Go Back   Home > Forums > >
Home Forums Rules Articles diyAudio Store Blogs Gallery Wiki 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

I have some 5654
I have some 5654
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 18th February 2007, 05:31 PM   #1
Hojvaelde is offline Hojvaelde  Denmark
diyAudio Member
 
Join Date: Jan 2005
Location: Denmark
Default I have some 5654

Hello

I have found some 5654

I can see 5654 is a low noise pentode.

I am planning a preamplifier with RIAA input. Can I use those tubes and if yes, does any have a schematic with 5654.

Regards

Benny
  Reply With Quote
Old 18th February 2007, 07:19 PM   #2
SY is offline SY  United States
On Hiatus
 
SY's Avatar
 
Join Date: Oct 2002
Location: Chicagoland
I have some 5654
A pentode will not be the last word in low noise. Whether giving up a few microvolts is worth it for some of the pentode virtues (especially regarding gain and Miller capacitance) is a much more subjective matter.
__________________
"You tell me whar a man gits his corn pone, en I'll tell you what his 'pinions is."
  Reply With Quote
Old 18th February 2007, 07:23 PM   #3
the_manta is offline the_manta  Germany
diyAudio Member
 
the_manta's Avatar
 
Join Date: Nov 2006
Location: Munich, Bavaria
5654 / EF95 / 6AK5W are bulk goods here in Germany. But nearly all of mine are very microphonic. So be carefull that you have good ones.

Simon
  Reply With Quote
Old 22nd February 2007, 04:29 PM   #4
Brian Beck is offline Brian Beck  United States
diyAudio Member
 
Brian Beck's Avatar
 
Join Date: Dec 2004
Location: South Florida, USA
I also have a number of 5654/6AK5/EF95 tubes, pulled from RF equipment. Given that these are sharp cut-off rather than remote cut-off devices, they stand a fighting chance of making fairly linear triodes, which is how youíd wire them for lowest noise, as SY says. I havenít tried them for audio, but they just might be worthwhile. The transconductance in pentode configuration is about 5000 uS at the data sheet bias values. With the screen tied to plate, that value would increase to over 6000 uS, a decently high value. Of course a 6DJ8 can double that value, but transconductance isnít everything. The triode mu of a 6AK5 is around 20, going by memory, which might be wrong. Often, for the first stage of RIAA, youíd want a bit more gain to increase the noise figure, but a medium mu tube is still a possibility depending upon your other circuit choices. I believe that triode-wired 6AK5s were used happily in some tube microphones, but factors like physical size and heater power requirements might have also influenced those choices. Why not give it a try and let us know how it worked?
__________________
Brian
  Reply With Quote

Reply


I have some 5654Hide 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

Forum Jump

Similar Threads
Thread Thread Starter Forum Replies Last Post
Tube Buffer 6J1 / 5654 (6AK5) Cobra2 Tubes / Valves 104 9th April 2016 06:39 PM
6ak5/5654 plate resistance rauze Tubes / Valves 7 17th September 2008 03:28 AM


New To Site? Need Help?

All times are GMT. The time now is 03:12 PM.


Search Engine Optimisation provided by DragonByte SEO (Pro) - vBulletin Mods & Addons Copyright © 2018 DragonByte Technologies Ltd.
Resources saved on this page: MySQL 16.67%
vBulletin Optimisation provided by vB Optimise (Pro) - vBulletin Mods & Addons Copyright © 2018 DragonByte Technologies Ltd.
Copyright ©1999-2018 diyAudio
Wiki