New addition: Sansui AU-555A

[kray]

Just got this beauty today. I have a AU-101 that was recapped from a fellow AK’er and fell in love so decided to look for a little beefier model. After my research and availability I picked this 555A. Cosmetically it’s 9/10. All original, came in original box with all original paperwork. Was told it sat in the box most of its life. Since this will be my daily driver, I’m now on the waitlist for the infamous Leestereo to completely upgrade this sucker!

It’s no slouch at all now. Very “airy” with lots of detail.

 

[BLAH BLAH]

Wow that box the Sui 555A was packed in is pristine! Must speak volumes for the state of that 555A...

 

[kray]

Wow that box the Sui 555A was packed in is pristine! Must speak volumes for the state of that 555A...

I think they correlate perfectly!

 

[911s55]

Whoo hoo, nice one! Glad you found and excellent cosmetic unit, makes the added restoration investment worth even more.

I've rotated six different amps since getting my new Zu Dw's a few weeks ago and the 555a is the sweet spot. I hope you dig it.

 

[kray]

Whoo hoo, nice one! Glad you found and excellent cosmetic unit, makes the added restoration investment worth even more.

I've rotated six different amps since getting my new Zu Dw's a few weeks ago and the 555a is the sweet spot. I hope you dig it.

Thanks! For sure makes the restore cost worth it to have it so minty box and all. So far loving it with the Zu’s

 

[kray]

It’s like a found a treasure

I just not tipped the amp over on its side and found this

 

[Sansuiman]

Wow, that is a sweet find. I have to admit being slightly envious. Only component I've ever scored mint and in a box that clean is a TU-719 tuner (which is nice, no doubt) and I've been at it since 1996. Have a few other things with boxes that are beat up to varying degrees.

Anyway, you did quite well in picking that up, considering the 555A is a real sleeper. Of course, word of it's worthiness is becoming common knowledge now, so they are commanding real money in most cases. If you ever sell it, it will fetch a premium being so complete and clean.

An unrelated side note, anyone else ever notice the boxes have a silhouette of the carved wood used in making their speaker grilles? I've seen this on many Sansui boxes of the early 70's, and am wondering if they reused big sheets of cardboard that the raw speaker grille lattice was packed in to make shipping cartons. Can't really see how else that would happen, as I don't think they'd spend extra money and effort to "print" that pattern on the boxes just for looks? Anyone else have insight on that?

 

[kray]

Thanks @Sansuiman

I agree with you. Also I did notice the speaker grill imprint on the boxes. Interesting theory about that.

 

[BLAH BLAH]

Tad curious about those so called speaker grill imprints on the Sui boxes myself...
Hunted down one of my 555A boxes (serial number 223109433 stamped on the box) seems like their are faint 'v' marks on the top
But am having trouble seeing any 'v' pattern on the sides. Not sure whether it's because their completely faded, my eyes are in a worse state than I realize or their were none...

 

[nosirrah]

Very nice indeed. Find a TU 666 tuner to match and enjoy. I have that setup in my bedroom, it probably logs more time than any other here.
Great sound, ample power, looks great!

 

[Sansuiman]

Blah Blah, I definitely see the markings on the box top. Have to figure the sides have faded (or darkened rather as corrugated is prone to do with age) making it less or non-visble.

This is getting OT, but I'd love to know why this shows up on so many boxes. I really have to think bulk sheet pieces of speaker lattice were shipped in this cardboard (maybe the cardboard was between layers in a master crate as padding) as Sansui used an outrageous amount of that grille material given the number of speakers that were made with that design.

So, I theorize that they then took big sheets of this cardboard and used it to make packing cartons from. Would be a worthy reuse, and given the way Japan is limited in space for unglamorous things like landfills, I figure they were trying to reduce waste even back in the 70's.

 

[kray]

So just wanted to update. I had sent my 555A off to Leestereo for a full restore, and just got it back today. As I suspected and he verified as well, it has very little use on it for being 47yrs old.

First off Leestereo is top notch. One of the best experiences I've ever had having gear worked on. He did the full array up upgrades he posted in his 555A thread and man this sucker sounds so good. One of the biggest surprises is the phone section is now about 90% of my Lounge Audio LCR phono pre. It's super close, but the Lounge does outperform by just a hair. If I was using a cheaper phono pre I'd probably sell it and just use direct to the 555a.

So happy with this upgrade/restore.

 

[Mr. Nick]

It really takes certain kind of people to store a cardboard box in a way that it looks like almost mint after 50 years of time.

I've been reading threads like this about Sui three-digit series and how good sound they put out. As I am in the capacitor coupled -camp I couldn't walk out from an opportunity to get one of these into my collection as one came my way.

As soon as the Sui arrived to the doorstep I also had to create shopping list on Digikey to recap the unit. It's amazing how fast Digikey can deliver an order to Europe from the States. Just 3 days and I had the new parts with me.
Now the AU-555A is completely recapped, both rectifiers replaced and 2 watt resistors replaced the originals in the power supply. All pots deoxited as well.

It's my fourth day listening to this, new caps are still burning in. Sounds very nice indeed! RIAA sounded very sweet, one of the best I've heard.
At least this unit has some transformer hum, buzz, which is notable at very low volume at late evening.
Probably I have to live with it?
I have Sui 1000x and 5000 as well from the same perioid, which don't have so notable hum.

Here are few photos.



Speaker 'A' terminals had these plugs inserted in them.
I wonder what these are for, never seen these before?



So, one of these great units rescued again from becoming land fill too soon.

 

[ivandezande]

It really takes certain kind of people to store a cardboard box in a way that it looks like almost mint after 50 years of time.

I've been reading threads like this about Sui three-digit series and how good sound they put out. As I am in the capacitor coupled -camp I couldn't walk out from an opportunity to get one of these into my collection as one came my way.

As soon as the Sui arrived to the doorstep I also had to create shopping list on Digikey to recap the unit. It's amazing how fast Digikey can deliver an order to Europe from the States. Just 3 days and I had the new parts with me.
Now the AU-555A is completely recapped, both rectifiers replaced and 2 watt resistors replaced the originals in the power supply. All pots deoxited as well.

It's my fourth day listening to this, new caps are still burning in. Sounds very nice indeed! RIAA sounded very sweet, one of the best I've heard.
At least this unit has some transformer hum, buzz, which is notable at very low volume at late evening.
Probably I have to live with it?
I have Sui 1000x and 5000 as well from the same perioid, which don't have so notable hum.

Here are few photos.

View attachment 1444767 View attachment 1444768 View attachment 1444769 View attachment 1444770

Speaker 'A' terminals had these plugs inserted in them.
I wonder what these are for, never seen these before?

View attachment 1444771

So, one of these great units rescued again from becoming land fill too soon.

Looks good, I wouldn't worry about the transformer hum, my AU-666 has it too.
You left the 2SC871's in the eq and phono pres? Those gotta go.

 

[Mr. Nick]

Looks good, I wouldn't worry about the transformer hum, my AU-666 has it too.
You left the 2SC871's in the eq and phono pres? Those gotta go.

Thanks. You might be right about those old transistors.
I didn't touch them, since there's no actual problem with the sound itself.
Usually, if there's no real fault with the amplifier I have not touched on the transistors.

But I have a stash of KSC1845s just in case I change my mind.
Just understood these don't have as high hfe ratings as the originals tho.

 

[Leestereo]

...But I have a stash of KSC1845s just in case I change my mind.
Just understood these don't have as high hfe ratings as the originals tho.

KSC1845s with hFE ratings of ~400 are common and have been successfully used in 555A restorations by a number of AK members. Also, the 555A will greatly benefit from the installation of a Baxandall Diode and a Vbe Multiplier by-pass capacitor; details of these modifications can be found at this link .

 

[Mr. Nick]

Also, the 555A will greatly benefit from the installation of a Baxandall Diode and a Vbe Multiplier by-pass capacitor; details of these modifications can be found at this link .

Thanks for pointing out those mods. When I rotate amps again I could add those mods, they are not very difficult to do. I forgot to order new bias trimmers, which I also have in mind to replace. So little work still to be done. At first it seemed like there's a problem with the unit, because I wasn't able to adjust the bias. It was final step to be carried out. There were no readings at all. After scratching some head and reading few resistors around the bias trimmers I soaked both trimmers in deoxit spray and turned them side to side 10 times and now the bias is set. Good idea to replace those trimmers as well.

Your thread is really work of art. I just imagine how many hours it must have taken to write all that down photo-editing included. It's really easy to follow.

 

[slimecity]

So, one of these great units rescued again from becoming land fill too soon.

If you havent been able to do all of Lee's mods i thoroughly recommend that you do.

Its a night and day difference. I coudlnt handle listening to an original 555a again now that I have done them. I have been ruined.....

 

[kray]

Let me update you on the RIAA phono performance.

I've been using the Sui phono the last 2 weeks and decided to do new A/B testing with the Lounge. I'm not sure what opened up etc, but honestly the 555a phono is just as good or better than the Lounge now. I really couldn't believe it, but direct comparisons of the same vinyl back to back proved it for me.

Now the bonus! The 555a has TWO phono inputs.... so now I have a reason to get another turntable

 

[sinewaver]

I picked up a 555a a number of years ago, pitiful specimen of it's sort. Years of poor storage. Veneer bad, grunge on the face plate. Bought it anyway. I wanted a black Sansui. Took almost a month to clean it. Pots and switches all fouled. Big surprise was finding traces of the blue plastic wrap still on the trim. Seems like way more storage than use. The cabinet still needs veneer but it sounds incredible. I'm sure the modded units sound wonderful but given that mine takes over thirteen seconds for the power supply caps to bleed down at turn-off, I'm not inclined to go replacing any bits. I'm very happy with it as-is. It gets use in rotation and always puts a smile on my face. I can't find a reason to change anything. No hum, no pops, just sweet. Made me sell off a KA6000 I had, no comparison at all.