Rockford Fosgate 250m2, badly beaten up

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removed with this

i dont know why, at least it stays on with out them.
i believe amp melts if i keep it on more than 3seconds with Q´s on.

Been lately more Donald Duck than Gladstone Gander
 
yes, removing Q401 changes things up. speaker output is pulsating -82Volts now.
But noticed untouched channel hasn´t bias without Q425/Q424, now there is 4mV. (set it up earlier to 2mV, wont bother it at this point)


Q401 is located in that area, being right handed with heatgun i think i would not heatet that much as most heat went much opposite direction.

well, new Q401´s then? R401 and R402 are in specs.

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i made earlier this transistor comparer, there is places TO92 and SOT23.
with TO92 i reduced DC on one amp 50% changing "matched" transistors.
But with SOT23 that chinese case being so flimsy its really hard to get readings
 
Q408 and Q407 needs to be changed

Q403 and Q404 aint good pair either

MPSA56 and MPSA06, id like to get couple of those so i can choose best pair.
US newark has them but same group farnell doesn´t, my local store can get parts from farnell fast.

any recommendation replacing those?
 
got little time to mess around with this amp again, factory Q424 and Q425 is actually one of the best pair i´ve measure with my device so throw them in again, and they are rather more powerful than these new what i have 100pc.
if i put new Q424-425 i should change them to left channel too?
Is it so that high´ish DC could come from even from that Q403 which aint pair with Q404.

When i get this channel good again and start to work with left channel im gonna check those TO92 first, if theyre ok im head up Q303-304.
 
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