LC no sound

[bibilit]

I have been working in a LC board recently.

the board got new caps  (not working before)

Now the board works, but no sound is present.

I have tested a few things, including speaker of course, the board has been washed again.

Any idea how the sound is managed in the LB ?

 

[techknight]

usually a sound IC. probably a bad trace. or a corroded pad where a trace comes into the sound IC breaking its connection. I have seen it once or twice. 

 

[bibilit]

Thanks,

I have removed the Sound IC and checked traces, no corroded pad so far.

Have you ever seen the IC itself being faulty ?

 

[techknight]

rarely. actually, never. But there is a first time for everything I guess. 

 

[Bolle]

I have seen two sound ICs going bad. One was in a CC and another one on a LC.

The one in the CC did make a few pops and cracks or really quiet distorted sound sometimes but most of the time it did just stay silent.

A new sound IC solved the problem on both machines.

Unfortunately hose are Apple specific parts :/

 

[Scott Baret]

I have a very strange problem on one of my LC IIs.

The board was re-capped and most sounds play normally, but the music on Midnight Rescue does not. It comes out very, very faintly from the speaker.

One thing to note is that the music on that game is not played from .snd resources but rather from SONG resources. This is the sort of sound that newer OS releases break, although I'm running 6.0.7 on this machine (and it plays normally on all of my other LC IIs).

I've tried re-installing the program with no success. Could this also be related to the chip?

 

[Scott Baret]

ADDENDUM TO ABOVE: Remember how I said it played fine on the other LC IIs? This includes a few which have been recapped.

 

[techknight]

I have seen two sound ICs going bad. One was in a CC and another one on a LC.

The one in the CC did make a few pops and cracks or really quiet distorted sound sometimes but most of the time it did just stay silent.

A new sound IC solved the problem on both machines.

Unfortunately hose are Apple specific parts :/

Ah. Interesting. I have yet to replace a sound IC, but, I havent really seen a ton of LC boards either. just one here and there. Most of the stuff I ever saw was SE/30 and Portable. I have never seen an SE/30 or a portable with a bad sound IC except that were physically damaged/corroded. 

 

[bibilit]

Problem solved.

I lifted up the sound chip yesterday again, and reflowed it back again, and got a nice and loud chime and sound.

So probably the IC was not seated properly.

 

[PB145B]

Problem solved.

I lifted up the sound chip yesterday again, and reflowed it back again, and got a nice and loud chime and sound.

So probably the IC was not seated properly.

Awesome! I replaced a sound IC in an LC II once, but that turned out to not be the problem. It was the speaker jack, and plugging something in and out of the jack a few times solved my problem.

 

[NickNick]

Awesome you got it repaired. Often thought that was the issue on LC's with no sound. I have one as well which has been recapped and cleaned but produces no sound. How hard was it to remove the chip and place it back on? Perhaps something I should try. I love the LC pizza box machines. I actually have an LC and an LC 475 hooked up to my network in my house. These machines are used regularly by me and my friends. I got them all to stream MP3's. Its rewarding hearing an MP3 coming through an LC's speaker lol.

 

[bibilit]

 How hard was it to remove the chip and place it back on?

If you have a proper hot air station, not really hard or long, no way it can be done another way.

 

[tanaquil]

I have been following this thread with interest because I have several IIsi machines with sound issues. I haven’t gotten to the recapping stage yet. 

If you have a proper hot air station, not really hard or long, no way it can be done another way.

What do you use for a hot air station? (Sorry I keep coming into threads to ask for recs, I am building out my work bench and it seems to be the most effective way to get opinions on this stuff.)

 

[bibilit]

To be honest, the one i have is a Chinese cheap unit, scarcely used.

Capacitors are the main issue here.

 

[NickNick]

If you have a proper hot air station, not really hard or long, no way it can be done another way.

I do have one of those and various tweezers to lift chips. I should try that as I have no other idea what could be the issue. I hear sound through the headphones but very very faint if the volume is all the way up. was all you did was just lift the chip and the re-seat it back on?

 

[bibilit]

And clean pads and chip, but this is obvious.