sanyo STK465Z, any good?

[senndogg]

been donated an old stereo amplifier. NIKKO, 100% genuine Japanese thing.
nothing special with it, everything seems to work, buttons, lights, switches but the sound: not!
very simple from the inside and with a general visual inspect could see 3 burned legs of the main integrated amp, a SANYO STK465Z.
the amp has failed because of on overload, this i was told.
i was 99% sure that the IC amp has gone but i still decided to repair the missing legs. after soldering some extra wires, plugged in and as expected it did not work. every other component in the pcb seems ok.
well , this is it:
http://www.ebay.com/itm/1PCS-STK465-...-/280631481393
it has 2x30W from the specs. worth it?

[Th3_uN1Qu3]

Re: sanyo STK465Z, any good?

STK chips are mostly faked these days. Will work for a test? Sure. Will hold in the long run? No. Still, if you take good care of it it oughta do. STK amplifiers haven't been designed to take a load lower than 8 ohms. Most of the time, it's using 4 ohm speakers and cranking the volume which kills them.

The fakes are easily spotted due to the low quality insides, but you can't see them without cracking them apart so it's always a gamble. Your call.

[senndogg]

Re: sanyo STK465Z, any good?

thank you unique but today i came up with the idea of switching to LM3886. it will take me some time and extra components but the conclusion will be better i think.

[Scenic]

Re: sanyo STK465Z, any good?

http://www.diyaudio.com/forums/chip-...ml#post2807672

[999999999]

Re: sanyo STK465Z, any good?

Pull the suspect chip off the board. Next, measure things. Is there an appropriate voltage level on the supply lead traces? Does the amp stay turned on? Is there a measurable audio signal present on the audio input leads? IF these things check out, then it does seem you need that chip replaced. If these things don't check out, backtrace whatever isn't right.

[senndogg]

Re: sanyo STK465Z, any good?

@scenic, well i didnt know that this swap is famous the original chip is the stk465 (not the stk459 mentioned in the forum) so the power supply is -30V:+30V and i think might be powerful enough to feed 2x LM3886 as the overall power consumption of the amplifier is rated at 250W. this will be my first LM3886 project and i'm happy about it.
@9999(9) with the chip off: power is ok, the output traces arent shorted and the input signal is there (connected my music phone in the AUX and with the 3.5mm jacket of some cheap computer speakers traced the working input). the chip seems to have been in flames if you inspect it carefully.