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FRANCE

This was the very beginning of my noisy tests and researches on the YM2612 chip CSM mode (speech synthesis) found on the SEGA Megadrive / Genesis consoles.
These tests have served the development of the FMDRIVE Vsti and the special implementation of the CSM I have used.
http://www.alyjameslab.com
Also possible future implementation on the hardware side...(Seb plz add this to GENMDM smile )
This is a custom ROM (running on an Everdrive card) that I made with very basic control on the joypad that sends register writes to the YM2612 chip in real-time.
Of course... to actually make a useful use of the CSM mode, live inputs by hand from a joypad is not fast enough.. hahahaha
congrats if you are able to watch this until the end...
joking aside, there is some really nice stuff we can do soundwise with the CSM...and nobody have used AFAIK this features on the Genny..

Last edited by Aly James (Jun 1, 2013 12:38 am)

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Aly James wrote:

This was the very beginning of my noisy tests and researches on the YM2612 chip CSM mode (speech synthesis) found on the SEGA Megadrive / Genesis consoles.
These tests have served the development of the FMDRIVE Vsti and the special implementation of the CSM I have used.
http://www.alyjameslab.com
Also possible future implementation on the hardware side...(Seb plz add this to GENMDM smile )
This is a custom ROM (running on an Everdrive card) that I made with very basic control on the joypad that sends register writes to the YM2612 chip in real-time.
Of course... to actually make a useful use of the CSM mode, live inputs by hand from a joypad is not fast enough.. hahahaha
congrats if you are able to watch this until the end...
joking aside, there is some really nice stuff we can do soundwise with the CSM...and nobody have used AFAIK this features on the Genny..

I've seen it used in old off-shoot Sonic the Hedgehog hacks on Sonic Retro back in like 07-08. Cool, kinda funny smile will be neat to see be used again.

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ad-hell-aide

I will add this to GenMDM.

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ad-hell-aide

Awesome work!

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Melbtown, Lolstralia
little-scale wrote:

I will add this to GenMDM.

FUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUU

this looks like it has ridic potential

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detroit

i like these sounds a lot

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New York City

Can you release this ROM? It's very useful.

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Milwaukee, WI

Paging Delek!

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New York City
Theta_Frost wrote:

Paging Delek!

He was paged already a while ago:
http://www.delek.com.ar/forum/deflemask … -csm-mode/

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FRANCE

Straightforward implementation of the CSM mode will be cool but I will add some details and notes regarding the way I have used it in FMDRIVE to Seb and anybody who will need to implement it smile
Being not familiar with music trackers I am more inclined to use DAWs.
Actually (until I got my GENMDM)  I use Valleybell mid2vgm that is working fine to convert MIDI data to VGM except it did not convert yet CCs to YM2612 registers and pitch informations sometimes ends wrong.
Freedom of composing music in DAW with FMDRIVE instances and then play it on the console after conversion is pretty cool until I can live control the GENMDM with FMDRIVE smile .

Oh and I will release that particular ROM if there is some interest, it works on the hardware and should also works in emulators that support CSM mode correctly... IIRC REGEN do.

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United Kingdom

Would be interesting to have a mess around with the ROM.

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FRANCE

That should be enough for a start to anybody starting to implement CSM smile enjoy!

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New York City
Aly James wrote:

Oh and I will release that particular ROM if there is some interest, it works on the hardware

Yes please, sounds like a great source for crazy samples for me. I'd be happy to run it on my machine.

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FRANCE
akira^8GB wrote:
Aly James wrote:

Oh and I will release that particular ROM if there is some interest, it works on the hardware

Yes please, sounds like a great source for crazy samples for me. I'd be happy to run it on my machine.

Ok guys smile
let me write a basic instruction for the joypad control...later I will also release a more featured one that uses both joypads and combination of buttons...

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Tokyo, Japan

Ok, Im really sorry but can someone explain what the fuck is going on here? Does the YM2612 have a speech mode in it that nobody used? Is it a kind of primative formant synthesis or something?

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FRANCE
Lazerbeat wrote:

Ok, Im really sorry but can someone explain what the fuck is going on here? Does the YM2612 have a speech mode in it that nobody used? Is it a kind of primative formant synthesis or something?

Absolutely right smile
It is not really easy to program to actually produce understandable speech  but the technology is definitely here in the YM2612...
I have made a few video on the FMDRIVE VSti to showcase what you can do with it.
I have found some rare use of CSM inside some Game Arts games for MSX:
The Silpheed game on PC88 MSX computer featuring a very similar chip than YM2612 wih the exact same CSM feature.
In use here to produce the robotic speech:

and Here:

The FM sound of YAMAHA has the ability to key-on / key off immediately (some channels) or all channels when the timer A built-in overflows.
It is called "CSM speech synthesis mode" and stands for Composite Sinusoidal Modeling.
A type of speech coding, CSM speech synthesis is a technique to reproduce with the combination of multiple sine wave, the original data of a vocal sample. 

There is a theory using FFT to "de compose" the frequency content of a signal into a sum a different sine waves, in the time domain with different pitches and volume.
Based on this theory, If you play at the same time more than one sine at an appropriate TL volume and frequencies , you can reproduce the waveform similar to the original waveform.
YM2612 can output 4 sine with 4 different Frequency and 4 Different TL volume.
FMDRIVE Vst uses that with MIDI CH1 , 11, 12, 13 to control Frequency and Volume an additional CH 14 to control the timer A.
You can also midi learn these controls to any midi controller and you're good for some live talking shit smile

This mode is also useful to output new type of sounds similar to having a powerful filter on board...and that is what is very interesting in addition to the speech thing.
My testing have shown some really cool stuff smile

Last edited by Aly James (May 9, 2013 4:20 pm)