Valve Itch phono

diyAudio Chief Moderator
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-Yes x10
-It would take you rewire the valve bases. Pins are not the same.
 

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diyAudio Chief Moderator
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One is a 6.3V valve the other one is a 12.6V valve as you see.
So to heat the 6N2PEV you give 6.3V to pins 4,5 and pin 9 is a shield that goes to ground.
When to heat the 12AX7 with 6.3V you short 4,5 and you put that voltage between them and pin 9.
There is no shield and no low grid leakage spec provision. So you could possibly need the diode trick if you will try with 12AX7/ECC83.
 
diyAudio Chief Moderator
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What's the MM voltage input 3mV? Can increase 5dBs of gain, so I will use Partridge 977 x6?

There is 43dB of gain in the main circuit that can be used with HMC even. As it had been done at least by one user with success.
Combining the 977 it will go near 59dB. Are you sure its not enough for the cart you got in mind? Because to get more gain means different second stage tube modification.
 
diyAudio Chief Moderator
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x10 again, it was a Dynavector DV/6Z step-up. That makes 63dB in combination with the Itch.
I don't remember the 977 pins. But you can use your generator at 10mV/1kHZ and see on your scope which way it goes X6.
Should give about 170mV pk-pk on screen when used the right way.
(In which way it steps up in general is enough to find. Because if your generator impedance is high it may alter the multiplication figure).