No ADPCM sound.

[awack]

I have not been able to find a post or topic about this problem, a problem that im having with my pcengine duo, i have no ADPCM sound fx, the cd music and psg sound are loud and clear and the head phone jack does not work either so i dont think its the laser.

[Joe Redifer]

That is a very odd problem to have!  The laser definitely couldn't be the issue if it is loading the game and playing the redbook audio.  My guess is that either the ADPCM chip itself is shot, or ummm, yeah.  That's all I've got.  Could be a capacitor issue, you never know.  Does anyone know if the ADPCM has its own capacitor?

[D-Lite]

So you're not hearing any voice sound effects, yes?

If so, I know the source and have fixed one before.  The M5205 Oki chip that's at the top of the Duo PCB is the one that's the problem.  I've swapped it out and had it work perfectly after that.  I have a small supply of those (hard to source).

[CrackTiger]

I once had a PCE CD-ROM that played staticy ADPCM sound effects.

When I sold it I described it honestly(of course ).

[awack]

That is a very odd problem to have!  The laser definitely couldn't be the issue if it is loading the game and playing the redbook audio.  My guess is that either the ADPCM chip itself is shot, or ummm, yeah.  That's all I've got.  Could be a capacitor issue, you never know.  Does anyone know if the ADPCM has its own capacitor?

Yea it is odd as it seems that the majority of problems seem to come from not having or low redbook audio....but yea i think your right about it being the chip or a capacitor.

So you're not hearing any voice sound effects, yes?

If so, I know the source and have fixed one before.  The M5205 Oki chip that's at the top of the Duo PCB is the one that's the problem.  I've swapped it out and had it work perfectly after that.  I have a small supply of those (hard to source).

Yes, no voice sound effects, for example the voice in gate of thunder when you pick up a weapon or power up is gone along with other sound effects such as when your ship or a boss explodes. I emailed the seller but if that does not work out and if your selling the M5205 Oki chip how much do they go for?

[D-Lite]

Yes, no voice sound effects, for example the voice in gate of thunder when you pick up a weapon or power up is gone along with other sound effects such as when your ship or a boss explodes. I emailed the seller but if that does not work out and if your selling the M5205 Oki chip how much do they go for?

It's been so long since I sourced them I can't remember, but it wasn't cheap.  Somewhere around $20 if I recall for the chip.  I got 25 of them since the vendor was reluctant to not sell in a bigger bulk (as most vendors seem to be, at least those carrying more outdated ICs like this).

[PCEngineHell]

http://www.hkinventory.com/public/OfferInventResult.asp?Order=1&pnums=M5205+Oki&crit1=&crit2=&category=&product=&keywords=&words=3&country=&postdate=&brand=&crit3=&crit4=0&datecode=

http://www.netcomponents.com/results.htm?t=f&r=1&d=1&pn1=M5205+Oki

http://oki.isocomponents.com/part/OKI99
scrolldown page


Yea,they are not the easiest to locate. Some arcade pcbs use them too. There are other shops that carry it,but you really have to dig around. There is also a MOT chip with the same number,not sure if it is  a drop in replacement or what,so prob best to avoid it.

[D-Lite]

http://www.hkinventory.com/public/OfferInventResult.asp?Order=1&pnums=M5205+Oki&crit1=&crit2=&category=&product=&keywords=&words=3&country=&postdate=&brand=&crit3=&crit4=0&datecode=

http://www.netcomponents.com/results.htm?t=f&r=1&d=1&pn1=M5205+Oki

http://oki.isocomponents.com/part/OKI99
scrolldown page


Yea,they are not the easiest to locate. Some arcade pcbs use them too. There are other shops that carry it,but you really have to dig around. There is also a MOT chip with the same number,not sure if it is  a drop in replacement or what,so prob best to avoid it.

Cool, thanks for the sites.  I absolutely hate how no IC/Component website lists prices.  Need a damned quote for everything.  That's why I had to buy 25 of them from whatever the Florida place I got them from was.  Was the only way to not get raped on them.

[PCEngineHell]

Yea,like I said too,I know nothing about the MOT chip,shares the same number but that can mean nothing at all. The Mot is on the third link. Yea I agree,its a hassle to have to sign up to see prices,ect. The prices should be up front so you can just make the decision if you want them or not in advance,not after the fact you had to do the run around of making a account. I really wish Parts express carried stuff like this. They carry vac tubes,ect,so I am surprised they dont...

[Duo_R]

note - replacing the chip d-lite listed did not fix my adpcm issues. still working on this.

So you're not hearing any voice sound effects, yes?

If so, I know the source and have fixed one before.  The M5205 Oki chip that's at the top of the Duo PCB is the one that's the problem.  I've swapped it out and had it work perfectly after that.  I have a small supply of those (hard to source).

[Fakk2]

I have ADPCM issues also along with regular sound fx issues..