Philips Music Module - MSX Audio Bios upgrade schematic

Page 1/3
| 2 | 3

By Colemu

Champion (474)

Colemu's picture

10-01-2017, 14:59

I used to have an upgraded Philips MM but sold it a few years ago when money was tight.
I've now bought another Module from Retrofan but it does not have the MSX Audio Bios/Basic, only upgraded sample ram.

I don't think the upgrade boards are available any more, so wondered if the following documents are valid for the latest V1.3 MSX Audio Bios upgrade. I think they were written around the release of V1.2, so thought I'd check before attempting this upgrade.
http://www.msxpro.com/hardware/mm_upgrade/msxaudio-BIOS-EN.txt
http://www.msxpro.com/hardware/mm_upgrade/msxaudio-bios.gif

Thanks in advance! :)

Login or register to post comments

By marcoo

Expert (81)

marcoo's picture

10-01-2017, 16:14

Bas kornalijnslijper has Some new pcb's I ordered one for my second mm ,and got it last week From him,
If you send him an e-mail that you want to order a music module extender he Will send you the details

By Colemu

Champion (474)

Colemu's picture

10-01-2017, 16:18

marcoo wrote:

Bas kornalijnslijper has Some new pcb's I ordered one for my second mm ,and got it last week From him,
If you send him an e-mail that you want to order a music module extender he Will send you the details

Great news! I'll drop him an e-mail! Big smile

By Colemu

Champion (474)

Colemu's picture

21-01-2017, 19:52

Extender arrived today, converted to MSX Audio bios V1.3 and installed today.

Works great, but sound quality isn't the best. Probably wants recapping, these things are getting old (aren't we all!)

If anyone else need one, contact Bas Wink

By marcoo

Expert (81)

marcoo's picture

21-01-2017, 20:25

How did you connect your mm with the cinch connectors or via the MSX
The sound directly from the MSX is verry soft but with the cinch it's good
You van modify that too
Replace R41 with a 27K resistor and it should work better

By Colemu

Champion (474)

Colemu's picture

21-01-2017, 21:05

I tried both, it is barely audible listening through the MSX Turbo R ST (scart). Even quieter than the MSX Music (which I also find too soft and quiet in this machine).
A lot better (clearer & louder) through the cinch (phono) connectors, but a little sound distortion on some music (Compile games like Golvellius 2 - particularly in the title music)

Does the resistor 'fix' resolve the volume levels through the MSX, or does it increase the volume on both outputs (MSX & cinch)?
I'm worried it might increase the distortion...

By Colemu

Champion (474)

Colemu's picture

22-01-2017, 07:20

after reading another thread, I gather changing R39 to either 4.7k or 2.2k (not sure which as not clarified in that thread which one solved the issue) should solve the distortion issue.

I'll try changing both R41 to 27k and R39 to 4.7k (or 2.2k if still distorted)

By Meits

Prophet (4080)

Meits's picture

22-01-2017, 13:32

The output of the ST is in fact quite bad. I refuse to use the audio from its own output. I guess this picture shows why:

It pays out to have an MSX-Music in a slot expander and use its output instead.

By gdx

Paragon (1364)

gdx's picture

22-01-2017, 14:38

Meits,

This demonstrates nothing. The FM-PAC has 3 levels of sound output. Adjustable with a switch (low, medium or strong). You tested on which position?
I did not notice that the FM of my FS-A1ST was especially bad. To judge whether the FM output is good or not: we must compare with the level of the internal PSG on each MSX.
One sound output must not stifle the other(s). The balance of between each level is the most important.

By Meits

Prophet (4080)

Meits's picture

22-01-2017, 14:42

It demonstrates quite something. Both are as loud as they possibly can output while the input on the sampler is exactly the same. Therefore the noise is of equal proportion. If you amplify the output of the ST you'll be hearing quite a lot of noise, while the FM-PAC's audio stays rather clear of it.
This FM-PAC has its own rca output and is recorded using that in stead of the output of the ST.

The mix balance of the ST's own MSX-Music and the PSG is good. Taking that in account this demonstrates that the ST's audio is crap as hell.

By gdx

Paragon (1364)

gdx's picture

22-01-2017, 15:04

The FM-PAC is this:
http://www.msx.org/wiki/Panasoft_FM-PAC

There is no other. There is no RCA.

I did not notice any particular noise on my FS-A1ST when I use the FM.

Page 1/3
| 2 | 3
My MSX profile