6EJ7 phono preamp? - diyAudio
Go Back   Home > Forums > Amplifiers > Tubes / Valves

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
Reply
 
Thread Tools Search this Thread
Old 6th March 2008, 01:37 PM   #1
diyAudio Member
 
Join Date: Sep 2007
Default 6ej7 Phono preamp?

Would it be possible to build a MM phono preamp using the 6ej7? Has it been done?
__________________
Born in the wrong decade.
  Reply With Quote
Old 7th March 2008, 12:19 AM   #2
diyAudio Member
 
Join Date: Apr 2004
Location: Monroe Township, NJ
I have no idea if it has been tried. I can see a 6EJ7 in the 2nd gain block role of a passive EQ phono preamp. A CCS loaded 6922 in the 1st gain block role should provide enough gain to get past pentode partition noise effects.

Look at the data sheet. Notice that both gm and RP are high. A DC coupled voltage follower is needed between the 6EJ7 and the O/P jack.
__________________
Eli D.
  Reply With Quote
Old 14th September 2014, 11:03 PM   #3
rmb is offline rmb  United States
diyAudio Member
 
Join Date: Nov 2012
Location: western PA
Anyone used a 6EJ7 triode connected in mic or phono preamp? Any curves available for the 6EJ7 triode connected?
  Reply With Quote
Old 15th September 2014, 12:03 AM   #4
diyAudio Member
 
Join Date: Sep 2014
There have been many preamps (phono&mic) that have used pentodes. 6AU6, 5879,EF86/6267,6J7 etc. Most of these were originally designed for these applications,and some had low noise/low microphonic versions available. The 6EJ7,and it's 'brother',the 6EH7, were NOT. These tubes were designed for extremely high gain in intermediate frequency amplifiers in television sets and other tuner applications,in an effort to reduce the number of tubes and tuned circuits and therefore reduce cost. Most,if not all examples,are horribly noisy.They were never intended for audio work,and these problems have no effect in their designed for application. I had the same idea as you many years ago,as I did a great deal of work for recording studios,and had on hand dozens of these,mostly NIB Amperex.We were trying to find substitutes for the other types,as they were very hard to get at that time. Complete waste of time and effort. You may get lucky and find a quiet one,but that'll be a total fluke!
  Reply With Quote

Reply


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
Any designs for 6EJ7 out there? leadbelly Tubes / Valves 8 27th September 2012 06:23 PM
new phono stage or old preamp with phono? flohmann Analog Line Level 2 2nd October 2008 09:51 PM
Electret mic preamp - will phono preamp work? darthmullet Analogue Source 6 12th October 2007 07:32 AM
6EJ7 or 6EH7 triode strapped? kegger Tubes / Valves 11 29th November 2006 08:45 AM
MC phono preamp Vortex Tubes / Valves 29 29th March 2004 10:39 AM


New To Site? Need Help?

All times are GMT. The time now is 08:08 AM.


vBulletin Optimisation provided by vB Optimise (Pro) - vBulletin Mods & Addons Copyright © 2014 DragonByte Technologies Ltd.
Copyright 1999-2014 diyAudio

Content Relevant URLs by vBSEO 3.3.2