Welcome To the Hoffman Amplifiers Forum

September 07, 2025, 07:36:27 pm
guest image
Welcome, Guest. Please login or register.
-User Name
-Password



Hoffman Amps Forum image Author Topic: creating a clean channel on a single channel amp  (Read 2509 times)

0 Members and 1 Guest are viewing this topic.

Offline martre

  • Level 1
  • *
  • Posts: 2
  • I love Tube amps
Hoffman Amps Forum image
creating a clean channel on a single channel amp
« on: April 19, 2021, 06:23:44 am »
Hello
I would ask to the experts if my idea to add a clean channel on a laney gh50 amp (circuit is very similar to the JCM800 2204) is correct. Attached my schematic, by a DPDT switch I would route the output from the 66k resistor and enter in V3, the V2 grid well be grounded. What do you think?

Offline PRR

  • Level 5
  • *******
  • Posts: 17082
  • Maine USA
Hoffman Amps Forum image
Re: creating a clean channel on a single channel amp
« Reply #1 on: April 19, 2021, 02:07:56 pm »
Welcome.

Grid of V3A needs to be well positive, like +150V DC. Your plan puts it at zero V DC. Gross distortion results.

Offline martre

  • Level 1
  • *
  • Posts: 2
  • I love Tube amps
Hoffman Amps Forum image
Re: creating a clean channel on a single channel amp
« Reply #2 on: April 19, 2021, 02:18:37 pm »
Thanks, do you have other suggestion?

Offline ac427v

  • Level 2
  • **
  • Posts: 347
  • I love tube amps
Hoffman Amps Forum image
Re: creating a clean channel on a single channel amp
« Reply #3 on: April 23, 2021, 08:17:31 am »
What about connecting at p14 instead of p18? The topology would be similar to a Plexi. My home-brew Plexi clean settings are my favorite. Volume on 2, Mids on 2, Master on 10.

 


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