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Buya
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FM Chip
Post Posted: Wed Dec 15, 1999 10:15 am
It would seem to me that the FM chip on the Mark III is nearly exactly like the ADLIB chip on computers in all ways. It generates the sound wave on the exact same parameters. Does MEKA use the ADLIB chip to emulate the FM chip? Are you aware of this.
 
Limbs a Flyin'
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Post Posted: Wed Dec 15, 1999 10:50 am

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> It would seem to me that the FM chip on the Mark III is nearly exactly like the ADLIB chip on computers in all ways. It generates the sound wave on the exact same parameters.

most definatly. i suspect the drum kit may be different but have no hard evidence

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>Does MEKA use the ADLIB chip to emulate the FM chip? Are you aware of this.

yes to all above.
 
LSJMDM
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Post Posted: Wed Dec 15, 1999 1:01 pm
Hello :)

There are a sound emulation engine written by Richar Mitton that can emulate several YMxxxx chips at the same time with the OPL 3 chips of the Sound Blaster.
The YMxxxx (I don't remember the number :) ) of the SMS currently is not emulated, but in a few days it will :)

You can find the library in the Raze homepage. I don't remeber the URL, but you can go there by viewing the Z80 section of Zophar domain http://www.zophar.net.

Saludos,

JMD
 
Ricardo Bittencourt
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Post Posted: Thu Dec 16, 1999 12:03 am
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> It would seem to me that the FM chip on the Mark III is nearly exactly like the ADLIB chip on computers in all ways. It generates the sound wave on the exact same parameters. Does MEKA use the ADLIB chip to emulate the FM chip? Are you aware of this.

Wrong. The chip used in the soundblaster is the OPL3, and the chip used on the Mark3 is the OPLL (aka YM2413)
The sound generation is a bit different, the OPLL uses FM (frequency modulation) synthesis and
the OPL3 uses PM (phase modulation). The first one is the derivative (f=dp/dt) of the second, and that's
why the direct-mapping used by Massage and MEKA doesn't sound the same as the original (but does
sound quite close).
I uploaded the complete data book of YM2413 to the funet some months ago.
I can't remember the full address but is somewhere inside ftp://ftp.funet.fi/pub/msx
search for YM2413.LZH

Ricardo Bittencourt
 
Buya
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Post Posted: Thu Dec 16, 1999 7:47 am
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> > It would seem to me that the FM chip on the Mark III is nearly exactly like the ADLIB chip on computers in all ways. It generates the sound wave on the exact same parameters. Does MEKA use the ADLIB chip to emulate the FM chip? Are you aware of this.

> Wrong. The chip used in the soundblaster is the OPL3, and the chip used on the Mark3 is the OPLL (aka YM2413)
> The sound generation is a bit different, the OPLL uses FM (frequency modulation) synthesis and
> the OPL3 uses PM (phase modulation). The first one is the derivative (f=dp/dt) of the second, and that's
> why the direct-mapping used by Massage and MEKA doesn't sound the same as the original (but does
> sound quite close).
> I uploaded the complete data book of YM2413 to the funet some months ago.
> I can't remember the full address but is somewhere inside ftp://ftp.funet.fi/pub/msx
> search for YM2413.LZH
> Ricardo Bittencourt

I wasn't talking about the soundblaster. I was talking about the ADLIB (which soundblaster is compatible with). They both use FM sound, and they both use symilar means to produce that sound (because both produce FM sound).
 
Ricardo Bittencourt
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Post Posted: Thu Dec 16, 1999 8:01 am
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> > > It would seem to me that the FM chip on the Mark III is nearly exactly like the ADLIB chip on computers in all ways. It generates the sound wave on the exact same parameters. Does MEKA use the ADLIB chip to emulate the FM chip? Are you aware of this.

> > Wrong. The chip used in the soundblaster is the OPL3, and the chip used on the Mark3 is the OPLL (aka YM2413)

> I wasn't talking about the soundblaster. I was talking about the ADLIB (which soundblaster is compatible with). They both use FM sound, and they both use symilar means to produce that sound (because both produce FM sound).

You're right. Older soundboards uses the OPL2 chip. I don't know for sure which kind of modulation
it uses, but I assume it was FM. Anyway, emulators that use OPL2 to produce OPLL sound will only sound
right on adlib or older soundblaster models. Newer models (SB16 or better) will sound wrong.

Ricardo Bittencourt
 
Buya
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Post Posted: Thu Dec 16, 1999 12:53 pm
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> You're right. Older soundboards uses the OPL2 chip. I don't know for sure which kind of modulation
> it uses, but I assume it was FM. Anyway, emulators that use OPL2 to produce OPLL sound will only sound
> right on adlib or older soundblaster models. Newer models (SB16 or better) will sound wrong.
> Ricardo Bittencourt

No, all soundblasters have the ADLIB FM chip. That is why they are compatible with the ADLIB card (which was a sound card in inself).
I'm not talking about the music chip or the DSP chip in the soundblaster, I'm talking about the ADLIB FM chip which all soundblasters have, which is very similar to the FM chip in the SMS. Got IT???
 
Ricardo Bittencourt
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Post Posted: Fri Dec 17, 1999 1:04 am

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> No, all soundblasters have the ADLIB FM chip. That is why they are compatible with the ADLIB card (which was a sound card in inself).
> I'm not talking about the music chip or the DSP chip in the soundblaster, I'm talking about the ADLIB FM chip which all soundblasters have, which is very similar to the FM chip in the SMS. Got IT???

pft. I quit. No more wasting time in this thread.

I quote from SoundBlaster's development kit, which you should really download someday:

* Here's a brief description of FM: Each sound is created by two operator
* cells (called "slots" in the Yamaha documentation), a modulator and a
* carrier. When FM synthesis was invented, the output value of the
* modulator affected the frequency of the carrier. In the Yamaha chips, the
* modulator output actually affects the phase of the carrier instead of
* frequency, but this has a similar effect.
*
* Sound Blaster 1.0 - 2.0 cards have one OPL-2 FM synthesis chip at
* addresses 2x8 and 2x9 (base + 8 and base + 9). Sound Blaster Pro version
* 1 cards (CT-1330) achieve stereo FM with two OPL-2 chips, one for each
* speaker. The left channel FM chip is at addresses 2x0 and 2x1. The right
* is at 2x2 and 2x3. Addresses 2x8 and 2x9 address both chips
* simultaneously, thus maintaining compatibility with the monaural Sound
* Blaster cards. The OPL-2 contains 18 operator cells which make up the
* nine 2-operator channels. Since the CT-1330 SB Pro has two OPL-2 chips,
* it is therefore capable of generating 9 voices in each speaker.
*
* Sound Blaster Pro version 2 (CT-1600) and Sound Blaster 16 cards have one
* OPL-3 stereo FM chip at addresses 2x0 - 2x3. The OPL-3 is separated into
* two "banks." Ports 2x0 and 2x1 control bank 0, while 2x2 and 2x3 control
* bank 1. Each bank can generate nine 2-operator voices. However, when the
* OPL-3 is reset, it switches into OPL-2 mode. It must be put into OPL-3
* mode to use the voices in bank 1 or the stereo features. For stereo
* control, each channel may be sent to the left, the right, or both
* speakers, controlled by two bits in registers C0H - C8H.


Ricardo Bittencourt, the one who owns two YM2413, tired from discussion.
 
Michael Montague
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Re: FM Chip (Thanks!)
Post Posted: Mon Dec 20, 1999 7:27 am
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> pft. I quit. No more wasting time in this thread.

Ricardo, thanks a lot for the YM2413 documentation. That answered a million questions I had about this chipset!

(Of course it also has disuaded me from using MIDI to emulate it, hehehe.)

Thanks again!

- Mike
 
Correctius
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Post Posted: Sat Jan 15, 2000 3:33 am
Yes exactly, that says that the Soundblaster has 1 FM <------ Chip in it and the SB PRO has 2 FM <-----**** LOOK HERE **** Chips in it. You originatly said that the Adlib and Soundblaster don't use FM Sound, so you should take it back. I've programmed the Adlib card at a low level in assembler so I think I'd know more about it than you, you low life piece of crap.

(BTW when I was refering to the Adlib chip I was really talking about the FM OPL-2. Both the SoundBlaster and Adlib cards contains them.)
 
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