12AU7 -> 12BH7 Do I need to change Rp? - diyAudio
Go Back   Home > Forums > Amplifiers > Tubes / Valves
Home Forums Rules Articles diyAudio Store Gallery Wiki Blogs Register Donations FAQ Calendar Search Today's Posts Mark Forums Read

Tubes / Valves All about our sweet vacuum tubes :) Threads about Musical Instrument Amps of all kinds should be in the Instruments & Amps forum

Please consider donating to help us continue to serve you.

Ads on/off / Custom Title / More PMs / More album space / Advanced printing & mass image saving
Thread Tools Search this Thread
Old 28th February 2005, 04:06 PM   #1
zxx123 is offline zxx123  United States
diyAudio Member
Join Date: Aug 2003
Location: ca
Default 12AU7 -> 12BH7 Do I need to change Rp?

I have a 12AU7 preamp. From an article in this diyaudio, I change 12AU7 into 12BH7. <p>Wow, I feel wider sound range and more linearity. <p>However, I hear more white noise....I think it gives more gain.<br>Do I need to change Rp for original 12AU7?
  Reply With Quote
Old 28th February 2005, 05:30 PM   #2
SY is offline SY  United States
On Hiatus
SY's Avatar
Join Date: Oct 2002
Location: Chicagoland
Blog Entries: 2
You might need to change the cathode resistor. What are the current values of Rk and Rp? And what is the B+?
"You tell me whar a man gits his corn pone, en I'll tell you what his 'pinions is."
  Reply With Quote
Old 28th February 2005, 05:38 PM   #3
zxx123 is offline zxx123  United States
diyAudio Member
Join Date: Aug 2003
Location: ca
Default Well..


I do not open it yet because I need a special tool. So, I did not know its exact values of resistors.
(star wrench)

How about this? 12AU7 is used for PI of 6V6PP. If I feel 12BH7 better than 12AU7, I will abolish all 12AU7s in my system.
  Reply With Quote
Old 3rd March 2005, 12:41 PM   #4
Tubesin is offline Tubesin  Macao
diyAudio Member
Join Date: Sep 2004
Location: macao
Usually U7 and BH7 can be exchanged without any change to the components value, special in a preamp, however, have you checked the BH7 is noisy or not?
  Reply With Quote


Hide this!Advertise here!
Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off

Similar Threads
Thread Thread Starter Forum Replies Last Post
12AU7 vs 12BH7 vs 6CG7 SHiFTY Tubes / Valves 42 17th November 2011 03:05 PM
12AU7/12BH7 Headphone Amp sorenj07 Headphone Systems 42 16th June 2007 12:14 AM
12BH7 Specs sauuuuuce Tubes / Valves 2 16th September 2004 12:22 AM
12BH7 is microphonic Burnedfingers Tubes / Valves 7 1st May 2003 10:35 PM

New To Site? Need Help?

All times are GMT. The time now is 09:14 AM.

vBulletin Optimisation provided by vB Optimise (Pro) - vBulletin Mods & Addons Copyright © 2017 DragonByte Technologies Ltd.
Copyright 1999-2017 diyAudio

Content Relevant URLs by vBSEO 3.3.2