Wondering if someone knows about amplifiers

I have a Sa-100T from sound appeal. Something shorted and now it doesn't produce any sound. After a tear down my noes led me to one of these

being really hot. and smelling of burnt hardware. I don't know what this is, and so can't order something new to try and fix it. If anyone knows and could let me know, that would be fantastic. It's already broke, so Can't really brake it any more.

Not an expert on amplifiers but that looks like it could be a capacitor or maybe a transistor. Are there three "legs" on that component or two? Are there any marking on them?

Two legs, no markings.

Going by the symbol on the circuit board, it is an inductor.

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judging purely by the silk screen marking. It looks like it might be an inductor. I know audio equipment uses ferrite coated inductors to reduce noise. So it could very easily be one. But don't quote me on it

ha ha, beat me to it by about a second

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Any way to know what size? Or is there a standard?

1) Find a service manual with the circuit diagramm and look up L4 in the component overview
2) write a Mail to "[email protected]", describe your case and ask if they could tell you what kind of inductor it is.
3) (NOT recommended) Desolder one of the other (working ones), grab your wave gen and oscilloscope and follow this guide: http://www.wikihow.com/Measure-Inductance
4) Look if there is anything stamped in the bottom of the inductor

Wish I had an osmelloscope. The 2 may be my only option.

Do you watch AvE?

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I do that guy is awesome.

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Chokes do get hot though, that is normal operation. They usually sit at around 70 °C or so.
Why assume if you can measure. Grab a meter and check that thing, then you know if it's broken or not.
If you substitute a choke with an off-spec one, that's where you'll probably see magic smoke unleashed, so test before swapping those things out!
Normally, is an amp dies completely without any sign of life, and there is no sign of a cap that has blown its top or a blown fuse, I would sincerely measure out the power stage MOS-FET's or the power stage main power transformer, because that would be my number 1 suspect. Also measure the input stage. Do not guess, it amounts to nothing!