Jump to content

Sansui AU-111, 907 NRA, Alpha 907 Review


Recommended Posts

49 minutes ago, Southie Adam said:

Does this have the Tamura transformer?

 

Good question... the X-1111 was manufactured with both the older type of transformer and the newer Tamura transformer. 

 

@Sansui77  shine a torch through the slots in the top cover and let us know! :)

 

EDIT: from what I can tell (and I still have some serial number searching to do!) it looks like the 88-89 build models are the conventional transformer, and the post-1990 models are the Tamura. This makes sense as the 907DR was released in 1990 and featured the Tamura transformer. It's also worth noting that both the 907DR and AU-X1111 were available in 100V JDM and 230V Euro versions which was a first for the top-line Alpha generation of amps.

 

I've also seen some serial numbers on the 1111 indicating they were manufactured in 1992 which is very interesting!

Edited by pete_mac
Link to comment
Share on other sites



On 21/06/2020 at 6:56 PM, Sansui77 said:

Would love to come up to a Sansui gtg and meet all you guys in person at some stage when this con19 is all done and dusted. 

 

So what list do we currently have between us all? It's a great list ?

 

 

AU-111

907 NRA 

907 Limited 

AU-1111 MOS Vintage

 

@Cafad @pete_mac 

B/C2302

907 DR

907 MR

907 XR

607 NRA II 

 

Did I miss a model?

 

Anyone with a AU-X1 or II?

 

 

 

There's a 907i and 907KX to add to that list - along with a 607MRX and AU-X711 (same amp stage as Cafad's 911DG but no digital stage).

 

What a bloody impressive list it is!

 

Dad also has the B/C2102 combo which pre-dates the alphas but basically the pre-power version of the AU-G99X amp and is x-balanced. 

 

 

Edited by pete_mac
  • Like 3
Link to comment
Share on other sites

2 hours ago, pete_mac said:

 

Good question... the X-1111 was manufactured with both the older type of transformer and the newer Tamura transformer. 

 

@Sansui77  shine a torch through the slots in the top cover and let us know! :)

 

EDIT: from what I can tell (and I still have some serial number searching to do!) it looks like the 88-89 build models are the conventional transformer, and the post-1990 models are the Tamura. This makes sense as the 907DR was released in 1990 and featured the Tamura transformer. It's also worth noting that both the 907DR and AU-X1111 were available in 100V JDM and 230V Euro versions which was a first for the top-line Alpha generation of amps.

 

I've also seen some serial numbers on the 1111 indicating they were manufactured in 1992 which is very interesting!

No, mine is not the Tamura version. I was actually looking for the Tamura version but by the time you pay the 37kg fee from Japan, it wasn't worth it. Franco Cozzo gave me a great deal on this one ?

IMG_20200622_191405.thumb.jpg.2c3259dbd71fac75bc34ddea0c877a52.jpg

 

The Tamura version 1111MV sells for a higher price in Japan because it's rare and it was a shorter production run with the new model / 907DR coming into release as well. I wouldn't think there would be much difference in the SQ department. Remember, the top B23XX power amps use the same conventional type transformers. 

 

Edited by Sansui77
  • Like 2
Link to comment
Share on other sites

Just now, Sansui77 said:

The Tamura version goes for much of a higher price in Japan because it's rare and it was a shorter production run with the new model / 907DR coming into release as well. I wouldn't think there would be much difference in the SQ department. Remember, the top B23XX power amps use the same conventional type transformers. 

 

 

Oh yes, I agree. Sansui have always used excellent transformers - Tamura or otherwise. It's a non-issue IMHO. 

  • Like 2
Link to comment
Share on other sites



12 minutes ago, Sansui77 said:

B23XX power amp

Screenshot_20200622-195236.thumb.png.4cb05ed022f0a8b230a20f30eede46ef.png

AU-1111MV

Screenshot_20200622-195344.thumb.png.37428124b70dc7fbd9b8a700bec5bce1.png

They look similar in their layout configuration don't they?

 

They do indeed!

 

The later power amps like the B-2103 and B-2105 are even closer!

 

 

AU-X1111MOS

 

AUx1111mos.jpg.9b191380964d5ecc69e649b9cce48472.jpg

 

 

AU-X1111MOS with Tamura:

 

537543683_aux1111mostamura.jpg.5f62f3aebdf5d2d0e150fe282f3cc4e0.jpg

 

 

B-2105:

 

b2105.png.a5e7b02ef07bf389cd0dfe1b5a7dba61.png

 

 

 

  • Like 1
  • Love 1
Link to comment
Share on other sites

That's unbelievable Pete...... There's 10 years between the two and they look 95% identical in their layouts. Obviously the newer B2105 had the newer design - tighter torrance components fitted but WOW. 

  • Like 1
Link to comment
Share on other sites

56 minutes ago, Sansui77 said:

That's unbelievable Pete...... There's 10 years between the two and they look 95% identical in their layouts. Obviously the newer B2105 had the newer design - tighter torrance components fitted but WOW. 

 

They are certainly close - the B2103 circuit appears to be an evolution of the X1111MOS. The B2103 is slightly simplified in some areas, with much greater use of the RIKEN resistors and the use of more U-Con black polypropylene caps and not so many of the copper foil styrene caps.

 

 

 

AU-X1111MOS:

 

 

x1111-3-l.thumb.jpg.a108ac2d061d40b5a4dec5538121f6e0.jpg

 

 

 

B-2103:

 

b2103mos-1b.thumb.jpg.cb55dc7f1a53fb79bc6ab34762a51878.jpg

  • Like 2
Link to comment
Share on other sites

24 minutes ago, pete_mac said:

 

They are certainly close - the B2103 circuit appears to be an evolution of the X1111MOS. The B2103 is slightly simplified in some areas, with much greater use of the RIKEN resistors and the use of more U-Con black polypropylene caps and not so many of the copper foil styrene caps.

 

 

 

AU-X1111MOS:

 

 

x1111-3-l.thumb.jpg.a108ac2d061d40b5a4dec5538121f6e0.jpg

 

 

 

B-2103:

 

b2103mos-1b.thumb.jpg.cb55dc7f1a53fb79bc6ab34762a51878.jpg

With upgraded circuit components, they look identical Pete. Why change something that works well.

Edited by Sansui77
Link to comment
Share on other sites



18 minutes ago, Sansui77 said:

With upgraded circuit components, they look identical Pete. Why change something that works well.


Very close, but not identical - they certainly changed the circuit over the years. Nothing too drastic though!
 

Much like the 907s, Sansui pursued a philosophy of evolution rather than revolution.  

  • Like 1
Link to comment
Share on other sites

  • Recently Browsing   0 members

    • No registered users viewing this page.




×
×
  • Create New...
To Top