Beautiful amp and gorgeous restoration 👏👏👏👌 Thanks a lot for showing how to adjust the DC offset, is very confused in the service manual because all are in Japanese and is not clear the step by step. All your videos were great but this one is amazing. I've some alpha's amps, know I've a better idea how to try to make this delicate process. Thanks 🙏
Glad it can help others, yes the service manual makes the whole process so confusing to understand! It's not that bad once you get a handle on it, I was surprised myself!
Great vid! I've always luved Sansui. Always beautiful through and through! Wonderful to look at, and if not more wonderful to listen to! But, this Alpha AU-907MR is more complicated than a Helicopter!! I thought i wanted this gold gem? Not so much now. Theres No one in NYC who can work on it?? I know ever tech cannot work on Sansui successfully period. I own three. G-7500, i brought new in the late 70s, & a G-9000 & an AU-D11ii much later. My two Receivers need restoration. So could my AU-D11ii. Its my daily. I dont even turn it off! I've heard horror stories about their AU-X1 being unstable. So, i avoid those rare gems as well. I hear good things about the 919! Although, the 719 is much more popular. If you were at lesst in the US i wouldnt hesitstate to have you restore all three! 👍
I was measuring the heatsinks inbetween the hot side and cold sides to get an average temperature. It’s not perfect but a rough idea of temperatures :)
@@whatcouldgowrong7914 Great. Thanks. Good enough! Seems reasonable. I own the 907NRA - another late Sansui masterpiece. The value proposition for high-end fidelity for these later Sansui's is just unbeatable. And they are such masterpieces of build quality. Cannot find any of that today. For the same price. Cheers!
Thank you, a great video. thanks to your video I am doing it on my sansui 907MR. but I don't really understand what you did from your 15th minute, I watched it dozens of times and don't understand. Please help me in more detail what you did. For example, when adjusting VR5 R/L; then " power apm direct operation " ; Where is " input selector " set up? ; Is the volume set to the largest or smallest position? ; And where do you plug that short RCA cable? I read the instructions and I didn't understand anything like you did. Please help me, sorry because I'm not too good in this field.
Awt the volume to highest and move to middle also just to see how much the DC offset moves around. I used CD input with shorted rca connectors. Set to CD input and “integrated” - You should see the DC value change as you increase volume if its on the right switch settings :)
so, around 68mA per device with RE 0.22Ohm and rail voltage 38V?. since this amp is essentially a bridged mode i'd say yes, they're quite low bias. i'd say try 17mV if you're comfortable with the heat. total idle heat dissipation per channel will be around 22W
It was calibrated at about 15c so odds are it would be around that indoors which is why I took the low end 🙂 Really comes down to how much you want to preserve the amplifier I guess or get the most out of it 👌 Not surenwhy 8.8mV was chosen for the factory
