Trying to find............

[SuppersReady]

......... a balanced/differential input and output tube RIAA pre-preamp.

I'm sure I've seen one on this forum, and I've done several searches but can't find it again. Also searched the web without success. It may have been based on the EF86 tube.

Does anyone have the schematic out there?

Cheers

Paul

[fdegrove]

Hi Paul,

You mean a balanced phono preamp capable of taking in MC cartridges?

Have you checked out Allen Wright's design:

VACUUM STATE ELECTRONICS

Cheers,

[Brett]

Originally posted by fdegrove
Hi Paul,

You mean a balanced phono preamp capable of taking in MC cartridges?

Have you checked out Allen Wright's design:

VACUUM STATE ELECTRONICS

Cheers,

I speak from experience here. Allen's designs are exceptional. I use the RTP3C phono stage, currently with a differential version of the FVP5A (all tube) linestage (as well as my radically modified version of it).

The EF86 will be too noisy for MC use.

[7N7]

There is a rather elegant balanced RIAA circuit with full technical arguments in the second edition of "Valve Amplifiers" by Morgan Jones.

One chap on the AA claims to have built one and is very pleased with it.

7N7

[SuppersReady]

Thanks everyone,

Allen Wright certainly looks 'the business.' It is just the phono section that I wish to reproduc, so I'm presuming from the schematic that all I need for connction to my solid-state preamp is the section to the left of the dotted line. It looks simple enough to use PTP, and I'm presuming the valves should be too hard to get hold of in the UK.

Thanks again

Paul