Sansui au-x1

Nice Toni :thmbsp:

Yeah I could scan at 600dpi , but one page alone would be 10mb.
Like this one


And AK's limit is 20mb for the whole file. Toni had to compress pdf's so it would end up to 20mb.

Sorry, unreadable!! AK is junk, if they can not allow for a hi-res schematic or SM, thus need to find another method to share this information. You are able to submit a hi-res schematic to hifiengine, they have accepted what I submitted for other gear. They even merged a two page schematic, done a great job of it, they have pdf sw that I do not have access to.
BTW, i assume you own a AU-X1, what do you think of it, looks to be a bitch to fix!!
Cheers
Rick

As for the AK I can't really comment.
As for AU-X1 I don't own one though I'd love to. It's really difficult to find a mint one ,with the op devices intact. Once I had the chance but no money. So the bird is gone. Still looking though.
It's not a bitch to fix , it just needs the correct technician to handle it. If you don't mess it up, it will not by it self. I have heard the stories about oscilation and all that stuff.
If you find one get it and you'll see how a unique amp sounds.

http://www.ebay.com/itm/301287069076?_trksid=p2055119.m1438.l2649&ssPageName=STRK:MEBIDX:IT

it just needs the correct technician to handle it.

Click to expand...

And are you or do you know of one?
What do think it would go for, if it was running fine.
So many have blown outputs, what does that tell you?
I consider myself to be a capable EE, it still looks like a bitch to fix, due to the fact that everything is tightly packed. If the pcb's are not connectorized, it is even worse. With designs like this, it is better sometimes to make a test jig for every circuit card, outside of the unit. I could well image what I would charge to fix one of these, there are very few that have worked on them and have reported in this forum. I am not one of them so each is an experience.
Like I need another project to work on at thsi point in time.
I know of another dead one on Canuck audio mart.
I simulated the PA in LTspice, it is marginally stable, tamed it down with a bit more compensation as a few have written. Over all, other ways to do the same thing in ckt design.
Only know for sure, if I have one in front of me.
No tone controls No adapter loop.
Stupid DC coupling, like it makes a difference, one capacitor.
I would only buy one because of the pre-amp section, looks as good as a few Yamaha designs.

Cheers
Rick

rcs16 said:

http://www.ebay.com/itm/301287069076?_trksid=p2055119.m1438.l2649&ssPageName=STRK:MEBIDX:IT


And are you or do you know of one?
What do think it would go for, if it was running fine.
So many have blown outputs, what does that tell you?
I consider myself to be a capable EE, it still looks like a bitch to fix, due to the fact that everything is tightly packed. If the pcb's are not connectorized, it is even worse. With designs like this, it is better sometimes to make a test jig for every circuit card, outside of the unit. I could well image what I would charge to fix one of these, there are very few that have worked on them and have reported in this forum. I am not one of them so each is an experience.
Like I need another project to work on at thsi point in time.
I know of another dead one on Canuck audio mart.
I simulated the PA in LTspice, it is marginally stable, tamed it down with a bit more compensation as a few have written. Over all, other ways to do the same thing in ckt design.
Only know for sure, if I have one in front of me.
No tone controls No adapter loop.
Stupid DC coupling, like it makes a difference, one capacitor.
I would only buy one because of the pre-amp section, looks as good as a few Yamaha designs.

Cheers
Rick

Click to expand...

It doesn't need tone controls , like any serious amp.
Dc coupling is not stupid. Its the best way to couple a pre amp to the power amp. And yes a capacitor can make a difference. Specially if it's in signal.
Pre amp and power amp on au-x1 are very well designed and very fast. Neutral also. Don't compare apples to peaches, they are different fruits.

Dc coupling is not stupid. Its the best way to couple a pre amp to the power amp. And yes a capacitor can make a difference. Specially if it's in signal.

Click to expand...

Yes the choice of capacitor can make a difference, meaning that a good quality cap may not make any difference. You can see that Sansui usually put a film cap(0.22-0.47uF) across a large ecap, as they thought that this would improve the sound quality of the design.
If you look closer at the AU-X1 schematic, you will see that all the sub-ckts are AC coupled on the outputs, MC head amp(F-2917), MM head amp(F-2770), flat amp(F-2819). If they wanted to make the design truely DC coupled, they would have removed the o/p coupling caps and used DC offset trimmers or better yet DC servo's. I think CA-F1 does this!
So, like I said it is stupid and a marketing gimmick only

Kewl

May I get a copy of that please?

Whats the date on it btw?

Does it have info on the newer version of the phono stage main board? That would be nice to finally have. :yes:

There's no date on it. What about newer version phono stage? Are you referring to au-x11?

AU-X1 later version

The AU-X1 dramatically change the F-2772 MC, MM Mother Circuit Board from its first iteration.

The first version was a bit of a mess. The revised version was a reaction to the oscillation problems that the fist version propagated.

The first version (ala Mr Dale)







Below is a picture of a recapped Second / Later version



Although...come to think of it...I suppose this new version would have been addressed in a service bulletin rather than making a change to the basic service manual.

Many thanks !!!!

Ok I see what you mean, yes there was a service bulletin for the revised version , to address the supposed oscillation problems, but that was only a bulletin . Sadly I didn't kept a copy of it. The manual I scanned refers to the first photo you posted , with two lytics among the relays.

Speaking of revisions and upgrades.
Did you know Sansui made a revision/upgrade for the E.Q. amp circuit board F 2770/1?
It wasn’t just a revision or upgrade but they designed a complete new E.Q, amp circuit board F 3451/2.
I think they designed it after the AU X1 was out of production(see the date 10-13-83)

No I wasn't aware of this.

Nicowico said:

Speaking of revisions and upgrades.
Did you know Sansui made a revision/upgrade for the E.Q. amp circuit board F 2770/1?
It wasn’t just a revision or upgrade but they designed a complete new E.Q, amp circuit board F 3451/2.
I think they designed it after the AU X1 was out of production(see the date 10-13-83)

Click to expand...

Two years late....but...DANG!!
That info is amazing to learn. X11 boards CAN be used in X1.

I always suspected that was possible.

Well yeah , the x11 was the successor to x1, with minor refinements and stupidly decrease the amount of output devices to 4 per channel instead of 6 X1 had.