It's been a while now. I got the parts around 2 weeks ago, but always struggled to find time to post back on how it went.
Technics SU8600:
Since the unit was pretty clean, I just used some compressed air from the compressor to blow off some dust inside. Did the whole recap using Elna Silmic 2 everywhere I could, Nichicon Fine Gold where I couldn't fit the Silmics and Nichicon Muse (green) for bipolars, and 1 or 2. For the big power supply caps 15000uF, I went for CDE 383LX (Cornell Dubilier Electronics, 4 pin version). Resistors also got swapped at the same time, in total 4 resistor that were recommended to swap out. Since it was all apart, I also got rid of the old thermal grease and used some fresh Arctic Cooling MX-4 (not conductive electrically, so it no problems here). Adjusted BIAS after all of the work was done. All in all, pretty happy how it turned out. Looks clean and nice inside now. Sounds fine to me, maybe just a tiny bit better, but not by much. I did check the resistors and almost all capacitors that went out of the unit. Resistor did show the correct values, so I guess it was just visually broken. I found 3-5 capacitors that were "really" bad, by this I mean high impedance and uF was far off. Others did show pretty okay stats, and could have worked further I guess. While I still feel safer knowing that not much can happen to this unit longer.
Sony F808ES. Swapped all of the fusibles that were in the manual, except 2 (forgot to order some extra...) and also did a partial recap (EQ, Power A and Power B section without big 15000uF caps). Why did I swap fusibles knowing that the unit still works fine? Well, I thought that they were bad and was the problem of the high heat. All of the fusibles that went out, did measure fine (I start to think that my tester is just bad
). Recap was done to make it look a bit nicer visually, since you could see some of the caps from the top of the unit, and they had this corroded top. I chose to go for Elna Silmic 2 and Nichicon Fine Gold in some places. Surprisingly I found some 2 Muse (polar) caps in Power B section that were far off the spec. Other, even though they looked bad, were measuring pretty okay. After all of the servicing, I readjusted the BIAS and went for a listen. To be honest, I really enjoyed how it sounded now. Was more open, and clean without any adjusting of bass or treble. I always wanted to up the treble on my speakers, but now it just gave a wonderful sound. Heat problems weren't solved even after the fusible swap, nor the thermal grease solved it. It was heating less, but still pretty warm. I guess it's just the design of that amp? Anyway, it's sold now. Would have kept it if the heating problems went away. Not a fan of the warm amplifiers, and since I have the Technics (above) that I prefer, it's totally ok. I think the new owner should be happy having almost fully recapped unit for a great price.
JVC R-X303V is doing great now too. Did a recap here also + changed some resistors, that looked a bit bad. Works like charm now, but is not the amplifier I enjoy listening. Hope to get it sold soon.
Got some other projects coming on it's way also. I finally got my hands on one Nikko amplifier that is 100wpc 8ohm. Not a heavy one, and with a simple desing, NA990. Sounds pretty great, but something feels a bit off. It is from the 1981 (I think), and could use some help. Got it for cheap, and will be keeping it for some time, just in case I need an extra amplifier somewhere. Opened it up, looks pretty clean too, but there is signs of someone being in there. One of the power supply caps is swapped with the newer and bigger one (size, not uF), and looks ugly. Will be doing full recap on this unit, making it look pretty. Doing it with the Panasonic FR, FC and FS caps this time. Just for the testing and experimenting purposes, to see if the "audio grade" caps, really do anything better... Will use some United Chemi-Con SMH for power supply here (10000uF also).
Another thing I got also hands on in between, was a Spark SC8 vacuum tube preamp. Pretty solid build, weight around 8kg. There is 4 tubes, not sure what type. Using it with a NAD C270 (solid state amp without pre). Sounds really good on some music, especially with instruments. Not that great with all the "pop" and "radio" type music. Lack of the bass and treble adjustment on the preamp is sad, but I feel like NAD might be the issue here. Did try to power the preamp using my technics as amp, and it had more bass and treble. I have read many times that NAD used some crappy caps in these units, so I opened it up and did some inspecting. 2 of the 4 power supply caps (10000uF) look deformed/bulged a bit at the top. Some other caps also look strange, might be I'm wrong. Looks like some of the resistors also might be bad, look a bit burned (around the leads). Ordered a full recap for this also + some resistors. Went for the same caps as Nikko amp (FR, FC, FS and SMH). I have two of these NADs, so it will be easier comparing a recapped and not recapped.
Technics SU8600:
Since the unit was pretty clean, I just used some compressed air from the compressor to blow off some dust inside. Did the whole recap using Elna Silmic 2 everywhere I could, Nichicon Fine Gold where I couldn't fit the Silmics and Nichicon Muse (green) for bipolars, and 1 or 2. For the big power supply caps 15000uF, I went for CDE 383LX (Cornell Dubilier Electronics, 4 pin version). Resistors also got swapped at the same time, in total 4 resistor that were recommended to swap out. Since it was all apart, I also got rid of the old thermal grease and used some fresh Arctic Cooling MX-4 (not conductive electrically, so it no problems here). Adjusted BIAS after all of the work was done. All in all, pretty happy how it turned out. Looks clean and nice inside now. Sounds fine to me, maybe just a tiny bit better, but not by much. I did check the resistors and almost all capacitors that went out of the unit. Resistor did show the correct values, so I guess it was just visually broken. I found 3-5 capacitors that were "really" bad, by this I mean high impedance and uF was far off. Others did show pretty okay stats, and could have worked further I guess. While I still feel safer knowing that not much can happen to this unit longer.
Sony F808ES. Swapped all of the fusibles that were in the manual, except 2 (forgot to order some extra...) and also did a partial recap (EQ, Power A and Power B section without big 15000uF caps). Why did I swap fusibles knowing that the unit still works fine? Well, I thought that they were bad and was the problem of the high heat. All of the fusibles that went out, did measure fine (I start to think that my tester is just bad
). Recap was done to make it look a bit nicer visually, since you could see some of the caps from the top of the unit, and they had this corroded top. I chose to go for Elna Silmic 2 and Nichicon Fine Gold in some places. Surprisingly I found some 2 Muse (polar) caps in Power B section that were far off the spec. Other, even though they looked bad, were measuring pretty okay. After all of the servicing, I readjusted the BIAS and went for a listen. To be honest, I really enjoyed how it sounded now. Was more open, and clean without any adjusting of bass or treble. I always wanted to up the treble on my speakers, but now it just gave a wonderful sound. Heat problems weren't solved even after the fusible swap, nor the thermal grease solved it. It was heating less, but still pretty warm. I guess it's just the design of that amp? Anyway, it's sold now. Would have kept it if the heating problems went away. Not a fan of the warm amplifiers, and since I have the Technics (above) that I prefer, it's totally ok. I think the new owner should be happy having almost fully recapped unit for a great price.JVC R-X303V is doing great now too. Did a recap here also + changed some resistors, that looked a bit bad. Works like charm now, but is not the amplifier I enjoy listening. Hope to get it sold soon.
Got some other projects coming on it's way also. I finally got my hands on one Nikko amplifier that is 100wpc 8ohm. Not a heavy one, and with a simple desing, NA990. Sounds pretty great, but something feels a bit off. It is from the 1981 (I think), and could use some help. Got it for cheap, and will be keeping it for some time, just in case I need an extra amplifier somewhere. Opened it up, looks pretty clean too, but there is signs of someone being in there. One of the power supply caps is swapped with the newer and bigger one (size, not uF), and looks ugly. Will be doing full recap on this unit, making it look pretty. Doing it with the Panasonic FR, FC and FS caps this time. Just for the testing and experimenting purposes, to see if the "audio grade" caps, really do anything better... Will use some United Chemi-Con SMH for power supply here (10000uF also).
Another thing I got also hands on in between, was a Spark SC8 vacuum tube preamp. Pretty solid build, weight around 8kg. There is 4 tubes, not sure what type. Using it with a NAD C270 (solid state amp without pre). Sounds really good on some music, especially with instruments. Not that great with all the "pop" and "radio" type music. Lack of the bass and treble adjustment on the preamp is sad, but I feel like NAD might be the issue here. Did try to power the preamp using my technics as amp, and it had more bass and treble. I have read many times that NAD used some crappy caps in these units, so I opened it up and did some inspecting. 2 of the 4 power supply caps (10000uF) look deformed/bulged a bit at the top. Some other caps also look strange, might be I'm wrong. Looks like some of the resistors also might be bad, look a bit burned (around the leads). Ordered a full recap for this also + some resistors. Went for the same caps as Nikko amp (FR, FC, FS and SMH). I have two of these NADs, so it will be easier comparing a recapped and not recapped.
If you have any photos of the Sony, I wouldn't mind seeing them here too.
). 
