[eptheca]

Ok, yeah, I see it now
thanks

I have a 40 pin YM2149F and a 28 pin AY-3-8912A
do they sound the same?
any preference?

[lemonhorse]

> do they sound the same?
I think so, yes. But I can't tell. I had fun with both chips, but not at the same time.
I just got one MB AY(YM) and did no comparative soundtest yet. No preference on my side.

This post has been edited by lemonhorse: 03 November 2011 - 15:43

[lemonhorse]

Please update to MBAY V2.1
* MIDI Program Change implemented (0 = Load Internal Patch, 1-127 = load Bankstick Patch)
* Found a Bug in Fx Function (Note#1-3 ABC)
* Some MIDI CC LCD Screen refresh improvements
* GATE (0V / +5V) - Core8 J14 @TONE A MIDI CH » Note ON (+5V) Note OFF (0V)

=> http://www.midibox.o..._ym_v2#software

This post has been edited by lemonhorse: 28 November 2011 - 20:30

[mrspring]

I found 33 x AY38912/P in my stash, all unused, all from the same batch.. I guess they should all work..

Boards on order, can't wait to get stuck in to this!!

[lemonhorse]

hi mrspring,
wow 33 AY chips!

are the chips from microchip?
i ask because some of them (AY38912A/P, AY38910A/P) have no noise - just tone abc.

no problems with:
GI AY38912 CDA, Yamaha YM2149F (let me know if you have successfully tested other chip devices!)...

This post has been edited by lemonhorse: 21 December 2011 - 19:49

[mrspring]

Yup.. All microchip i'm afraid ;(

on closer examination there are 3 distinct groups here, with different styles of printing on the surface.

about half of them are White microchip logo AY38912/P9032CEA with centered print, and nearly half are with thinner print offset downward, and there is a used pair of AY38912/P9043CEA with a black (reversed) microchip logo.

They all came from an amstrad/oric/msx service rack..

So they could all be useless? LOL.. easy come, easy go!!!

I got my parts for the midibox AY2 today, but i don't think i will get to build it till January to test them.. unless there is a fast way to test You know of?

[lemonhorse]

Hi mrspring!

Quote

So they could all be useless?

No, in worst case there is no "noise" (pseudo random square wave output) but Tone ABC.

Quote

They all came from an amstrad/oric/msx service rack..

This is a good sign...

Quote

...unless there is a fast way to test You know of?

There is no such method of quick and easy noise testing as far as I know.
I was confused by this noise problem by my self. There was no difference or notice about the "no noise" issue in the AY38910A Datasheet from Microchip.
If You want want me to, I can do some testing. (I just did a AY/YM chip interchange with IGI - because he had the AY "no noise" type from Microchip.)
In the end is good for all MBAY builder to know which chips are acceptable. So I'm very interested in the results.

This post has been edited by lemonhorse: 22 December 2011 - 14:22

[mrspring]

OK, well they are all quite old, they were sorted by intended model, these were for oric and amstrad.

I remember th oric DID have a noise generator, it had sound effects commands in it's basic, and one of them was EXPLODE (or something) which made
a whitenoise burst with some sub square mixed in for a nice rumble.. IDK, i may be wrong.

and the 2 'used' chips are actually newer then the unused ones, and definately different - they have no 'taiwan' mark on them, while the 30+ all do..

I also found 3 x YM2149F in the Atari ST section.. So they should be OK even if the others are duds..

OK for a test, PM me Your mailing address and i will send You 2 of the 8912 - 1 of each style/batch - for a test..

[lemonhorse]

Quote

I also found 3 x YM2149F in the Atari ST section.. So they should be OK even if the others are duds..

Year right.

Quote

OK for a test, PM me Your mailing address and i will send You 2 of the 8912 - 1 of each style/batch - for a test..

Great. I will do.

This post has been edited by lemonhorse: 22 December 2011 - 15:20

[lemonhorse]

Updated: List of checked Soundchips:
http://www.midibox.o...sted_soundchips

Thanks to mrspring ;-)

This post has been edited by lemonhorse: 31 December 2011 - 13:49

[mrspring]

This is where we are at..

Shot of it's guts, with DIN and AY board mounted on the walls, Core 3 with external pots for the LCD, classic ebay cheapo LCD etc..



here's the CS as of now.. yes, it's not very neatly drilled, but that's because i am not a neat person... the 12 buttons on the left have LEDs built in,
which seemed like a good idea, but the quality is poor, despite them costing nearly 3euro each - they sometimes trigger without touching them :(



I now have a working system.. was stumped with no audio out, until i grounded the AY board, now it's full of win..

this is 2 'stock' voices testing - check out about 5 mins in for lol chipsound glitchtime..



to do: bankstick, led matrix, second audio board & switching for stereo out..

Thanks to Lemonhorse for the PM guidance and the project, oh and Mike for the boards ;)