Welcome To the Hoffman Amplifiers Forum

September 07, 2025, 10:35:13 pm
guest image
Welcome, Guest. Please login or register.
-User Name
-Password



Hoffman Amps Forum image Author Topic: Vox AC 30C2 Power tubes and diodes  (Read 2180 times)

0 Members and 1 Guest are viewing this topic.

Offline TerryD

  • Level 2
  • **
  • Posts: 304
Hoffman Amps Forum image
Vox AC 30C2 Power tubes and diodes
« on: July 08, 2014, 07:32:32 am »
First Thanks for all the help I get here.
Just picked up a "like new" Vox AC30C2 from a pawn shop for $500, with a cover and roller palatte.  With the MDF this thing brings about a "near death" experience each and every time you lift it. Sounds great though.
Do the El 84s need to be matched in a Vox Ac 30?   I'm thinking not.
It has a solid state rectifier.  I really like putting FREDS in these type of amps as to my ears they are more musical.  I don't suppose anybody here could give me the diode numbers for the rectifier off the schematic (which not one person seems to be able to find on the net).  Even if I had one, it would be good if I knew the board numbers.  Any easy place to get FREDS?
Also some people change the treble bypass cap on these.  What would that board number be?
 What are good tubes for these?
Thanks again
Terry
« Last Edit: July 08, 2014, 09:40:35 am by TerryD »

Offline Willabe

  • Global Moderator
  • Level 5
  • ******
  • Posts: 10524
Hoffman Amps Forum image
Re: Vox AC 30C2 Power tubes and diodes
« Reply #1 on: July 08, 2014, 08:16:45 am »
Hi Terry,

It would help if you would post a schemo of this amp.



                      Brad       :icon_biggrin:

Offline kagliostro

  • Level 5
  • *******
  • Posts: 7739
Hoffman Amps Forum image
Re: Vox AC 30C2 Power tubes and diodes
« Reply #2 on: July 08, 2014, 10:23:17 am »
Give a look to the library of schematics here in the forum

not now, but within today more late or tomorrow  :angel


K
The world is a nice place if there is health and there are friends

Offline sluckey

  • Level 5
  • *******
  • Posts: 5075
    • Sluckey Amps
Hoffman Amps Forum image
Re: Vox AC 30C2 Power tubes and diodes
« Reply #3 on: July 08, 2014, 05:00:47 pm »
Matched tubes are always desirable, but not an absolute necessity.

D7, D8, D9, and D10 are the four diodes you're interested in. They are 1N4007. AES has some freds.

Treble bypass cap??? Are you talking about the bright caps on the volume controls? Those are 120pF, C8 and C15.
A schematic, layout, and hi-rez pics are very useful for troubleshooting your amp. Don't wait to be asked. JUST DO IT!

Offline TerryD

  • Level 2
  • **
  • Posts: 304
Hoffman Amps Forum image
Re: Vox AC 30C2 Power tubes and diodes
« Reply #4 on: July 08, 2014, 05:04:38 pm »
Thanks for understanding my miscommunication.  AES= Antique Electronic supply I'm assuming.  thanks for the numbers

Offline TerryD

  • Level 2
  • **
  • Posts: 304
Hoffman Amps Forum image
Re: Vox AC 30C2 Power tubes and diodes
« Reply #5 on: July 09, 2014, 04:19:21 pm »
Just getting rid of c15 is an improvement.  Seemed to let a brittle high pitch through all the time.  Very nice amp

 


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


password