Differential AKSA GK1R pre-amp

[Builder Brad]

Hi Hugh,

what are your thoughts on this?

Could it work?

would chips such as the DRV134 and DRV135 be useful in converting SE inputs and providing SE outputs

could a standard GK1R be upgraded with an extra main board, plus the extra input and output stages.

Brad

[AKSA]

Brad,

The input on the GK1R is a diff pair, and could relatively easily be adapted for balanced inputs. It would involve a fair amount of R&D, however, which I'm reluctant to do because the preamp works so well as it is.

There are chips which will convert SE input to balanced, but the simplest add on is simply a Jensen or Sowter balanced line transformer. Hundreds are used in the signal chain in recording industry, so we know they work well.

Balanced lines are primarily used where runs are long and interference is strong - in sound reinforcement and recording applications where phase controlled lighting often creates major RFI. I do NOT recommend balanced lines for domestic high fidelity equipment.

The output stage of the GK1 would need radical restructing to give balanced out, however. That's not so simple, since the tube circuitry is all single ended.

Cheers,

Hugh