You’re doing it right! As you know most of the customers “just want it working “ and don’t want the cost of a restoration. I’ve seen some serious failures throughout the years. Glad you’re showing folks how to do it correctly.
Less powerful but the power delivery difference is not relevant for typical listening. Otherwise it is very similar to the sound sig of the 8550 and 8650. This is a very sweet sleeper amp. I love it!
Going through the schematic .I noticed that they only use one just one big wattage drain resistor on the output vfets ..What is logic ..I thought the idea was to do some matching compensation as well as feedback ..So this means this trasistors have to be macthed in case of replacement .. Or just removed that big resistor and use two equivalent ones .ALso i noticed that this unit has a 54V plus or minus power supply ..In the TA 5650 the power supply is only 44v .SO yes this amp is capable of more power as you discovered ..
Yes, Sony uses ranks for matching their vfets. Related to the 5650: it delivers about the same power. I should have added that back in the day, vfets were plentiful and enough to get matched pairs. Today, not so much so a new designer would likely consider adding those resistors to share that current more efficiently amongst not so well matched transistors.
I have an entire Sony vfet manual set collected over the years. These manuals are difficult to obtain in original format but digital copies should be available on the net from sources such as the Hi-Fi Engine: www.hifiengine.com/manual_library/sony/tan-5550.shtml
@@atelier_HiFi thx for the reply, I'm still learning, did not realize that other models differed from the 5650 in that part of the circuit. Researching/restoring a 5650 and 3950SD currently
Hi! Great to understand a lot more regarding servicing these units. My concern is finding replacement V fets as Sony no longer have them ( sold all to Nelson Pass ) so I would think it is a risk buying anything V fet related. Having said that I have bought ( in transit ) the Sony TA 3200f amp and TA 2000f pre, condition supposedly good ?? My question to you , would it be worth buying back up units ( hopefully cheap :-) ) so to utilize the V fets as spares if ever needed ? Hope to hear back with your opinion, thanks .
@@atelier_HiFi Thanks, I plan to restore both but that doesn't answer my question, is it worth buying the same units as back up on the V fets transistors only ? As you well know these are no longer available, so if one goes, you are done for unless you buy another unit just for the V fets ! am I right ? thanks again.