Tube AC filaments on PCB

[beatnik]

I'm designing a PCB for a tube compressor , the tube filament supply is 6,3AC 1.6A
Initially I thought to make the supply DC , but the power transformer becomes too big.

I have seen many projects where the filaments are wired in twisted pairs off the board, which certainly is a feasible solution, but I have also seen some commercial units that seemingly run the heaters AC on the PCB.

Perhaps if the AC lines are kept on the edge of the board and away from grid circuits it's possible to avoid noise ?
Also heater elevation could help ?

I might just try a prototype pcb but I was wondering if anybody has experience with this

 

[trobbins]

Heater elevation does not suppress the same mechanism of hum transfer as close proximity of heater wires to the input stage input grid (or other sensitive circuit nodes). Close proximity of heater wires to circuitry is typically suppressed with a tuned humdinger, so I'd suggest adding say a 0.6W 200R pot as the humdinger, and trying to improve separation distance and gnd guarding for input circuitry, or subsequent low level circuitry.