3B7 Loctal DHT - 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 3rd March 2009, 07:50 AM   #1
Klimon is offline Klimon  Belgium
diyAudio Member
 
Join Date: Apr 2005
Location: Leuven
Default 3B7 Loctal DHT

Looking for curves / operation points / testimonies about this tube.

Thanks!

Simon
  Reply With Quote
Old 3rd March 2009, 11:08 AM   #2
diyAudio Member
 
Join Date: May 2007
http://frank.pocnet.net/sheets/127/3/3B7.pdf

Curves look nice from 2-3mA and up. Ra should be in the ballpark of 10kohm.

Why not parallell the halves for a transformer coupled (4:1) SE pre?

  Reply With Quote
Old 3rd March 2009, 11:20 AM   #3
diyAudio Member
 
Join Date: Sep 2003
Location: London
I tried using the 3B7 but found it harsh. I didn't scope it, so there's a real possibility that it was oscillating and needed a bigger grid stopper. So if you have a go at listening to one, put a decent size grid stopper on it.

andy
  Reply With Quote
Old 3rd March 2009, 11:22 AM   #4
diyAudio Member
 
Join Date: May 2007
Thanks Andy,

Is there a DHT you haven´t tried ?

By the way, are they easy to find?
  Reply With Quote
Old 3rd March 2009, 12:18 PM   #5
diyAudio Member
 
Join Date: Sep 2003
Location: London
Is there a DHT I haven't tried?

Yes - megabuck ones like the 50, and esoteric new production.

Also I haven't yet tried out the European ones I've been buying - RE034, 074, 084, 134

But seriously, there were loads of different DHTs made. I've probably tried most of the popular ones which were about in large quantities.

I think the 3B7 is quite easy to get - dealers should have them.

andy
  Reply With Quote
Old 4th March 2009, 06:48 AM   #6
Klimon is offline Klimon  Belgium
diyAudio Member
 
Join Date: Apr 2005
Location: Leuven
Interesting, thanks!

Simon
  Reply With Quote
Old 4th March 2009, 10:21 AM   #7
nafunga is offline nafunga  United Kingdom
diyAudio Member
 
Join Date: Jul 2005
Location: Whitstable , Kent. UK
Default DHT

Regarding DHT small signal types available in the UK, the LP2, PM2A etc, range of 2v filament valves are readily available from the usual sources i.e, Colomor and Langrex. The types mentioned were originally designed for audio output stages (approx. 0.1W) but make very good drivers for larger rated types. I use them to drive VT-25's etc. They work well.

Regards,

David.
  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
Are there any loctal PC sockets? Joku Tubes / Valves 2 18th May 2009 02:55 AM
Is there a LOCTAL equiv to a 6V6? grhughes Tubes / Valves 16 13th March 2009 12:53 AM
Loctal Rectifiers dsavitsk Tubes / Valves 2 30th January 2008 10:24 PM
Loctal 6SN7? pftrvlr Tubes / Valves 11 21st January 2008 04:45 PM
PCB Mount Loctal Socket? dsavitsk Tubes / Valves 0 10th March 2007 12:17 AM


New To Site? Need Help?

All times are GMT. The time now is 04:46 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