Pioneer SX-737 issues

[vortalexfan]

Hello everyone, the other day I was given a Pioneer SX-737 Stereo Receiver that had the infamous static rumble that was coming out of the speakers that was an indicator of failed differential transistors in the amplifier stage (which in this stereo's case was a set of 4 matched 2SA726 Transitors, of which the modern replacements were KSA992 transistors).

Well I replaced the transistors the first time around and didn't realize that the emitter and base on the KSA992 transistors were reversed from what the original 2SA726 Transistors were so I ended up installing the replacements incorrectly and when I powered it on all I got was a loud hum out of the speakers so I quickly shut the stereo down and looked up the specs of the KSA992 transistors which was when I found a thread from AudioKarma that dealt with this issue and I figured out that I had the replacement transistors in backwards (the flat side of the transistor should of been facing the front of the stereo and not the back of the stereo like the originals did).

Anyways I took out the first replacements and installed another set of replacements (making sure they were in the correct orientation this time) and after I replaced the transistors the second time around I went to test my work and this time there was no audio period (no hum, or anything) and the protection relay wasn't even kicking in either (whereas before even with the original faulty transistors in the stereo the unit worked fine just too noisy to properly enjoy).

I did read in the service manual for this stereo receiver that the amplifier board has to be rebiased everytime a transistor is replaced on the board but I'm not sure if that's my problem or not.

Any ideas as to what could be causing my issues?