The Emperor's New Amplifier - 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 24th September 2003, 04:34 PM   #1
diyAudio Member
 
Join Date: Sep 2003
Location: Santa Monica
Default The Emperor's New Amplifier

Have anyone any experience building TENA, any good reason till that I shouldn't?

http://www.normankoren.com/Audio/TENA.html

/Magnus
__________________
Helpless in US
  Reply With Quote
Old 25th September 2003, 02:15 PM   #2
diyAudio Moderator Emeritus
 
Bas Horneman's Avatar
 
Join Date: Apr 2002
Location: The Netherlands
Blog Entries: 18
If your nom de plume has any truth in it, then don't build it.

It is a relatively complex design and if you have to ask then you should not build it.

Regards,
Bas
  Reply With Quote
Old 25th September 2003, 03:08 PM   #3
diyAudio Member
 
Join Date: May 2002
Location: Plano , TX
Send a message via AIM to jewilson
Default Nice Amp

I like the design; I do not believe that toroidal output transformer is required. It true they have more bandwidth and there also can pass more noise and most tube amps do not use them.

I like the regulation and the bias designs. However, I am not the fond of his use of local feedback on the front gain stages. In addition, his layout is a little crude. All in all it an ok design, but there are a lot of nice tube design around
__________________
Jim W.
  Reply With Quote
Old 25th September 2003, 03:31 PM   #4
diyAudio Member
 
Join Date: Sep 2003
Location: Santa Monica
Well I wasn't thinking of the complexity, more if someone had built it and had any experiences of the sound.

But you are probebly right, I shouldn't built it when I lack experience building tube amps.

As for the name, you never know!

Adjö

/Magnus
__________________
Helpless in US
  Reply With Quote
Old 25th September 2003, 03:45 PM   #5
diyAudio Moderator Emeritus
 
Bas Horneman's Avatar
 
Join Date: Apr 2002
Location: The Netherlands
Blog Entries: 18
Quote:
But you are probebly right, I shouldn't built it when I lack experience building tube amps
That is not what I meant...I meant that you should rather build something simpler ....I have built a couple of amps before...but that schematic looks very daunting to me...with all the bias circuits and regulators....etc, etc. even the main amp itself is complex as far as I am concerned...

Cheers,
Bas
  Reply With Quote
Old 25th September 2003, 05:51 PM   #6
diyAudio Member
 
Join Date: Sep 2003
Location: Santa Monica
I understand that you didn't mean it like that.

And yes it is pretty complex!

/Magnus
__________________
Helpless in US
  Reply With Quote
Old 3rd January 2012, 02:25 PM   #7
heb1001 is offline heb1001  China
diyAudio Member
 
Join Date: Sep 2011
Default TENA 3

I built a variant of TENA - the reduced feedback version.

I did my own layout for the components. I also changed the input stage to be fully balanced and used locally sourced toroidal output transformers which limit the frequency response to 27kHz. I also used KT88s.

This was my first tube amp build. It sounds good to me.

Some lessons learned:

12AU7s work OK (and look pretty) but 6SN7s are more linear and result in lower distortion so stick with 6SN7s. I'm now using a 6SN7 in an adapter for TU3 and TU4 and using 12AU7s for the others. This combination is OK.

I think electrolytics CBX1, 2 and 3 and CB5 should have the positive side connected to ground (the bias voltage on the other side is negative).

I used 6.8K for R3F.

The protective diodes mentioned in the text are essential. There are some for the MOSFETs and some protecting the bias servo op amp inputs. They are shown in the layout diagrams but not the circuit diagrams.
Attached Images
File Type: jpg P1020281.jpg (991.6 KB, 313 views)
  Reply With Quote
Old 3rd January 2012, 03:39 PM   #8
DF96 is online now DF96  England
diyAudio Member
 
Join Date: May 2007
The amplifier name would put me off. We know the emperor's new clothes were not quite what they were claimed to be, so why build an amp which might suffer from the same problem?
  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
Exstroyer x Amplifier...Ex amp...my amplifier MJL21193 Solid State 131 28th July 2009 01:26 PM
Wanted: DIY amplifier builder with experience. I need a 0.7 ohm stable amplifier Audiophilenoob Swap Meet 34 16th May 2005 11:58 PM
Questions about how to decrease the PASS A-40 amplifier into a class AB amplifier. novtango Pass Labs 2 21st October 2002 01:50 AM


New To Site? Need Help?

All times are GMT. The time now is 09:49 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