Welcome To the Hoffman Amplifiers Forum

September 07, 2025, 04:03:27 pm
guest image
Welcome, Guest. Please login or register.
-User Name
-Password



Hoffman Amps Forum image Author Topic: Extracting a Single Channel - Mixers, Gain and Blocking  (Read 1781 times)

0 Members and 1 Guest are viewing this topic.

Offline fiftynine

  • Level 2
  • **
  • Posts: 151
Hoffman Amps Forum image
Extracting a Single Channel - Mixers, Gain and Blocking
« on: February 12, 2017, 05:20:40 am »
What's everyones opinions on leaving the mixing resistors and grounded resistor (in say the AB763) when extracting the normal channel? If you went straight into the 0.001, would you get more power-amp clipping (the reverse effect of a master volume) which always sounds good to my ears? Will removing those components lead to instability and/or blocking distortion or will it open up the amp? Or, is this point in the circuit the perfect place to tame gain? Is there anywhere else better suited to reduce gain if needed?


Thanks.
« Last Edit: February 12, 2017, 07:38:55 am by fiftynine »

Offline sluckey

  • Level 5
  • *******
  • Posts: 5075
    • Sluckey Amps
Hoffman Amps Forum image
Re: Extracting a Single Channel - Mixers, Gain and Blocking
« Reply #1 on: February 17, 2017, 06:18:25 am »
If you go straight into the LTPPI input cap you will have more signal available to drive the power amp. Could be up to twice the signal level, depending on the particular circuit. You'll be able to hear a little more grind on an AB763 Deluxe Reverb if you turn the volume up. But you'll lose that grind if you turn the volume down. I've never experienced any instability or blocking distortion.
A schematic, layout, and hi-rez pics are very useful for troubleshooting your amp. Don't wait to be asked. JUST DO IT!

Offline fiftynine

  • Level 2
  • **
  • Posts: 151
Hoffman Amps Forum image
Re: Extracting a Single Channel - Mixers, Gain and Blocking
« Reply #2 on: February 20, 2017, 06:39:40 am »
Oh the stress of retaining redundant parts vs loosing vintage mojo.


Thanks as always, Sluckey.

 


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