Welcome To the Hoffman Amplifiers Forum

September 06, 2025, 04:51:49 pm
guest image
Welcome, Guest. Please login or register.
-User Name
-Password



Hoffman Amps Forum image Author Topic: Power Transformer Q  (Read 2515 times)

0 Members and 1 Guest are viewing this topic.

Offline johnheath

  • Level 1
  • *
  • Posts: 11
Hoffman Amps Forum image
Power Transformer Q
« on: June 26, 2011, 02:06:59 pm »
Hello

I am about to design an amp and I just have a few questions concerning the capacity of the power transformer.

I will build a "Tweed Super" but beefed up with a OT just like in a Super Reverb Blackface (125A9A) or (125A13A).

Now: The traditional TAD/MOJO 125P5DX or the Hammond 290DEX both matching 230mA but since I am only using two preamp tubes two 6L6 and a GZ34 rect. tube my question is if I can get a "smaller" PT that let's say deliver 173mA like the Hammond 376X... OR?

Am I looking at completely wrong facts here?

One of the benefits with the Hammond "Classic" 300-series is that they are top-mounted and requires no big holes to be mounted on the chassis... and this would ease my thoughts on building a really small but still powerful amp with real PtP.

Regards

/John

Offline eleventeen

  • Level 4
  • *****
  • Posts: 2229
Hoffman Amps Forum image
Re: Power Transformer Q
« Reply #1 on: June 26, 2011, 04:42:29 pm »
The preamp tubes use very little current...2-3 ma, usually. So they make very little difference in the overall scheme of things. Sounds to me like your proposed PT can easily handle the job.

Offline phsyconoodler

  • SMG
  • Level 4
  • *****
  • Posts: 4679
  • honey badger don't give a ****
Hoffman Amps Forum image
Re: Power Transformer Q
« Reply #2 on: June 30, 2011, 06:37:51 pm »
Are you in Europe? If not,the 272HX will do the job.The 372 version has 230v taps and a bias tap that the 2&2 does not have.
Honey badger don't give a ****

 


Choose a link from the
Hoffman Amplifiers parts catalog
Mobile Device
Catalog Link
Yard Sale
Discontinued
Misc. Hardware
What's New Board Building
 Parts
Amp trim
Handles
Lamps
Diodes
Hoffman Turret
 Boards
Channel
Switching
Resistors Fender Eyelet
 Boards
Screws/Nuts
Washers
Jacks/Plugs
Connectors
Misc Eyelet
Boards
Tools
Capacitors Custom Boards
Tubes
Valves
Pots
Knobs
Fuses/Cords Chassis
Tube
Sockets
Switches Wire
Cable


Handy Links
Tube Amp Library
Tube Amp
Schematics library
Design a custom Eyelet or
Turret Board
DIY Layout Creator
File analyzer program
DIY Layout Creator
File library
Transformer Wiring
Diagrams
Hoffmanamps
Facebook page
Hoffman Amplifiers
Discount Program