Valve Itch phono

[Salas]

Try with R9 & R11 = 430R maybe

 

[merlin el mago]

Thank you Salas, wich resistor have I to measure for 9mA?

 

[merlin el mago]

Find it across R10.

 

[Salas]

Around 6mA it was on the Rev 1.2 prototype for 6SN7

 

[merlin el mago]

Thanks Salas.

 

[merlin el mago]

Salas if the heater regulators are in the same box with valve Itch are necessary the 3.300uF near the heaters?

 

[Salas]

No but do use something smaller across them like 100uF

 

[merlin el mago]

Solder direct at heater pins or heaters output?

 

[Salas]

The nearer to heater pins the better. Use 105C capacitors if its a hot spot.

 

[merlin el mago]

OK thank you.

 

[merlin el mago]

Can I ask what's the purpouse of this cap?

 

[Salas]

Decoupling / local energy reservoir

 

[merlin el mago]

Thanks again Salas.

 

[merlin el mago]

One capacitor each heater total 4 capacitors?

 

[Salas]

Yes, that will be best distribution of them

 

[merlin el mago]

 

[Bigun]

The sound is great. Lush but has it all. Best valve phono we ever had bar none. And we had tested about 7 DIY ones.:cool

Hi, any chance you or somebody has compared this with the Shindo Claret i.e. Thorsten's clone thereof, which uses an active topology ?

 

[Salas]

You mean an active RIAA? No, it was a Thorsten one with a passive and grid leak bias in the second stage if I remember well and a Steve Bench cascode one that I could listen to at that time. Wow 7 years gone from that first post... time's flying.

 

[Bigun]

Yes, the Claret was active if I remember and Thorsten had cloned it.

Doctorjohn Cheaptubeaudio: Audio Reviews and More: Review: SHINDO Claret preamplifier

 

[merlin el mago]

Salas channel right have more gain than channel left, attached scope shot 1kHz 10V/cm 1ms