Welcome To the Hoffman Amplifiers Forum

September 07, 2025, 12:17:04 pm
guest image
Welcome, Guest. Please login or register.
-User Name
-Password



Hoffman Amps Forum image Author Topic: Kt66 cathode bias what opt  (Read 2390 times)

0 Members and 1 Guest are viewing this topic.

Offline Scsoul

  • Level 1
  • *
  • Posts: 59
Hoffman Amps Forum image
Kt66 cathode bias what opt
« on: September 21, 2016, 02:29:28 pm »
  I could use 350 plate voltage or 400 on the plates, I have a heyboer 5.9k 40watt ot or 4k
40watt the preamp will basicly be a jtm45 with cathiode biased kt66

Offline ToneJunkie

  • Level 2
  • **
  • Posts: 113
  • Don't forget to play
Hoffman Amps Forum image
Re: Kt66 cathode bias what opt
« Reply #1 on: September 21, 2016, 10:10:46 pm »
I would like to see some suggestions for this too... I'm about to buy iron for a similar project.  Although I think I'm gonna start with fixed bias and move to cathode bias if i need some more sag/compression.  I will probably have more voltage not he plates too... So no suggestions from me just another interested party :-)

Offline PRR

  • Level 5
  • *******
  • Posts: 17082
  • Maine USA
Hoffman Amps Forum image
Re: Kt66 cathode bias what opt
« Reply #2 on: September 21, 2016, 10:23:11 pm »
350V and 4K-5K
-or-
400V 6K-7K

I know a happy cathode bias for the 400V case. Do you have a clue what resistor for the 350V and lower-Z case?

Offline tubeswell

  • Level 4
  • *****
  • Posts: 4202
  • He who dies with the most tubes... wins
Hoffman Amps Forum image
Re: Kt66 cathode bias what opt
« Reply #3 on: September 22, 2016, 12:46:28 am »
Seems like a waste running KT66s at 350. (Just saying.)
A bus stops at a bus station. A train stops at a train station. On my desk, I have a work station.

 


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