If you were going to build a OTL? - 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 14th November 2010, 07:49 PM   #1
dwhitf is offline dwhitf  United States
diyAudio Member
 
Join Date: May 2008
Send a message via Skype™ to dwhitf
Default If you were going to build a OTL?

If you were going to build a OTL (output-transformerless) amplifier and you knew you had to live with it long term which one would it be.
  Reply With Quote
Old 14th November 2010, 08:42 PM   #2
dwhitf is offline dwhitf  United States
diyAudio Member
 
Join Date: May 2008
Send a message via Skype™ to dwhitf
I made a mistake see other thread with voting, sorry for the Dup. thanks dwhitf
  Reply With Quote
Old 14th November 2010, 09:47 PM   #3
diyAudio Member
 
Miles Prower's Avatar
 
Join Date: May 2005
Location: USA
Blog Entries: 6
Quote:
Originally Posted by dwhitf View Post
If you were going to build a OTL (output-transformerless) amplifier and you knew you had to live with it long term which one would it be.
MOSFET Circlotron final, hollow state front end. The A Number One problem with any hollow state OTL is operating the finals into nearly vertical loadlines. That makes for big time distortion, and it becomes questionable whether that is preferable to just going ahead and using source followers. Just make sure that your source followers stay away from the rails since MOSFET internal capacitances go squirrelly when Vds drops to low voltages.

Besides, a MOSFET Circlotron doesn't need a high current heater transformer, nor does it require knocking a dozen holes in the chassis. There is also the safety question: the MOSFET design won't put bigvolts on the speaker terminals if something poofs.
__________________
There are no foxes in atheistholes
www.dolphin-hsl.com
  Reply With Quote
Old 14th November 2010, 10:14 PM   #4
kevinkr is offline kevinkr  United States
diyAudio Moderator
 
kevinkr's Avatar
 
Join Date: Sep 2004
Location: Boston, Massachusetts
Blog Entries: 6
Quote:
Originally Posted by dwhitf View Post
If you were going to build a OTL (output-transformerless) amplifier and you knew you had to live with it long term which one would it be.
I'd likely base it on one of Ralph Karsten's Atmosphere OTL amp designs, but more than likely I'd reconsider and probably go for a more conventional PP with an output transformer.
__________________
"Extraordinary claims require extraordinary evidence." - Carl Sagan
  Reply With Quote
Old 15th November 2010, 04:41 AM   #5
markusA is offline markusA  Sweden
diyAudio Member
 
markusA's Avatar
 
Join Date: Dec 2009
Location: Gothenburg
Blog Entries: 1
A M-60 seems like a likely candidate to me.
  Reply With Quote
Old 15th November 2010, 05:46 AM   #6
Luke is offline Luke  New Zealand
diyAudio Member
 
Join Date: Sep 2001
Location: Wellington NZ
Send a message via AIM to Luke
Quote:
Originally Posted by Miles Prower View Post
MOSFET Circlotron final, hollow state front end.
Hi Miles, do you have a link to this amp?
__________________
If you give a man a fish he will eat for a day. But if you teach a man to fish he will buy an ugly hat. And if you talk about fish to a starving man then you are a consultant. Dilbert
  Reply With Quote
Old 15th November 2010, 08:29 AM   #7
diyAudio Member
 
Miles Prower's Avatar
 
Join Date: May 2005
Location: USA
Blog Entries: 6
^^

Sure don't. It's a future project for someday. I haven't begun the design work for it.
__________________
There are no foxes in atheistholes
www.dolphin-hsl.com
  Reply With Quote
Old 15th November 2010, 08:36 AM   #8
Luke is offline Luke  New Zealand
diyAudio Member
 
Join Date: Sep 2001
Location: Wellington NZ
Send a message via AIM to Luke
Ah, it sounded interesting so I started googling and came up empty
__________________
If you give a man a fish he will eat for a day. But if you teach a man to fish he will buy an ugly hat. And if you talk about fish to a starving man then you are a consultant. Dilbert
  Reply With Quote
Old 15th November 2010, 08:39 AM   #9
Brit01 is offline Brit01  United Kingdom
diyAudio Member
 
Join Date: Jul 2008
I'm working on a OTL, circlotron final, FET source followers, LTP split, and experimenting with different front drivers right now and biasing techniques and protection.
  Reply With Quote
Old 15th November 2010, 08:44 AM   #10
CLS is offline CLS  Taiwan
diyAudio Member
 
Join Date: Jun 2005
Location: Taiwan
MOSFET Circlotron can be found at passdiy
  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
Seriously considering doing an OTL - but . . otto88 Tubes / Valves 18 7th October 2010 05:47 AM
Otl fdegrove Tubes / Valves 387 10th January 2009 06:39 PM
build my first full ranger,let's build another one:a small fullrange high end pc-spea then_dude Full Range 2 30th November 2005 07:54 AM
Do i need to build main supply (240v) filter?Or build power distribution? thomgun_lc Chip Amps 9 16th September 2005 09:52 AM
Otl ? woody Tubes / Valves 2 11th September 2003 04:44 PM


New To Site? Need Help?

All times are GMT. The time now is 01:25 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