One more 4P1L SE - Page 37 - 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 10th January 2013, 11:42 AM   #361
regal is offline regal  United States
diyAudio Member
 
Join Date: Jan 2004
Location: MD
Quote:
Originally Posted by merlin el mago View Post
I know one person in Spain how makes hand made grain orientated, can't be enough? what about Lundhal LL1689 http://www.lundahl.se/pdf/1689.pdf, can be wired 9:1 or 18:1?
I think Lundhal C-core is what I am leaning toward since they have less signal loss, with senns and grados we are dealling with small millwatts and detail is lost without the right transformer, all I can say is don't go for a transformer with high DCR secondary, it makes the output tube work and distort way more than it has too. I honestly know just enough about transformer design to be dangerious, but none of us set headphone geeks have pooled our resources to find the right transformer winder who uderstands our needs.

As much as I like the single -feed design I proposed I suspect that a parafeed nckel core OPT would sound better, just don't have the answers for you unfortunately.

The real classic headphone iron is the Peerless TL-404 autoformer parafeed, but they are hard to find. If enough of us asked magnequest perhaps they would make a batch.

Maybe some of the preamp guys can share some light on the subject ?
  Reply With Quote
Old 10th January 2013, 01:10 PM   #362
iko is online now iko  Canada
diyAudio Moderator
 
iko's Avatar
 
Join Date: May 2008
Location: Toronto
Regular C cores from Silicon Steel C-Cores / Goss C-Cores for 60 Hz and 50/60 Hz Frequencies wouldn't work?
  Reply With Quote
Old 10th January 2013, 03:35 PM   #363
diyAudio Member
 
merlin el mago's Avatar
 
Join Date: Sep 2009
Location: Catalonia - Europe
I need to know the B+ voltage 150V or 200V to know wich voltage for filament bias is necessary 10V or 15V?
  Reply With Quote
Old 10th January 2013, 03:46 PM   #364
diyAudio Member
 
nicoch58's Avatar
 
Join Date: Oct 2004
merlin ecp audio diy: Designing a Parafeed Headphone Amplifier
__________________
Sic58
  Reply With Quote
Old 10th January 2013, 04:02 PM   #365
diyAudio Member
 
merlin el mago's Avatar
 
Join Date: Sep 2009
Location: Catalonia - Europe
Thanks / Grazie Nico.
  Reply With Quote
Old 10th January 2013, 04:29 PM   #366
diyAudio Member
 
merlin el mago's Avatar
 
Join Date: Sep 2009
Location: Catalonia - Europe
I have one Bartolucci C-Core 125VAC so I will use 150V B+
  Reply With Quote
Old 10th January 2013, 05:01 PM   #367
diyAudio Member
 
merlin el mago's Avatar
 
Join Date: Sep 2009
Location: Catalonia - Europe
Pic with supposed schematic? could anybody draws or link me to the DN2540 cascode?
Attached Images
File Type: jpg DHT Headamp 4P1L 1st attempt.jpg (191.4 KB, 325 views)
  Reply With Quote
Old 10th January 2013, 05:18 PM   #368
diyAudio Member
 
merlin el mago's Avatar
 
Join Date: Sep 2009
Location: Catalonia - Europe
Updated pic, it's OK? starved filaments 1.8V
Attached Images
File Type: jpg DHT Headamp 4P1L 1st attempt.jpg (194.5 KB, 311 views)

Last edited by merlin el mago; 10th January 2013 at 05:27 PM.
  Reply With Quote
Old 10th January 2013, 05:52 PM   #369
iko is online now iko  Canada
diyAudio Moderator
 
iko's Avatar
 
Join Date: May 2008
Location: Toronto
Resistor from grid of second tube to ground needed. I'd also add grid stopper resistors to safeguard against oscillations.
  Reply With Quote
Old 10th January 2013, 06:13 PM   #370
diyAudio Member
 
merlin el mago's Avatar
 
Join Date: Sep 2009
Location: Catalonia - Europe
Quote:
Originally Posted by ikoflexer View Post
Resistor from grid of second tube to ground needed. I'd also add grid stopper resistors to safeguard against oscillations.
Grid stopper resistors in both tubes? wich value & power?

Attached updated schematic.
Attached Images
File Type: jpg DHT Headamp 4P1L 1st attempt.jpg (196.2 KB, 263 views)
  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
pentode in triode mode SE vs a DHT SE like 2a3/300b jarthel Tubes / Valves 67 8th July 2014 01:51 AM
Russian-English Translation of 4P1L datasheet 316a Tubes / Valves 16 6th September 2011 12:09 AM
Rare audiophile stereo tube SE amplifier DIY kit (6C2C + 4P1L). mik190 Swap Meet 7 1st November 2010 07:59 AM
Can the Golden Tube Audio SE-40 SE drive 16 ohm woofers? nelsondog Everything Else 1 11th November 2007 05:00 PM
Parallel SE vs. Single SE Output Question valveitude Tubes / Valves 19 4th May 2005 05:36 PM


New To Site? Need Help?

All times are GMT. The time now is 10:46 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