Home Tube DIY Asylum

Do It Yourself (DIY) paradise for tube and SET project builders.

RE: 5R4GY and filter cap values

A capacitor input filter ( first element after the rectifier tube ) is the worst possible design to have. The bigger the cap in uF value, the worst - off is the design.

The best practice is to always have a choke, of some kind, with adequate current rating, and lowest possible DCR and mass, as the first element the tube rectifier sees.

Chokes in tube amps, as for example, a 2A3 amp, need to all be 20 Ohms or less in DCR, and there is an advantage to getting down to ten Ohms or less. A double L/C section B+ filter is tops, as in L1/C1/L2/C2 to the Finals.

If employing high drop rectifiers, like a 5R4 or a whimpy 5Y3, you should avoid using larger uF C1 input cap values, its NG, design - wise, on a long-term reliability basis.

Jeff Medwin

This post is made possible by the generous support of people like you and our sponsors:
  Michael Percy Audio  

Follow Ups Full Thread
Follow Ups
  • RE: 5R4GY and filter cap values - drlowmu 08:43:47 03/21/17 (0)


Post a Message!

Forgot Password?
Moniker (Username):
Password (Optional):
  Remember my Moniker & Password  (What's this?)    Eat Me
E-Mail (Optional):
Message:   (Posts are subject to Content Rules)
Optional Link URL:
Optional Link Title:
Optional Image URL:
Upload Image:
E-mail Replies:  Automagically notify you when someone responds.