Ultimate MC RIAA phono pre for "Blue Oasis" (Win Research Group) schematic?

[tiefbassuebertr]

For the cartridge "Blue Oasis" there are a special made MC pre amplifier from the brand
Sao Zaw Win (Win Research Group, Inc.)
formerly: Win Labs
7320 Hollister Avenue, Goleta, CA93117
Voice: (805) 968-5213. Fax: (805) 685-2781
information from 14 PDF- URL
http://www.theaudiocritic.com/back_i...ritic_17_r.pdf

For this device I need schematic and the IC "SL459" (SL 459) itself.

This IC is in use by the input stage (brand: Plessey). Datasheet unfortunately not online, but I have a original databook. Below you see a clone of the internal circuit (pdf schematic)

Perhaps one of the members know more about the currently brand name, additional about a delivery source for the "hard to find" part "SL-459".

Please note, only the outline of the SL459 is like a OP AMP (i. e. DIP-8) but not the internal topology.

A modification to the "easy to find" AD797 delivers not the sweet sonic performance than the SL-459.

Thank you for your advices.

[tiefbassuebertr]

Are there realy no informations ??

[tiefbassuebertr]

schematics still wanted

[Scott594]

Plessey was sold to Mitel in 1998. Here are possible sources for the SL-459.

Linecard

http://www.class-ic.eu/Files/Linecard.pdf

wizard-final

[kugel-balu]

Hi folks,

I had one for repair, and had to deal with the input chip.
It is NOT an SL459, as stated, but an SL561C, also from
Plessey. Similar function, but rather different pinning.

If anybody opts for a repair or improvement, good points
to observe are the following:

- the other chip on the tiny IC board is an NE5532N, which should
be replaced by the lower noise version, or (perhaps) by the
more recent improved versions from National
- the power supply is built with 78L15 / 79L15, with very little
filtering -- which limits the result quite a bit
- the capacitors in the RIAA network were standard
MKT types (at least in my copy), with rather high tolerance
(I checked them -- some 10 % difference left to right),
perhaps better replaced by 1 nF and 3.3 nF styroflex

So, some room for improvement here really , but beware
that unmounting and re-mounting the Pre needs some experience ...

Hope that helps.

[tiefbassuebertr]

Obviously your "McG-10" is an additional model from that brand, that I don't know this version. The version asked here for schematic is without type number and without model number (special made for the cartridge "Blue Oasis") and equipped with follow integrated circuits:
1) SL-459 (actually unknown because scratching out/polish off the type number, but pinning according the SL459)
2) NE5532
3) SG1468/1568 (dual tracking voltage regulator from Silicon General - see attached datasheet)

Genuine schematic diagram still wanted.