It would be nice to know if these choices of transistor substitutes is OK - aka I don't trust my judgement

62vauxhall

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#1
This is in addition to my thread on "creating" a resistor for the Akai AA1010 I was reluctant to admit having. I got hold of the proper resistors so that's done.

I now know that the NPN of a pair of driver transitors is shot. My intention is replacing the NPN and it's companion PNP. I would do this on both channels. Sorting through what I have on hand, I've got exactly two pair of transistors that I think will work.

Original NPN - 2SD571 replace with NPN- KSA1220
Original PNP - 2SB605 replace with PNP - KSC2690

One of the two 2SD313 outputs in the channel in question is also blown and I intend on replacing all four of them with MJE15032G.

If any care to review, here are the specs for both original driver transistors and tentative substitutes

Original NPN

2SD571 NPN specs.PNG

Replacement NPN

KSC2690 NPN specs.PNG

Original PNP

2SB605 PNP specs.PNG

Replacement PNP

KSA1220 PNP specs.PNG
 

62vauxhall

Veteran and General Yakker
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Southwest Kootenays BC
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No such things as bad days, just bad moments
#3
The wider bandwidth of the new ones could be a problem, as in oscillations.
Thanks Don. That was a concern. My only concern actually.

If oscillation does occur, would it be audible or be too high and only show up on a scope? Which I don't have. If the transition frequency of the output transistors I intend to use (MJE15032G) enters the equation, that number is 30MHz.
 
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