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Parts replacements i'm looking for the substitute for these transistors...A1011 and C2344.drivers for power amp. with 25V rail. or any complementary pair of possible drivers for this amplifier with 25VDC split PS. I'm using A1386 and C2750 power transistors. thanks.

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This is straight from the 1989 Japanese Transistor Substitution Manual.......

2SA 1011--------use 2SB 1085 A, made by Rohm

2SC2344---------use 2SD 1562A, made by Rohm

Good luck...Rob

Posted on Mar 03, 2008

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Hello
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10-1, Nakazawa-cho, Hamamatsu, 430-8650 Japan.

simply tell them you need the manual and you are doing the servicing on your own. No one in your area can help you with it.

anyway, what is wrong with your P4500, it's a good amp but sensitive. very good design, hard to troubleshoot if you're not familiar with Yamaha amps. The main parts you can not replace buying from a local store though you may get the same part numbers specially power/driver transistors. it always comes in complementary pair critically matched by tthe factory. i tell you don't get the replacement anywere but Yamaha only. Yamaha have made to order power transistors tailor made for this Amp. you'll find the same transistor number outside but when you plug the unit, it wont last and worst it bursts !!! be carefull. Very hard to scan a copy of manual for you, but if you dont get a reply from Japan you can email me and we'll try to find a way to send you a soft copy.

Reden (redrivera0314@yahoo.com)
Yamaha service from Saudi Arabia 1996-2001

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1 Answer

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