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View Full Version : Sansui valve phonostage CLONE


Wakefield Turntables
23-01-2018, 20:52
I noticed this.

https://www.ebay.co.uk/itm/1pcs-No-feedback-MM-MC-Phono-amplifier-bare-PCB-base-on-Sansui-high-level-MM/222613800758?hash=item33d4d10736:g:SqkAAOSw1EhZkmR c

Looks like it's based around 12AX7 valves. I seem to have a fetish for clones and valve phonostages.

I wonder if this could make a good project. :eek:
anubisgrau
24-01-2018, 07:22
I noticed this.

https://www.ebay.co.uk/itm/1pcs-No-feedback-MM-MC-Phono-amplifier-bare-PCB-base-on-Sansui-high-level-MM/222613800758?hash=item33d4d10736:g:SqkAAOSw1EhZkmR c

Looks like it's based around 12AX7 valves. I seem to have a fetish for clones and valve phonostages.

I wonder if this could make a good project. :eek:

Maybe, I would just love to see the Sansui phono first. Not that I know that much about Sansui history, but I'm pretty confident that from mid-70s on (when I started following them), they haven't had a separate RIAA from their integrateds/receivers.

There's a plenty of functional phono DIY projects around and I would go for those based around D3a, E810F or other tubes of a rather higher industrial grade than ECCxx which may cause a plenty of issues, especially in low signal positions, due to variations from reference quality. You have a nice Thorsten Loesch LCR RIAA schematics on the net, with 600 ohm LCR network. Things can hardly get better than that.

EDIT - I see the schematics on Ebay now. I don't get what six ECC83 are for in a phono stage?!
Firebottle
24-01-2018, 08:11
The ECC83's are being used in the SRPP configuration in an attempt to normalise the gain and Miller capacitance, with different valve characteristics and age.

I would guess that the noise performance would be poor on MC, with valve selection needed.
RothwellAudio
24-01-2018, 09:26
I would guess that the noise performance would be poor on MC, with valve selection needed.
Agreed.
Also, "no feedback" is rather misleading. There's feedback all over that circuit.
Firebottle
24-01-2018, 09:39
Yes, no 'overall' feedback is rather what I think is meant.
Wakefield Turntables
24-01-2018, 18:48
Will stick with the EAR clone.