Fixed it. That’s the good part.
The less good part is that I have no idea what was wrong. The connector L/M going to the protection circuit 02/04 was loose and after fixing that the amp worked. I have no explanation for that.
As for the sound, it is very detailed and the amp separates the instruments fairly good.
But I find it aggressive in the mids. I prefer the smoother and more musical sound of the AlephX which I compared it with.
Also, the BA3000 sounds nicer to my ears.
It has however impressive specs, is very well build and is still perfectly well aligned.
I found 1.2mV offset and the bias was still 18mV instead of 20mV after all these years.
I leave it to EchoWars to post the link as the effort to upload it was his.
/Hugo
The less good part is that I have no idea what was wrong. The connector L/M going to the protection circuit 02/04 was loose and after fixing that the amp worked. I have no explanation for that.
As for the sound, it is very detailed and the amp separates the instruments fairly good.
But I find it aggressive in the mids. I prefer the smoother and more musical sound of the AlephX which I compared it with.
Also, the BA3000 sounds nicer to my ears.It has however impressive specs, is very well build and is still perfectly well aligned.
I found 1.2mV offset and the bias was still 18mV instead of 20mV after all these years.
I leave it to EchoWars to post the link as the effort to upload it was his.
/Hugo
Attachments
Hi lumanauw,
Other amps that use a "diamond transistor" type output stage are Marantz 300DC, 170DC and possibly the 240 (I'd have to look). The Nakamichi 620 is also done a similar way. This Sansui is a little different though.
The "signature" of this design is wonderful detail, the most delicate sounds are presented beautifully. I've been working on a variation of this for a few years. A BUF634 is a good model.
Hi Hugh,
Aggressive mids and messy highs can usually be blamed on ceramic capacitors. Bypassing electrolytics with film caps will also help a lot also. Since this is not your amp, out the door she goes!
You might want to do some careful resoldering. This would not surprise me as I've had similar things happen with units this old. I have learned that odd things can happen with old wave soldered joints. Soldering by hand does stand the test of time. Use a touch of flux and clean the board afterwards.
-Chris
Other amps that use a "diamond transistor" type output stage are Marantz 300DC, 170DC and possibly the 240 (I'd have to look). The Nakamichi 620 is also done a similar way. This Sansui is a little different though.
The "signature" of this design is wonderful detail, the most delicate sounds are presented beautifully. I've been working on a variation of this for a few years. A BUF634 is a good model.
Hi Hugh,
Aggressive mids and messy highs can usually be blamed on ceramic capacitors. Bypassing electrolytics with film caps will also help a lot also. Since this is not your amp, out the door she goes!
You might want to do some careful resoldering. This would not surprise me as I've had similar things happen with units this old. I have learned that odd things can happen with old wave soldered joints. Soldering by hand does stand the test of time. Use a touch of flux and clean the board afterwards.
-Chris
I do also have this Sansui BA-F1 beast, really great.
I did have problems on power supply, as i saw it have two voltage comming, symetrical for main power, and symetrical thrue soem transistors on power supply board, I did set everything except I have distorzion on one channels, and i don't have original output transistors because somebody RIP them.....
Also if someone have schematic of amplifier part can be uploaded here or emailed?
thanks!
I did have problems on power supply, as i saw it have two voltage comming, symetrical for main power, and symetrical thrue soem transistors on power supply board, I did set everything except I have distorzion on one channels, and i don't have original output transistors because somebody RIP them.....
Also if someone have schematic of amplifier part can be uploaded here or emailed?
thanks!
