New Phono Stage

[Spur07]

Hi all

I took a punt on this MJS phono stage the other day on fleabay. This was the blurb:

This unusual phono preamp was possibly a bespoke design for a recording or broadcast studio. It was originally with a Technics SP10 turntable.

The preamp features it's own regulated power supply with toroidal transformer, low noise op amps (TDA 1034 and LF356), trimmer pots and capacitors in the equalisation stage and balanced outputs via XLR chassis plugs (pin 1 common). The outputs are buffered by no less than eight (8) unity gain 741 type op amps per channel and the output wiring has ferrite beads to prevent RF pick up. All of this is contained in an earthed metal case.

It's got 4 adjustment holes - 2 on the side, I think for overall gain, and 2 on the top apparently to "...adjust the high frequency roll off i.e. the RIAA 75us transition"

I have no experience of phono stages. If any (regular) AOS'ers want to borrow and try/compare you're more than welcome. Its very detailed and fast compared to my amp phono without bloom, maybe a bit overwhelming at the top end on some LP's. Should I p*ss about with those adjusters, or would it be better to find someone with some measuring equipment? :)

http://i601.photobucket.com/albums/tt94/spur07/MJS/2.jpg

http://i601.photobucket.com/albums/tt94/spur07/MJS/3.jpg

http://i601.photobucket.com/albums/tt94/spur07/MJS/4.jpg

http://i601.photobucket.com/albums/tt94/spur07/MJS/5.jpg

http://i601.photobucket.com/albums/tt94/spur07/MJS/1.jpg

P

[sq225917]

you might be lucky here. I have a sneaking suspicion the guy who designed this has just posted on the WAm in the past week. Stick a post up there and see if he answers, I'm sure i haven't imagined this.

[Spur07]

Will do Simon. Thanks for the tip off.

P