6HV5A Single Ended Amp - Page 8 - 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 16th June 2010, 02:29 AM   #71
diyAudio Member
 
tubelab.com's Avatar
 
Join Date: Jul 2005
Location: West Virginia panhandle
Quote:
Or is it just that cliplead parasitics are driving you nuts?
I have been told over and over that you can't build an amp using clip leads. I have never been one to listen very well so I did it......about a zillion times. Yes there are some tubes that you CAN'T clip lead together the 5842 / 417A is one and the 6EJ7 is another. It appears that the 6HV5 and friends are also on this list. Note that tubes with lots of transconductance seem to be clip lead unfriendly.

Note the method of construction used in these fully functional amps.


Quote:
As for 6HV5, might see if its any more stable when Schaded to lower Mu? Particularly DC coupled 100% PG without voltage gain. That could be an
interesting mode of operation in A2, if you could toss some direct coupled
sand between Schade and Grid without a phase shift back to instability???
That is where I may go next. Reduce the gain AND the output impedance via local feedback to make a $1 triode sound like a $50 triode.

Quote:
Waitaminute... I got 13pin sockets.
Then you really have something weird, since they should be 12 pin sockets. Others have suggested sky wiring octal or 9 pin sockets into this board, but that is too much work. There are dozens of 12 pin tubes that work in this board, many of them cheap. 6GV5's were on the dollar menu until this board came along.

Tube testers may tell you what the Gm is under rather low powered conditions. They don't tell you much about waht happens at 30 watts though.
Attached Images
File Type: jpg Furball_operational.jpg (331.6 KB, 365 views)
File Type: jpg 6CD6GAtest.jpg (107.3 KB, 342 views)
File Type: jpg DontTryThisAtHome_A.jpg (265.2 KB, 319 views)
__________________
Too much power is almost enough! Turn it up till it explodes - then back up just a little.
  Reply With Quote
Old 16th June 2010, 02:45 AM   #72
diyAudio Member
 
wrenchone's Avatar
 
Join Date: Feb 2004
Location: Silicon Valley
I agree that a 6HV5 or one of its siblings might be a natural for a partial feedback (Schade-style) amp as a way of utilizing all that excess gain. I was thinking of a modest triode-pentode pair (people can insert their faves) for the front end, with the pentode as voltage amp and the triode as cathode follower to direct drive the grid. I would look for a tube that had a medium-mu, relatively high gm triode (get out your tube manuals). The amp might end up with enough feedback, even with a Schade-style setup, to sound solid state-ish...
  Reply With Quote
Old 19th June 2013, 02:01 PM   #73
diyAudio Member
 
Vinylsavor's Avatar
 
Join Date: Feb 2002
Location: Lindau
Hi!

Ever wondered how such a beam triode looks inside?

Check out my post about this tube with photos of the grid:

VinylSavor: Tube of the Month : The 6HV5A

Best regards

Thomas
__________________
http://vinylsavor.blogspot.com/
  Reply With Quote
Old 20th June 2013, 02:02 AM   #74
diyAudio Member
 
Join Date: May 2007
Thanks Thomas, very interesting!
  Reply With Quote
Old 20th June 2013, 03:06 AM   #75
multi is offline multi  Australia
diyAudio Member
 
Join Date: Jan 2011
Default 811A SE

Nobu Shishido's SE using the 811A
430 volts supply for 13.5 watts. 3.5K transformer
I made a 811A SE but used a 6BX7 as a cathode follower to drive it.
Fewer transformers the better.!!!
Phil
Attached Images
File Type: jpg 811A SE.jpg (348.3 KB, 125 views)
  Reply With Quote
Old 20th June 2013, 04:55 AM   #76
diyAudio Member
 
wrenchone's Avatar
 
Join Date: Feb 2004
Location: Silicon Valley
The 6HV5A must have been one of the largest frame grid triodes ever made. I wonder what the reject rate was on those tubes - maybe they had a special jig for grid-to-cathode spacing.
  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
Single Ended, Single driver: In-room distortion measurements Gerrit Boers Full Range 4 27th November 2007 08:12 AM
Single Ended EL-34? jaymanaa Tubes / Valves 11 28th March 2006 10:32 PM
42 single ended ThSpeakerDude88 Tubes / Valves 38 19th November 2005 10:02 PM
Anyone play with the Zen Single-Stage Single-Ended Class A? Rino odorico Pass Labs 13 29th August 2002 09:01 AM


New To Site? Need Help?

All times are GMT. The time now is 10:25 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