6SN7 6N8S preamp suggestions

[merlin el mago]

6SN7 6N8S schematic preamp suggestions







I'm looking for high gain, high input impedance, low output impedance, low noise design with only 2 tubes so one per channel.

Ideas and suggestions will welcome.

[denny9167]

Originally Posted by merlin el mago

6SN7 6N8S schematic preamp suggestions







I'm looking for high gain, high input impedance, low output impedance, low noise design with only 2 tubes so one per channel.

Ideas and suggestions will welcome.

I've had good experiences with the SRPP,I haven't tried the other configurations. Just be sure to elevate your heaters. Thanks

Denny

[merlin el mago]

Thanks Denny, could you post your schematic used and let me know: gain, input/output impedance, etc?

[denny9167]

Originally Posted by merlin el mago

Thanks Denny, could you post your schematic used and let me know: gain, input/output impedance, etc?

Sure, I have the pic attached. Since the 12AU7 and 6SN7 are so close I made the substitution. The sound is really quite nice. Since the 6SN7 is an 8-pin octal you will have to change pin-out arrangment. I don't remember the gain, but it should be sufficent for what your looking for.

BTW, this schematic is designed to give you elevation on those heaters! Thanks

[merlin el mago]

Looks nice and very easy to do, surely I will try, thank you.

[tinitus]

been thinking if srpp would be good or maybe even ideal to drive a low impedance trafo output
which could be balanced 600/600 ohm

[merlin el mago]

I don't want to use output transformer.

[ruffrecords]

Use a mu follower. More gain, much less distortion than and SRPP and still the low output Z. Run the 6SN7 at around 5mA.

Cheers

Ian

[Davec113]

Originally Posted by ruffrecords

Use a mu follower. More gain, much less distortion than and SRPP and still the low output Z. Run the 6SN7 at around 5mA.

Cheers

Ian

I would agree, I had a mu follower pre using 6DJ8s and it had 28 dB gain very little distortion.

[vconsumer]

Originally Posted by ruffrecords

Use a mu follower. More gain, much less distortion than and SRPP and still the low output Z. Run the 6SN7 at around 5mA.

Cheers

Ian

Put a CCS on the plate of the voltage amplifier, bias it with LEDs, direct couple the two halves, and a put CCS on the mu follower. You will have a nice preamp.