Went back to the sovtek 5y3 included by Dennis and the same hum. Unlike yesterday it doesnt seem that warmup has influenced the hum at all...maybe i was just listening to louder music yesterday that didnt have as much space between notes like I am today.
I do have the preamp plugged into a humx and the spectral analyzer on my phone shows a peak at/near 60Hz.
Was using some old RCA 6SN7s but then swapped in some old kenrads I had but worried one might have blown when it started to heat up
. Really bad hum like what I had with some electroharmonix a while ago. Think I see a crack near the base. Switched back to the GE's Dennis shipped with it and the buzz is still present.
Is there anything I should check internally before I reach out to Dennis besides an obvious loose connection?