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Sansui AU-X1

mjs1

mjs1

AK Subscriber
Subscriber
Hi folks:

Somehow, I've developed an obsession for the black-faced black-knobbed AU integrateds. I know, for example, that the AU 9900, 11000, 20000 are all great integrated amps and that the BA and CA amps and pre-amps separates are wonderful, but I am, for reasons that I can't understand, drawn to the black knobbed AU's. I started out with tha AU 717 and now have 3, 1 recapped. I now have one re-capped AU 919 which is fantastic. I can't imagine listening to anything better and it is in my main system. I have an AU D11 ii on the way (I hope) but haven't listened to one yet. In fact, I've only heard my 717s and 919, no other Sansui amps or receivers.

My question is has anyone had any experience with the AU-X1 (or for that matter the AU-G99X) and can they compare it to an AU-919? I want an AU-X1 I think mainly because of my obsession. It has somewhat more power but more total distortion than the AU D11 ii or AU 919. Can anyone give me any more rational reason to want one?

Thanks

Marc
 
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The AU-X1 has a reputation for being unstable; it oscillates and blows the output transistors which are unobtainium. Not every one of them has this problem so I suspect it is due to some change made during production, or it has the problem but it didn't get caught in early production runs. It is possible to correct the problem with some modifications. When the mods have been done it is a wonderful sounding amp, but no better than the AU-9900 (my personal favorite for sound and build quality. You know, for the money you would spend on an AU-X1 to buy it and then probably have it repaired and modified, you could buy an AU-9900 and paint the knobs black, or get them anodized black. Don't get so hung up on appearances. I think if you ever hear an AU-9900 you will want one.
 
dr*audio said:
I think if you ever hear an AU-9900 you will want one.
Click to expand...
I totally dig the looks of the professional and definition series gear. But I wonder, and doubt, that the 9900 would sound better than the 919. The 919 has a similar toroidal tranny and wpc at the 9900 but is a newer design. From what I've read I think the AU-D11 II is going to be better, meaning cleaner and more neutral sounding. I'd wait until you get a chance to listen to the D11 before I make anymore purchases.
 
mjs1 said:
Hi folks:

Somehow, I've developed an obsession for the black-faced black-knobbed AU integrateds. I know, for example, that the AU 9900, 11000, 20000 are all great integrated amps and that the BA and CA amps and pre-amps separates are wonderful, but I am, for reasons that I can't understand, drawn to the black knobbed AU's. I started out with tha AU 717 and now have 3, 1 recapped. I now have one re-capped AU 919 which is fantastic. I can't imagine listening to anything better and it is in my main system. I have an AU D11 ii on the way (I hope) but haven't listened to one yet. In fact, I've only heard my 717s and 919, no other Sansui amps or receivers.

My question is has anyone had any experience with the AU-X1 (or for that matter the AU-G99X) and can they compare it to an AU-919? I want an AU-X1 I think mainly because of my obsession. It has somewhat more power but more total distortion than the AU D11 ii or AU 919. Can anyone give me any more rational reason to want one?

Thanks

Marc
Click to expand...
A recapped au919 is indeed fantastic! I think this one of the biggest bargain in audio. If you do get the D11 ii could you kindly relay to us your impression and comparison to 919.
 
Thanks for the advice. The madness is passing, at least temporarily. I've read the threads in Classic Sansui on X1 instability and I suspect the surviving ones are ok, but, it helps to know that no one has yet told me the X1 is out of this world.
Warren, thanks for the advice on the AU 9900. I never thought of "Paint it Black". Duffinator and reggaenaut, a recapped AU 919 is indeed fantastic, I was wondering if whatever improvements came with AU 919 continued afterwards. I know that riverrat has an EchoWars recapped AU D11 ii and an AU 919 and that he prefers the D11, though the 919 is not recapped and I know from my AU 717's that recapping makes a big difference in how these amps sound, so the comparison is not totally fair. I'm sure that my AU 919 will outshine the stock D11 ii but hope, eventually to get this one recapped too so that I can make a fair comparison. I think that the D11 ii also has a reputation for some instability and recent threads on it, if I recall, state that there are 25 (I'm guessing) pots on it that need to be carefully adjusted. At present, if you can find one, the D11 ii is a better deal than the 919 coming in at about $250 vs $300 to $350 for the 919. The G99X goes for about the same as the 919, though I would guess that the 919 has the best build of the
group.

Thanks again.

Marc
 
Can anyone give me any more rational reason to want one?

Thanks

Marc[/QUOTE]

you mean this hobby is supposed to be rational?!?
 
I own:

AU-717
AU-9900
AU-D9

If push comes to shove the 717 wins....with the Loudness on (no offense anti-Loudness guys) it really punches! I just bought and recapped the D9. It is a really clean pure - sounding amp. Have not yet done a comparison with the 9900. I do not have the 9900 connected right now but it is so beautiful I can not seem to part with it.

I am interested in hearing the 919 now.
 
mjs1 said:
I know that riverrat has an EchoWars recapped AU D11 ii and an AU 919 and that he prefers the D11, though the 919
Click to expand...

To clarify, my AU-D11 II has NOT been recapped. Neither has my AU-919.

EW worked on my AU-819 before I got my AU-D11 II, and did a fine job on it. I thought the AU-D11 II sounded even better. I was ready to get it recapped, but got some conflicting info on this- AK member bigerik's tech friend tried some new caps in his AU-D11 II and thought the sound quality actually declined.

I also communicated at length with AK member quadbob, who found it very curious that an amp would sound worse with newer caps, he's rebuilt a couple of AU-D11 II's and told me that it's necessary to use the same type of high quality "low noise" caps as come in the original unit. This makes sense to me- I don't understand how new caps would make the amp sound worse unless there was some other mitigating factor.

My AU-D11 II is currently exhibiting some slight humming that doesn't come through the speakers, not sure what to make of that. Quadbob thought it was ripe for a recap, and I tend to agree. It is obviously not working at full potential, but still sounds very good to my untrained ears. I'm currently saving my pennies to have this done, if I can somehow kick my tuner collecting habit. I plan to put the EW refurb'ed AU-819 in place, but I've been swamped with work and haven't gotten around to it yet, and now I'm leaving for 15 days on the River.

Not being a tech, I'm easily confused by this conflicting info. I would love to hear your impressions of a direct comparison of refurb'd AU-919 vs AU-D11 II.
 
I have an AU-719 and an AU-G99X. I had an AU-919. I sold the 919 because it did not have the loudness function. I listen to a lot of lower level music. (wife).

I have not had a D11, but I believe it would sound like the G99X.

The G99X is a very clear, detailed, and accurate sounding amp. One of my favorites.

Rob
 
I found an AU-555 in one of the wholesale places here with knobs that had been painted black like that. The good thing was that because they had used paint that could be removed, it was reversible. If you anodize the knobs (assuming they are aluminum on the model you are considering, and not plastic), then you or any future owner will not be able to reverse/restore the color. Something to consider.
 
Au-x1 & 919

Hello mjs1,
I have a 919 setting on the floor beside me as I type. Mine is the newest (april 1980) off the line listed at audiokarma. I just took it off the shelf for some cleaning and adjustments. I have the very same obsession with the black-face sansui integrated amps as you do. Beauty is in the eye of the beholder! I don't believe that I could be happier with anything else (except the X1). But after reading about the problem with the X1 perhaps I'm better off without one. But, if you have the money for the mods needed and the right person to do the job, then go for it. The difference in sound in the 919 & X1 would probably only be what you get by having more pwr in reserve. These amps are of the same design philosophy from the same company at the same time. I had a factory sealed X1 on layaway in the early 80s but couldn't pay for it at the time ($850.) so I lost it. I'll never forget it.

My stuff...
SANSUI AU-919
TU-517
SOTA SAPPHIRE TURNTABLE
VANDERSTEEN SPEAKERS
ALL MONSTER CABLES
MONSTER HTS 1000 MK II CLEAN POWER.
 
WHEN it sounds, it sounds great, but often it doesn't sound at all, because it is unstable. When you are lucky you do not have to do the mods.

AU-X1 Stability Mods

Power amp section:
Replace the output transistors with Motorola transistors MJ21193/94.
Add a 100pF cap in parallel with C15 and C16.
Change C01 to 4700pF. (Keeps R.F. out of the input.)
mmPhono Amp section:
Add 1500pF in parallel with C15 and C16 (Stabilizes the amp)
Change R43 to a 330uF/63V electrolytic cap. Non polar is best, but not
necessary. Mount the - end toward R42.
This sets the gain at unity for DC. You don't want gain at DC in a phono amp; otherwise a warped record would blow the cones right out of your speakers. Also there is so much gain in the phono stage that if you allow gain at DC, the output drifts all over the place and you can't null out the DC on the output. It is capacitor coupled at the output, but the drifting DC gets through as very low frequency noise.
If you look at the output of the mm phono stage, it doesn't like to be
connected right up to a meter or a scope and it starts to oscillate. You must connect your meter or scope to it through a 1K resistor. I got it so it wouldn't oscillate by itself, but I couldn't get it to be stable into capacitive loads. Fortunately there is a 560 ohm resistor in series with the phono preamp output, probably for this very reason

I have never heard a "modded" one like above so I don't know how it sounds.

To give some advice:

start it up with the volume on zero, chance the source with volume on zero, never chance cables when the amp is "on".
If you don't have a turntable so you don't use "Phono", remove the phono boards.

I have 4 of them.
 
The above notes on the mods are mine, and the amp does sound wonderful afterwards. Anyway it sure beats having it go up in a puff of smoke! Baiscally if you find an AU-X1 that still works properly, it probably doesn't need the mods. Most of those that do are probably in closets under a pile of stuff and smell like burnt circuit boards.
 
Sansui AU X1

Thank you all for the responses. For the time being, I'll concentrate on the AU D11 ii. If it ever comes I'll post my impression. I'm sorry that riverrat is having trouble with his and that I misquoted him. My interpretation of these posts is that the AU X1 is obviously a great amp, that one that is still working is probably a stable later model, that any of these Sansui integrateds (X1, 9900, 919, G99X, D11, and others) especially when brought up to spec will sound great and that in a blinded test it may be difficult to choose between them. Our preferences are colored by what we have and have grown to love. If an AU X1 becomes available at the right time and I can afford it I might go for it, but this will be because of my obsession, not because of the music. You can all rest assured, however, that if I do get interested in a 9900, I will not paint or anodize the knobs.

Marc
 
Good luck finding one. Their pretty rare but they have fantastic specs. I've never owned one or heard one but I'd love to hear one.
 
Hi folks,

I have two AU-X1 in a vertical bi-amping constellation, a modded and aligned TU-X1, two CA-F1, three BA-F1 (for homecinema use), CA-3000, AU-D9, AU-710 (=717), AU-517, AU-317 and two TU-717, C-2102/B-2102.

Among all AUs I know the X1 certainly is the best, especially the power amp which sounds even stronger and faster than most separates from Sansui. Bass is by far better than that from a BA-F1 or 2102. A beast of its own class.

Mine are stable, maybe because they have original parts and are later and – maybe Sansui-fixed – European models.

Best buy for me is the 717 series - still unbelievable good for the money.

The D9 is clean-sounding, but it has not the punch of a 717.

Best regards


Tom Frantzen, editor, STEREO magazine, Germany
 
Hi Tom

Hi Tom

I know of you from various posts over the internet. I have two questions for you if you're still following.

1. What kind of preventive maintenance, if any, do you do on your AU-X1 or other vintage gear? Do you check specs on them on a fixed schedule, replace parts at any specific time, or just use them until there is a problem?

2. The best Sansui amp that I currently own is an AU-919. Do you have any experience with this amp, is it comparable to your CA-F1 BA-F1 combination, and how does the AU-919 or CA + BA F1 compare with the AU-X1 and 717?

I guess these are more than two questions. Thanks and best wishes.

Marc
 
Hi Marc,

I use them until there is a problem, but there wasn't and isn't any. In case of emergency I have the opportunity to have them examined in the STEREOlab, of course.

Before any audition I move the mode switch (integrated/pre/main) and the level knobs to avoid distortion through contact failures.

The TU-X1 has been modded and – in case of antenna input/frontend - redesigned by Reinhard Wieschhoff, one of the best Tuner designers worldwide (Klein+Hummel, Restek). All caps in the FM section are new, the complete tuner was aligned and optimized. Selectivity, channel separation, THD, overall precision and above all sensitivity now is by far better than any TU-X1 "new out of the box". The sound is marvelous..

As far as I know the CA-F1/BA-F1 is rather similar to the AU-919 (as CA-3000/BA-3000 and AU-20000) and I like the sound very much.

I also like the AU-X1 as integrated amp, but this one is rather a power amp with inputs and volume control, you know. For some time I used the - warmer sounding - CA-F1 (or two :-)) together with the X1s which I slightly prefered to the neutrality of AU-X1 alone. Now besides the Sansui preamps I have a Carver C-4000t and a GAS Thaedra, because I think Bob Carver and Jeames Bongiorno both are incredibly good amp designers.

The power amp of the AU-X1 is a class of its own still rivaling some very expensive new stuff. Fortunately this extremely fast beast is stable yet. I think the speed and power is the secret of this amp.

I already wrote that AU-X1 outperforms any of the mentioned in case of bass response, control, 3d and overall dynamics. But I like the 717 very much, because you can get it for little money and have an amp to die for.

We had one here in the publishing house for some weeks and there were some well-known challengers which were clearly beaten by this 30 year old black knight...

In my opinion the older Sansuis (AU-9900, 11K, 20K or G-33000, even the amp combos) sound good but are runners-up to the vivid sound of a 717, 919 or X1. When it came up in 1978 the 717 is said having outperformed fat phase linear combos as well.

And the later Sansuis like my AU-D9 may be slightly sweeter, but in my opinion also quite harmless...

Fortunately I got all my Sansui stuff (also equalizer, reverb amp, timer a.s.o.) rather cheap and before it became cult.


Best regards



Tom
 
Hi,

of course from time to time I clean contacts, I switched from 220 to 240 volts (in Germany we have 230 volts since 1987) and I use low-inductive loudspeaker cables (Supra Sword 3.0 from Sweden). But that's it.

I bought the first AU-X1 around 1996 and got the second as birthday gift from my wife around 1999/2000. The last AU-X1 were sold in 1982/83, so they are around 25-28 years old.

Vertical biamplification means that each of both AU-X1 feeds only one channel, one complete loudspeaker (bass and high/midrange section).

Horizontal biamplification means that one amp feeds the bass drivers of both channels and the other the high/midrange drivers of both channels.

We measured slightly more than 200 watts into 8 ohms load and 315 watts into 4 ohms load, 420 watts for short time (impulse), each channel (THD 1%).

We also measured a AU-517 and BA-F1 some years ago and the data still were well within specification, power far above the rated figures.

BA-F1 was 158 watts into 8 and 210 watts into 4 ohms (THD 1%). This is what you can expect out of a 919 as well.

Tom
 
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