Fender 6G15 Reverb unit, why use a 6K6 (6V6) instead of the usual 12AT7 ?

[Gingertube]

Small Amps too - particularly HiFi Amps, they are just one of those tubes which appeal.
Plenty of power for reverb drive, not dissing the 6BM8, I just prefer the 6DX8/ECL84
Cheers,
Ian

[Iplayloud]

Here's a clip of the finished product, enjoy

YouTube - Spring Reverb Test