MPP

Urschrei

Hello Joachim,

I would like to congratulate you on the (IMHO) Best-Of-Show performance in Krefeld. I thouroughly enjoyed your Phänomen speaker and the Urschrei phono-amplifier!

Very nice to have met Martina Schoener and Stig Bjorge too, with indeed a STUNNING turntable combination: Transcriptor Reference / Lyra Atlas in a modified Origin Live arm. In combination with the workhorse speakers Martina uses for her product development unbeatable! (I didn't expect to ever write that, it's that good...:eek:)

By far the most enjoyable, natural and realistic sounding setup I have ever heard at an audioshow! My English fails me to express myself better...

Now I really want to build the High-Z FPS... :eek:
 
This a " good enough " circuit to test it. A single 2SC6000 is only 0.5dB worse then a differential triple.
 

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I called RS Europe, no 2SC6000(yet).
Long time ago i build the " good enough " circuit when i worked with Mr. Nordholt. Later he developed a special chip with a very big transistor with low Rb for Ortofon. The project was cancelled later. Found some BFW16A's in my drawer....
 
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This is all i have :
http://pia-hifi.de/wp-content/uploads/c-37_g.pdf
They even do a differential input that has a 6dB noise disadvantage over parallel symmetric.
This new input transistors must be very good because this phono stage is even 1dB more quiet then the last one and that was very quiet.

A little while ago I created an LTSpice mockup of the Accuphase C-37 MC stage based on the schematics in their brochure, but with different transistors as I didn't have suitable models. Their input stage looks deceptively simple so I thought I might give it a try. There is certainly room for improvement but unfortunately I have little to no time for audio right now to pursue this any further:
 

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Martin , I made some modifications at your schematics, and use the FZT849 because it will be more similar to the 2sc6000.

The circuit needs a DC servo or a capacitor at the output. And the resistor r106 should be current source. It need more improvement.
 

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