Commodore 64 sound is quiet

[Videogamecollector123]

I just got done trying(and failing) to realign a 1541 drive. I had to take the drive and computer to my school to use the oscilliscope and tried for a couple of days to get it to work. Anyway, when I got the computer home(after buying another drive) I discovered that the sound had gotten quiet. It still works but I have to crank the volume up and there is a hum on top of game sounds plus occasional pops(On Ms. Pac-man they seem to happen whenever the screen changes). I've read that this is either the sound chip or the capacitors around it. How should I go about fixing this? Is there anything I can besides shelling out for a new SID chip? I run the sound through RF and use an RF to coax adapter to plug it into the tv. There is a 6581 0384 SID chip inside.

[Videogamecollector123]

Could the power supply be to blame for this? I've heard they're not the most reliable and this page says that it can affect the audio. I've got the original black ribbed power supply.

Edited April 13, 2013 by Videogamecollector123

[Osgeld]

just chcek the caps before shotgunning it, look for puffyness, leaking, burning etc, to be totally sure you would need to remove them and test them, but at that point replacing nearly 30 year old caps seems wise

 

also check for any broken/cracked/loose solder connections and reseat any socketed chips

[Dripfree]

My bet is that its the caps like Osgeld said look for puffyness and leaking. I have never seen this on a c64 but I have had the same problem on a game gear and a sega genesis. Sega was known for using bad caps. In both circumstances changing out a few caps solved the problem. It was cheap and easy if you got basic soldering skills. Good luck.

[ApolloBoy]

I'd check out that PSU, those ribbed ones are notorious for dying and taking the C64 (or parts of it) with it.

[Videogamecollector123]

I'd check out that PSU, those ribbed ones are notorious for dying and taking the C64 (or parts of it) with it.

So what's a good replacement? I might as well replace it regardless if it's the cause of the audio problem.

[Hatta]

The usual replacement is a C128 PSU with a C64 compatible end spliced on. The C64 PSU delivers 9VAC, which is pretty unusual. You can in theory use a NES wall wart to supply the 9V AC, but you'd need a source of 5V too. So you're looking at 2 PSUs to power one machine unless you get clever.

 

I'm really surprised no one has built a small breakout box with a female ATX power plug and an inverter circuit to get 9V AC. It's such a common problem and I know people love off the shelf solutions like tht.

[Arkhan]

So what's a good replacement? I might as well replace it regardless if it's the cause of the audio problem.

 

Find a sweet Recoton powersupply for it.