Another AU-919
- Thread starter Hyperion
- Start date
-
- Tags
- au-919 reconditioning
Multimode
Active Member
Just a quick update, three months on...
The overhauled AU-919 is continuing to give me more pleasure than I can describe. There remains no doubt that John (Hyperion) brought it to a condition better than new. Not only is the sound quality improved, it's the first time in 37 years and two listening rooms that the tone and balance controls have been surplus to requirements. And his elimination of the unseen but deadly black flag capacitors and corrosive glue is a bonus!
The overhauled AU-919 is continuing to give me more pleasure than I can describe. There remains no doubt that John (Hyperion) brought it to a condition better than new. Not only is the sound quality improved, it's the first time in 37 years and two listening rooms that the tone and balance controls have been surplus to requirements. And his elimination of the unseen but deadly black flag capacitors and corrosive glue is a bonus!
Multimode
Active Member
Another quick update, six months from the previous one...
There’s still no doubt whatsoever that the AU-919 is performing significantly better than when new. As mentioned before, I always needed to deploy the tone controls prior to Hyperion’s restoration work but don’t need them at all now.
More importantly, the music now sounds exactly right, following some 36 years of ‘nearly right but...’. For instance, in the 1970s I trained (but never ‘graduated’) as a cornet player in a brass band, and in the 1980s I regularly sat in on a local big band’s practice sessions in which a friend played baritone saxophone, and for the first time since then I’m hearing via the AU-919 the true sound of brass instruments.
Thanks again, John!
There’s still no doubt whatsoever that the AU-919 is performing significantly better than when new. As mentioned before, I always needed to deploy the tone controls prior to Hyperion’s restoration work but don’t need them at all now.
More importantly, the music now sounds exactly right, following some 36 years of ‘nearly right but...’. For instance, in the 1970s I trained (but never ‘graduated’) as a cornet player in a brass band, and in the 1980s I regularly sat in on a local big band’s practice sessions in which a friend played baritone saxophone, and for the first time since then I’m hearing via the AU-919 the true sound of brass instruments.
Thanks again, John!
Thanks David,
I think it really means something about how good an amplifier is when a trained ear can speak so highly of it. It just bears out what is said about several amplifiers, but especially including the AU-919 - when it is described as "a piece of wire with gain". The combination of good design with modern components where it counts make the AU-919 stand out from the crowd, there is no doubt about that.
Last edited:
Another quick update, six months from the previous one...
There’s still no doubt whatsoever that the AU-919 is performing significantly better than when new. As mentioned before, I always needed to deploy the tone controls prior to Hyperion’s restoration work but don’t need them at all now.
More importantly, the music now sounds exactly right, following some 36 years of ‘nearly right but...’. For instance, in the 1970s I trained (but never ‘graduated’) as a cornet player in a brass band, and in the 1980s I regularly sat in on a local big band’s practice sessions in which a friend played baritone saxophone, and for the first time since then I’m hearing via the AU-919 the true sound of brass instruments.
Thanks again, John!
Great story, the fact that you've had your 919 that long and stuck with it says a lot- and yes, a proper restoration does make a difference.
I think you made the right choice in having it restored, especially by Hyperion who is well qualified. As a bonus, he's one of us -he appreciates the "special" amps in the Sansui line-up. I've never heard a 919 but I have no doubt that it is fantastic.
I think you're spot on about the way some of these high speed Sansui amps reproduce brass instruments. I'm not qualified like you are in this area but I have heard exactly what you are talking about. As a matter of fact, it's one of the things that struck me. I've never heard brass reproduced like that! I enjoyed it so much that it's led me to seek out and listen to new music. Love that brass when reproduced so realistically. Wow!
Just this past month I listened to two live bands, one in a very small club in New Orleans and the other in a larger venue (~ 2000 seats) in New York . Two totally different genres that were not (up until recently) in my wheelhouse but my Sansui took me there
. In the small New Orleans venue we were one row of tables back from the band which had a trombone, trumpet & saxophone, my wife and I looked at each other and smiled, The instruments sounded exactly like we hear them at home. Coincidentally, in the larger venue in NY I was also two rows back but the band was larger. They had 4 trombones (on my side of the stage ) along with several other brass instruments and it was great!Nothing like going out there and listening to live un-amplified instruments to keep our ears honest.
Keep enjoying that AU-919. I have no doubt that it is a very special amplifier.
Multimode
Active Member
Yes, an excellent post, Vintagear, and I love your username too!
I wouldn't say I'm particularly "qualified", since my live listening was many years ago and I'd had no actual concern about the 919's reproduction of brass instruments prior to the restoration . It was only afterwards that I realised that I hadn't been hearing quite the full 'rasp' of brass.
Conversely - and much more noticeably - very high treble often sounded harsh enough for me to use the tone control, and I normally left this switched in full-time. However the cut it gave didn't help much with the harshness and, as I write, I realise that it probably didn't help with true brass reproduction either!
I mentioned the harshness problem to Hyperion prior to the start of restoration and he said he'd look to see what could be done to overcome it. I'd always suspected the cause to be incompatibility somewhere along the line from source to speakers, but all is now fine so the culprit must have been the original build errors that he found and corrected.
It used to be a case of "I think I'll play a bit of music as it's been a long time...". That has now morphed into "I can't wait to put some music on...". My last listen was to Bill Frissell's album 'East/West' at rather high volume. That was late last night and I hated having to switch off 2/3ds of the way through as others were in bed - and I can't wait to continue with it ASAP!
I wouldn't say I'm particularly "qualified", since my live listening was many years ago and I'd had no actual concern about the 919's reproduction of brass instruments prior to the restoration . It was only afterwards that I realised that I hadn't been hearing quite the full 'rasp' of brass.
Conversely - and much more noticeably - very high treble often sounded harsh enough for me to use the tone control, and I normally left this switched in full-time. However the cut it gave didn't help much with the harshness and, as I write, I realise that it probably didn't help with true brass reproduction either!
I mentioned the harshness problem to Hyperion prior to the start of restoration and he said he'd look to see what could be done to overcome it. I'd always suspected the cause to be incompatibility somewhere along the line from source to speakers, but all is now fine so the culprit must have been the original build errors that he found and corrected.
It used to be a case of "I think I'll play a bit of music as it's been a long time...". That has now morphed into "I can't wait to put some music on...". My last listen was to Bill Frissell's album 'East/West' at rather high volume. That was late last night and I hated having to switch off 2/3ds of the way through as others were in bed - and I can't wait to continue with it ASAP!
Last edited:
Multimode
Active Member
Incidentally, there's a bonus with my AU-919 underperforming for all those years. If it had worked as it should I'd have used it a great deal more, resulting in a good chance of black flag failure killing the output transistors. I was unaware of this risk until joining AK a little over a year ago so will be forever grateful. Thank you! 
_mano
Well-Known Member
Hi David,
Very similar story, bought the AU-919, TU719, SR525 new in 78ish at Edgware Rd, used/abused till the the late 90's. Little annoying issues, so sidelined all for the inyourear_mp3 and in 2013 it was all heading to the local dump yard. Just by chance checked eb&*, and was blown away by the demand and price. So, scanned and came across the knowledge mine of AK, with help of John, Kale, and many others, restored 919,TU719,111,SR525,CA3000,SR929 and rest his music as they say. Unbelievable how my ears got used to canned music in my ear...
Another regret avoided.......
Mano
Very similar story, bought the AU-919, TU719, SR525 new in 78ish at Edgware Rd, used/abused till the the late 90's. Little annoying issues, so sidelined all for the inyourear_mp3 and in 2013 it was all heading to the local dump yard. Just by chance checked eb&*, and was blown away by the demand and price. So, scanned and came across the knowledge mine of AK, with help of John, Kale, and many others, restored 919,TU719,111,SR525,CA3000,SR929 and rest his music as they say. Unbelievable how my ears got used to canned music in my ear...
Another regret avoided.......
Mano
Just the thought of a 919 going to the local dump sends shivers down my spine!!!
_mano
Well-Known Member
Yeahh, we all go through this spineless phase, as we did with Tube Amps for Trannies, and dumping all the Vinyls for CD's... (near miss here)
That's when you know you've struck sonic gold!
Hello guys!
Three days ago I entered in possession of an Au 919 and unfortunately for me, it looks painful inside. I'll put some pictures for the example.
The major problem with it is that out of the eight final transistors there is only one original one. The rest is a soup, a blend of 4 Thoshiba with 1 Sanken and 3 Motorola + 1 Sansui.
I read this forum about the restorations of this wonderful device, which I wanted very much, so I will appeal to yours goodness to help me with some ideas on what to do next. I tell you from the beginning that I do not know nothing about of electronics and I will appeal to one electronist who is a few hundred miles away from me. I would trust with one of those who posted here the Au 919 restoration but the distance is very big because I live in Romania.
I have been looking for some replacement days for the original transistors and from what I read here on the forum I understood that they successfully used the 2SA2121 / 2SC5949 pair to which I would have access but do not know if they are counterfeit by the Chinese. I searched the site: http://www.sansui-parts-shop.com where I found only 2SC2607, 2SA1116 have no stock, the latter being those recommended by the manufacturer.
Another problem I have found is that when applying tuna corrections, they feel hardly at all. So there's should be work there.
He is in working order and this looks very good. I really want to restore it and enjoy the sound of Sansui. Now with the transistor mix does not differ much from the old HK680 amplifier.
The speakers I'm going to pair with are HPM 110, which will also need to be restored. the parts in the filters are original, but I noticed that colloid was passed from the capacitors.
I apologize for English, I asked for Google translation help
Best regards!
Three days ago I entered in possession of an Au 919 and unfortunately for me, it looks painful inside. I'll put some pictures for the example.
The major problem with it is that out of the eight final transistors there is only one original one. The rest is a soup, a blend of 4 Thoshiba with 1 Sanken and 3 Motorola + 1 Sansui.
I read this forum about the restorations of this wonderful device, which I wanted very much, so I will appeal to yours goodness to help me with some ideas on what to do next. I tell you from the beginning that I do not know nothing about of electronics and I will appeal to one electronist who is a few hundred miles away from me. I would trust with one of those who posted here the Au 919 restoration but the distance is very big because I live in Romania.
I have been looking for some replacement days for the original transistors and from what I read here on the forum I understood that they successfully used the 2SA2121 / 2SC5949 pair to which I would have access but do not know if they are counterfeit by the Chinese. I searched the site: http://www.sansui-parts-shop.com where I found only 2SC2607, 2SA1116 have no stock, the latter being those recommended by the manufacturer.
Another problem I have found is that when applying tuna corrections, they feel hardly at all. So there's should be work there.
He is in working order and this looks very good. I really want to restore it and enjoy the sound of Sansui. Now with the transistor mix does not differ much from the old HK680 amplifier.
The speakers I'm going to pair with are HPM 110, which will also need to be restored. the parts in the filters are original, but I noticed that colloid was passed from the capacitors.
I apologize for English, I asked for Google translation help
Best regards!
Multimode
Active Member
An abbreviated quote follows, taken from an old post:
John's increase to the MC input impedance overcame the mismatch problem, with listening tests revealing little difference between MC direct and step-up transformer into MM. The modification will also facilitate a wider choice of MC cartridges should a future need arise.
The question is, could a little more work by Sansui have rendered the MC input more cartridge-tolerant? This is suggested to me by the article from a former Sansui engineer, referenced elsewhere on AK: https://ishinolab.net/modules/doc_serial/audio_history_japan/serial001_010.html. I read it as saying that the MC head amp in the AU-D907/AU-919 was imperfect. If it says what I think it says, I would agree!
The applicable passage follows:
Application to MC cartridges
The evaluation of MC cartridges has been high, perhaps because of the influence of opinion leader Takashiro's article at the time. The trend of the wind that it was not a cartridge came out if it was not MC. Well, there was also an MC transformer how to handle with the pre-main amplifier, but I avoided the fact that installing it in the amplifier would draw hum noise, and I started to incorporate an MC head amplifier. The AU-D907 was also pressed to respond, and the FET was para-connected to create and incorporate a head amplifier. I didn't care much about the sound quality of this head amplifier. It didn't have a great quality sound quality, and there wasn't much time to study. Even if I visited the critic's house, it was normal to get output from a high-end MC transformer and conduct a hearing test. In short, the head amplifier of the pre-main amplifier was an addition.
Do I understand correctly?
John's increase to the MC input impedance overcame the mismatch problem, with listening tests revealing little difference between MC direct and step-up transformer into MM. The modification will also facilitate a wider choice of MC cartridges should a future need arise.
The question is, could a little more work by Sansui have rendered the MC input more cartridge-tolerant? This is suggested to me by the article from a former Sansui engineer, referenced elsewhere on AK: https://ishinolab.net/modules/doc_serial/audio_history_japan/serial001_010.html. I read it as saying that the MC head amp in the AU-D907/AU-919 was imperfect. If it says what I think it says, I would agree!
The applicable passage follows:
Application to MC cartridges
The evaluation of MC cartridges has been high, perhaps because of the influence of opinion leader Takashiro's article at the time. The trend of the wind that it was not a cartridge came out if it was not MC. Well, there was also an MC transformer how to handle with the pre-main amplifier, but I avoided the fact that installing it in the amplifier would draw hum noise, and I started to incorporate an MC head amplifier. The AU-D907 was also pressed to respond, and the FET was para-connected to create and incorporate a head amplifier. I didn't care much about the sound quality of this head amplifier. It didn't have a great quality sound quality, and there wasn't much time to study. Even if I visited the critic's house, it was normal to get output from a high-end MC transformer and conduct a hearing test. In short, the head amplifier of the pre-main amplifier was an addition.
Do I understand correctly?
