Hum

tsingle999 · 2156

0 Members and 1 Guest are viewing this topic.

Offline tsingle999

  • Sr. Member
  • ****
    • Posts: 275
  • We are all here because we are not all there.
on: May 13, 2013, 07:05:35 AM
I have a hum that seems to follow the 45 tube. Its louder than normal hum. Is it a bad tube?

SGS iTransporter with Qobuz & Roon to Optical Rendu to BH DAC (Battery) / Wavelegth Cosecant to BeePre to 300b(ehemoths) to Jagers.
Bottlehead Stat headphone amp with Wavelength Brick DAC


Offline galyons

  • Sr. Member
  • ****
    • Posts: 626
  • Geary Lyons
Reply #1 on: May 13, 2013, 08:09:09 AM
...hum that seems to follow the 45 tube.

Sadly, most likely it is the tube!
Cheers,
Geary

VPI TNT IV/JMW 3D 12+Benz LP-S>  Eros + Auralic Aries + ANK Dac 4.1 >Eros TH+ Otari MX5050 IIIB2 > BeePre >Paramount 300B 7N7 > EV Sentry IV-A

Thorens TD124/Ortofon RMG-212/SPU >Seduction > Smash^Up> Paramour 45 MQ >K12's


Offline Paul Joppa

  • Global Moderator
  • Hero Member
  • *****
    • Posts: 5834
Reply #2 on: May 13, 2013, 09:38:47 AM
The hum pot exists because tubes vary from one to another. But if you cannot get rid of the hum with the hum pot, then it's most likely the tube.

Paul Joppa


Offline tsingle999

  • Sr. Member
  • ****
    • Posts: 275
  • We are all here because we are not all there.
Reply #3 on: May 13, 2013, 10:14:07 AM
Ouch! The hum pot doesn't affect it. Ok thanks guys!
Its a Vaic vv45. Theres no issues using it with the sr45?
Filament voltage 2.5, filament current 7.35 amps, grid voltage 42
Ug and gm tested at ia 50 ma and ua 280 volts..
« Last Edit: May 13, 2013, 10:22:00 AM by tsingle999 »

SGS iTransporter with Qobuz & Roon to Optical Rendu to BH DAC (Battery) / Wavelegth Cosecant to BeePre to 300b(ehemoths) to Jagers.
Bottlehead Stat headphone amp with Wavelength Brick DAC


Offline Paul Joppa

  • Global Moderator
  • Hero Member
  • *****
    • Posts: 5834
Reply #4 on: May 13, 2013, 11:05:07 AM
Hope that 7.35 amps is a typo! Should not be any issues, except to check that the power line voltage is close to 120v.

Paul Joppa