M-audio EX66 strange Capacitor name or type?

[Shandryderrick]

Hi, i have this old m-audio ex66 that has a distortion problem.
i think i figure out the problem but i don't the name of the type smd capacitor or witch value it should be.
its the gray one that my tweezers are on. you can see 4 more more on the board.
it's very soft, melts and breaks down very easy with the solder iron, its not like other smd capacitor that are hard.
try a regular smd capacitor and its giving me strange noise, so i think it need's that type capacitor.
i have some other parts of m audio but i can't seem to find it in any of the ones i have
try looking for schematic couldn't fine one, so if any body has it please let me know
thank you

[nickb]

It's probably polystyrene, they are chosen for their excellent characteristics. And yes, they will melt if you put a soldering iron on them so never do that. It almost certainly wasn't your problem and without knowing the value I'm afraid you're not in a good place. You can try contacting them and asking for more info.

[Shandryderrick]

hey thank you,
yeah reading more about polystyrene, i think you are right.
I got some info from M-audio, but still waiting on the value from them.
I was able to remove one of the polystyrene cap it without destroy it, with the hot air station.
So i have one working again.
But thanks for the help, i am one step forward

[nickb]

I'm glad you heard something from them. My secret weapon for soldering these caps is to use lead free low temperate solder Sn 42% / Bi 57% / Ag 1% type 4902P by MG Chemicals. It melts at 138C.

[Helmholtz]

From what I've read about polystyrene caps I always thought they were not suitable for SMT, e.g. https://www.electrocube.com/pages/wh...ors-data-sheet or
https://www.electronics-notes.com/ar...olystyrene.php or http://my.execpc.com/~endlr/film.html
There is good reason that the leads of PS caps are typically very thin.

Are there current manufactures of SMD polystyrene caps?

[Shandryderrick]

Yeah Helmholtz i see what you mean.
i don't know if there are any current manufactures of SMD polystyrene caps.
looking o the internet i can't seem to find any. If not i will try putting a regular one on it see if it work.
But i am still waiting on the value from M-audio.
I talk to the owner and he understand, wants see if it can fix before buying a new one.
but thanks for the help

[nickb]

It's kinda funny, I guess being brought up with polystyrene caps, whenever I'd seen these I had just assumed they too were polystyrene simply because they melt so easily. I see that a substitute is available, thanks HH. I have used acrylic SMD caps in some cases.

[Helmholtz]

It's kinda funny, I guess being brought up with polystyrene caps, whenever I'd seen these I had just assumed they too were polystyrene simply because the melt so easily. I see that a substitute is available, thank HH. I have used acrylic SMD caps in some cases.

My colleagues who designed automotive electronics favored polyphenylene sulfide (PPS) SMD caps for demanding applications.
https://www.wima.de/en/our-product-r...of-dielectric/