SONY TAN80-ES questions

[edrel sison]

Hi to all,

I own a SONY N80-ES power amp with its right channel blown. This amp normally dissipates heat a lot and my previous mistake was using it without installing a fan over the heatsink. Now that I am looking for replacements of the blown NEC drivers & SANKEN output transistors, my questions are:

1. Will a TOSHIBA output transistor sound as great as the SANKEN? TOSHIBA 2SC5200 can replace the SANKEN C3856 & TOSHIBA 2SA1943 can replace the SANKEN A1492. its very difficult to get the original SANKENs in my place.

2. Shall it be better if CC resistors on the bias circuits be replaced by METAL FILM types?

3. Has any kind soul out there possess a service manual for this amp and share his experience servicing.


This is a wonderful amp and I would plan to keep and use it for quite a long time. Thanks in advance for your inputs and guidance.

regards,

edrel

[machinow]

Hi,
you can use Toshibas instead of Sankens, I suppose they're slightly more powerfull, but generally when replacing outputs , drivers and pre-drivers in a power amp BE SURE to set the Iq set trimmer to min. position /sometimes leftmost, sometimes rightmost position, but generally when its resistance is maximal/. Because replacing the BJTs with more powerfull types will increase the Iq /quescient current/. Recommendation: always check out the Vq circuit in a blown amp, is it working correctly.
After you replace the BJTs, you can adjust Vq trimmer so that the voltage across the emitters of the outputs /or across the power 0R1-0R33/ resistors is around 10-40 mV in the different topologies, typically 20mV

[edrel sison]

Thanks Machinow, will heed your advise and check. I would hope that the Toshibas will sound as great aside from being slightly powerful. By the way, my SONY N80-ES amp will drive a decware imperial by jensen. they are great combos!

regards,

edrel