ecc82 5687 preamp! audionote

[tubo]

Hi all,

can I sub 6sn7 in place of ecc82 in this schematic? i have this as outputstage in my dac and it sounds very good, but i have plenty of 6sn7's id like to use. do i need to change the plate and kathode resistors of the ecc82s to accommodate the 6sn7's? the b+ voltage is 260v

thanks fellas

 

[azazello]

1. You can change the socket.
2. I plate about 6 ma. Rplate about 20 kohm, Rk about 500 ohm.

 

[tubo]

Thanks for your input. ill try it when i get some parts.

 

[Palustris]

Your schematic doesn't include any voltages, so it is hard to give an exact answer, but I would go with the same value resistors as drawn and shoot for a voltage on the 6SN7 plate of about 150V with a current of 6mA. You will need a supply of about 385V to achieve that operating point and you may need to increase or decrease the cathode resistor to dial in the voltage and current through the tube. Reducing the value of Rp will increase harmonic distortion.

 

[tubo]

Your schematic doesn't include any voltages, so it is hard to give an exact answer, but I would go with the same value resistors as drawn and shoot for a voltage on the 6SN7 plate of about 150V with a current of 6mA. You will need a supply of about 385V to achieve that operating point and you may need to increase or decrease the cathode resistor to dial in the voltage and current through the tube. Reducing the value of Rp will increase harmonic distortion.

hello,

B+ is 260v and is common to both stages!

 

[azazello]

To save the same Rp, You can use another OT with more U. 265V Doesn,t enought for pretube.

 

[tubo]

Thanks for all your inputs fellas, ill leave it as is. It's very good sounding afterall.

 

[azazello]

Sorry for my mistake, I mean Power transformer. with U 260v.