Très bel appareil, très bien construit, du haut de gamme, comme Sansui savait le proposer. Quel dommage que cette marque ait disparu, vous nous démontrez les merveilles qu'elle savait construire, à des coûts relativement peu élevés, ce qui a peut être anéanti cette marque. Merci pour ce beau reportage, et je souhaite une très longue vie à ce magnifique appareil, entre les mains d'un passionné ! 😉
Very interesting video, thank you for that. Some (hopefully helpful) comments. I think I would have thrown away the copper plate that sandwiches between the output transistors and the heatsink. It can not help with anything but it does introduce another heat transfer interface. Yes, I know copper is better than aluminium as a heat conductor, but here its advantage I reckon would be totally offset by the extra exchange interface it is introducing. Now if the entire heatsink were copper....mmmmm, copper.....(it would have probably doubled the price of the amplifier). I would have also fly cut the heatsink where the output transistors lie on the heatsink to take off a skim of material and bring it to perfect flatness (if you ever do that you will find out how uneven these extruded heatsinks are; you can also see where the screws have pulled up the heatsink surface when tightened - a small countersink would fix that). Fly cutting is not that easily done, I accept, not everybody has a milling machine lying about but it is totally worth it in my experience. Just 0.1mm is enough and it leaves a mirror finish yonks better than the extruded surface. The anodising is again not helping so it is an extra (if minute) bonus. Much better to have the exposed Aluminium surface. And I would have lapped the output backs on fine sandpaper. You can see some of them have the plastic covering the metal at the back a bit. That will keep the metal up instead of allowing it to contact the heatsink surface. The top copper plate is a good idea, no problems there. It helps with distributing the clamping force and maybe evens out the temperature a bit. If there was enough room, I would machine one from thicker flat stock and put some fins on it. The back plates on all transistors like that are copper, they just get a coating of tin or something else to prevent oxidation. So are capacitor terminals, those are mostly tinned, but if you cut them and look in the cut you will see the copper red.
Great work on this thing. What a gorgeous amplifier inside and out. Even the leads of the capacitors and semis are copper. Really shows how much time and effort Sansui invested into their flagship pieces. Nothing like this will ever come from a “consumer” company ever again. Need to find myself a Flagship Sansui from this era!
I have to say, that is much fancier in parts and construction than I was expecting before you opened the hood. Pretty cool unit. Those 10uF caps are wild!
The copper plate that goes in between the ouput devices and the heatsink is a bit pointless IMO because it introduces another thermal interface. If it was considerably bigger and screwed to the heatsink in several places then it would be an advantage but I'm just nit picking because it's an otherwise beautifully designed and built amplifier. Thanks for the videos.
I completely agree it seems utterly pointless. The only reason I could think of why it was done was to create a faster thermal matching between the outputs before the heat is dissipated into the main heatsink. Regardless leaving it original was the only way to go other than moving to thermal pads.
Amazing amp fast amp Prime hifi Conor just master restored and resto modded my Au717 it sounds amazing !! Everything was changed out !! Tha KS for the video Conor used all Nippon chemicon and nichicon muse Kemet
@@whatcouldgowrong7914 thank you very much for sharing the information. I have a Sansui AU-717 and Sansui 5050 receiver which I plan to restore soon. Both of those units have that corrosive glue on the board.
There should be plenty of options but I cannot advise what to use sorry as I’ve never replaced them. They’re TO-3P package so you will need to match specifications but nothing current is a direct match for them being bespoke exotic parts
Honestly it is probably the best and has dethroned everything else I have… Not just from build quality but overall sound, it seems as clean as my best performer (Topping LA90) with 3x the power. A full review will come soon once the calibration and restore is finished so it can benchmark at it’s best 👌
@@whatcouldgowrong7914 Wow that is something, they really built this Sansui to the best possible they know how. I am a fan of vintage Sansui myself. I have AU-D11 and for some reason I always go back to it.
@@rolandd5397 It is definitely a nice surprise as I thought Sansui were done by the 90s. Competing with modern offerings is no small feat either when it comes to noise floor and just general clean sound.
So if everyone seems to be down on elna capacitors ,saying they're no good, why would Sanusi use them ? I guess some of the so called experts are wrong ?
No idea where the hate for ELNA comes from, I have only ever seen 2 bad ones and they were cooked in a bad location. ELNA are class leading capacitors and test better than the new ones I replace them with most of the time…
25:45 It doesn't matter anymore, but the left plate was the other way around with the notch on the left bottom, you can see how it was at 9:50. Maybe the reason the holes didn't seem to line up well.
Très bel appareil, très bien construit, du haut de gamme, comme Sansui savait le proposer. Quel dommage que cette marque ait disparu, vous nous démontrez les merveilles qu'elle savait construire, à des coûts relativement peu élevés, ce qui a peut être anéanti cette marque.
Merci pour ce beau reportage, et je souhaite une très longue vie à ce magnifique appareil, entre les mains d'un passionné ! 😉
Very interesting video, thank you for that.
Some (hopefully helpful) comments.
I think I would have thrown away the copper plate that sandwiches between the output transistors and the heatsink. It can not help with anything but it does introduce another heat transfer interface. Yes, I know copper is better than aluminium as a heat conductor, but here its advantage I reckon would be totally offset by the extra exchange interface it is introducing. Now if the entire heatsink were copper....mmmmm, copper.....(it would have probably doubled the price of the amplifier). I would have also fly cut the heatsink where the output transistors lie on the heatsink to take off a skim of material and bring it to perfect flatness (if you ever do that you will find out how uneven these extruded heatsinks are; you can also see where the screws have pulled up the heatsink surface when tightened - a small countersink would fix that). Fly cutting is not that easily done, I accept, not everybody has a milling machine lying about but it is totally worth it in my experience. Just 0.1mm is enough and it leaves a mirror finish yonks better than the extruded surface. The anodising is again not helping so it is an extra (if minute) bonus. Much better to have the exposed Aluminium surface.
And I would have lapped the output backs on fine sandpaper. You can see some of them have the plastic covering the metal at the back a bit. That will keep the metal up instead of allowing it to contact the heatsink surface. The top copper plate is a good idea, no problems there. It helps with distributing the clamping force and maybe evens out the temperature a bit. If there was enough room, I would machine one from thicker flat stock and put some fins on it.
The back plates on all transistors like that are copper, they just get a coating of tin or something else to prevent oxidation. So are capacitor terminals, those are mostly tinned, but if you cut them and look in the cut you will see the copper red.
Great work on this thing. What a gorgeous amplifier inside and out. Even the leads of the capacitors and semis are copper. Really shows how much time and effort Sansui invested into their flagship pieces. Nothing like this will ever come from a “consumer” company ever again. Need to find myself a Flagship Sansui from this era!
It is definitely a forever amplifier for me, requires a lot of care in calibration but the high water mark for Sansui and audio excess for sure 🙏
I have to say, that is much fancier in parts and construction than I was expecting before you opened the hood. Pretty cool unit. Those 10uF caps are wild!
Designed to last forever
The copper plate that goes in between the ouput devices and the heatsink is a bit pointless IMO because it introduces another thermal interface. If it was considerably bigger and screwed to the heatsink in several places then it would be an advantage but I'm just nit picking because it's an otherwise beautifully designed and built amplifier.
Thanks for the videos.
I completely agree it seems utterly pointless. The only reason I could think of why it was done was to create a faster thermal matching between the outputs before the heat is dissipated into the main heatsink. Regardless leaving it original was the only way to go other than moving to thermal pads.
What a brilliant lady.
Amazing amp fast amp Prime hifi Conor just master restored and resto modded my Au717 it sounds amazing !! Everything was changed out !! Tha KS for the video Conor used all Nippon chemicon and nichicon muse Kemet
Impressive work. Can you please share the name of the glue remover you use?
Toluene or carby / throttle body cleaner seems to do the job but use it sparingly as it can attack plastics etc
@@whatcouldgowrong7914 thank you very much for sharing the information. I have a Sansui AU-717 and Sansui 5050 receiver which I plan to restore soon. Both of those units have that corrosive glue on the board.
@@johndcosta1259 best to dab it on the glue and let it sit, the glue should turn to a gel eventually once you break the top layer.
whats the substitute for these output transistors?
There should be plenty of options but I cannot advise what to use sorry as I’ve never replaced them. They’re TO-3P package so you will need to match specifications but nothing current is a direct match for them being bespoke exotic parts
What voltage does it run on? Here where I live we've got 230 volts, will it work?
Most Sansui Alphas are 100v only as they were only sold in the Japanese domestic market. You can easily run it with a stepdown transformer :)
great job !
How does it sound compare to the best amplifier you have in your opinion?
Honestly it is probably the best and has dethroned everything else I have… Not just from build quality but overall sound, it seems as clean as my best performer (Topping LA90) with 3x the power. A full review will come soon once the calibration and restore is finished so it can benchmark at it’s best 👌
@@whatcouldgowrong7914 Wow that is something, they really built this Sansui to the best possible they know how. I am a fan of vintage Sansui myself. I have AU-D11 and for some reason I always go back to it.
@@rolandd5397 It is definitely a nice surprise as I thought Sansui were done by the 90s. Competing with modern offerings is no small feat either when it comes to noise floor and just general clean sound.
with Sansui an even better choice will be the power amplifier, they are stronger on the bass. e.g. B 2301 or B 2102 MOS VINTAGE
@@Sansui1000A one day maybe if I cross paths with one
So if everyone seems to be down on elna capacitors ,saying they're no good, why would Sanusi use them ? I guess some of the so called experts are wrong ?
No idea where the hate for ELNA comes from, I have only ever seen 2 bad ones and they were cooked in a bad location. ELNA are class leading capacitors and test better than the new ones I replace them with most of the time…
25:45 It doesn't matter anymore, but the left plate was the other way around with the notch on the left bottom, you can see how it was at 9:50.
Maybe the reason the holes didn't seem to line up well.
I tried both ways around assuming that's why also but it still didn't line up properly without forcing it, anyways it was fine in the end :)
class H amp?
Class AB with a generous bias but also uses bridged amplifiers per channel (hot side amplifier + cold side amplifier)