/50th of a second. Thus, chords could be created as very fast arpeggios to give the illusion of a bigger sound, while bass drums started with a tiny chiff of noise, followed by a decaying tone, and snare drums oscillated between noise and tone, again at 50 times per second. Sega's Megadrive was more fun, since this had the same Yamaha FM chip as the TX81Z, but I used similar techniques to manipulate the sounds, so that I could get sword clashes, gunshots, and even running water, by rapidly altering the parameters.

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