Welcome To the Hoffman Amplifiers Forum

September 08, 2025, 03:37:55 am
guest image
Welcome, Guest. Please login or register.
-User Name
-Password



Hoffman Amps Forum image Author Topic: Tungsten Crema Wheat  (Read 8285 times)

0 Members and 1 Guest are viewing this topic.

Offline Leevi

  • Level 3
  • ***
  • Posts: 1574
  • I love tube amps
    • Rikstone
Hoffman Amps Forum image
Tungsten Crema Wheat
« on: January 23, 2013, 03:14:50 pm »
This amp is like 5E3 but there has been added some modifications like
possibility to use 6L6 and E34? Also the tone pot is implemented with a dual pot.
Rectifier is GZ34 instead of 5Y3.

Does anyone know the specifications of the PT (or B+)?

/Leevi

Offline dwight

  • Level 1
  • *
  • Posts: 2
Hoffman Amps Forum image
Re: Tungsten Crema Wheat
« Reply #1 on: January 24, 2013, 10:04:13 am »
I don't have any specifics about that PT. I know it's a custom Mercury Magnetics.  Some detailed gut shots can be found here:
http://www.thegearpage.net/board/showthread.php?t=906560


I actually modded my 5e3 to be pretty close to the Crema Wheat, using those photos.  It was just a couple extra changes over the regular volume/tone mod, including split cathodes on V1, 150k plate resistors on V1, 47nF coupling caps, and 360R/25uF on the power tube cathodes.  Oh, and it has 30uF filter caps all the way across.  It wasn't really my thing in the end, and I went back to something closer to stock.

The Allen TP40D looks like a nice choice for a high-powered 5e3 though, IMHO.

Offline Leevi

  • Level 3
  • ***
  • Posts: 1574
  • I love tube amps
    • Rikstone
Hoffman Amps Forum image
Re: Tungsten Crema Wheat
« Reply #2 on: January 24, 2013, 02:21:37 pm »
360R instead of 250R on the cathode might mean a higher plate voltage than in 5E3?
I'm planning to use EL34s as well. I have thought to use the 16 Ohm output with 8 Ohm speaker
in order the get the load resistance to right level.
/Leevi

Offline plexi50

  • Level 4
  • *****
  • Posts: 4649
  • Tube Tone
Hoffman Amps Forum image
Re: Tungsten Crema Wheat
« Reply #3 on: January 24, 2013, 03:32:02 pm »
It wasn't really my thing in the end, and I went back to something closer to stock:

Thats one thing i have learned over all these years. Mods are interesting and fun to do. But in the end it all comes back to the original old Fender,Marshall,Valco,Gibson,Ampeg Gemini,Silvertone etc tones.

Offline dwight

  • Level 1
  • *
  • Posts: 2
Hoffman Amps Forum image
Re: Tungsten Crema Wheat
« Reply #4 on: January 24, 2013, 06:04:09 pm »
360R instead of 250R on the cathode might mean a higher plate voltage than in 5E3?

The GZ34 that comes "stock" with the Crema Wheat would give a higher B+ even with a standard Deluxe PT than would a 5y3.  I don't know if the Crema PT actually has higher voltage secondaries or not.  With 6V6's, a GZ34, and a Deluxe-style PT, I was getting a B+ up around 375 V, so there's not a whole lot of room left to go if you were gonna keep 6v6's in there.

Thats one thing i have learned over all these years. Mods are interesting and fun to do. But in the end it all comes back to the original old Fender,Marshall,Valco,Gibson,Ampeg Gemini,Silvertone etc tones.

Yep. One of these days I'll learn, but not just yet.

Offline Leevi

  • Level 3
  • ***
  • Posts: 1574
  • I love tube amps
    • Rikstone
Hoffman Amps Forum image
Re: Tungsten Crema Wheat
« Reply #5 on: January 26, 2013, 03:37:31 pm »
Quote
I actually modded my 5e3 to be pretty close to the Crema Wheat, using those photos.  It was just a couple extra changes over the regular volume/tone mod, including split cathodes on V1, 150k plate resistors on V1, 47nF coupling caps, and 360R/25uF on the power tube cathodes.  Oh, and it has 30uF filter caps all the way across.  It wasn't really my thing in the end, and I went back to something closer to stock.

I got the chassis wired and I wonder the different capacitor values 10n and 22n around the dual pot?
Another question is how the dual Tone pot should be wired and what are the capacitor values?

http://s710.beta.photobucket.com/user/L4CESN/media/Tungsten%20Crema%20Wheat/IMG_0251.jpg.html?sort=3&o=11

/Leevi
« Last Edit: January 26, 2013, 03:53:30 pm by Leevi »

Offline Willabe

  • Global Moderator
  • Level 5
  • ******
  • Posts: 10524
Hoffman Amps Forum image
Re: Tungsten Crema Wheat
« Reply #6 on: January 26, 2013, 04:10:40 pm »
I think Ed Chambley did that dual pot TS to 1 of his 5E3 amps.

        
            Brad     :icon_biggrin:
« Last Edit: January 26, 2013, 04:12:51 pm by Willabe »

Offline printer2

  • Level 2
  • **
  • Posts: 235
Hoffman Amps Forum image
Re: Tungsten Crema Wheat
« Reply #7 on: January 26, 2013, 06:32:43 pm »
For those that want the option to switch between the interactive 5E3 controls or non-interactive (only tone control on the instrument channel) the following will do it for you.



And a couple ways of wiring the mod.


Offline Leevi

  • Level 3
  • ***
  • Posts: 1574
  • I love tube amps
    • Rikstone
Hoffman Amps Forum image
Re: Tungsten Crema Wheat
« Reply #8 on: January 27, 2013, 05:07:18 am »
Quote
I think Ed Chambley did that dual pot TS to 1 of his 5E3 amps.

I changed the TS accoding to that and IMO it works pretty well.
http://www.el34world.com/Forum/index.php?topic=14297.0

If you wonder the switch close to the outputs it's used to set EL34 mode when using EL34 power tubes.

Thanks
/Leevi
« Last Edit: January 27, 2013, 07:10:18 am by Leevi »

 


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