Go Back   Home > Forums > Amplifiers > Solid State

Solid State Talk all about solid state amplification.

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 25th May 2005, 06:10 PM   #1
diyAudio Member
 
Join Date: Sep 2004
Location: Göteborg
Default McIntosh Unity Gain with SolidState???

Anyone built an SS version of McIntosh unity gain transformer coupled output stage?
I think its a brilliant solution and Im thinking of winding a transformer to try it.
Any thoughts, ideas or experience is appreciated!
__________________
We live in a horizontal world, why use vertical topologies???
  Reply With Quote
Old 26th May 2005, 12:33 AM   #2
diyAudio Member
 
Join Date: Feb 2001
Location: Columbia, SC
The tube McIntosh designs used a unique output transformer that had extra taps on it for feedback to earlier stages. Their solid state designs don't use transformers in the usual sense; they're autoformers. To the best of my knowledge, no other company uses such a thing at this time.
Can an autoformer be done on a DIY basis. Absolutely. And that's pretty much the only way it'll happen. I'm not aware of any transformer manufacturer that offers such a thing in their standard product line. McIntosh used to (and I believe they still do) build their own.

Grey
  Reply With Quote
Old 26th May 2005, 12:45 AM   #3
diyAudio Member
 
john curl's Avatar
 
Join Date: Jul 2003
Location: berkeley ca
I don't think that a solid state version would be useful. You must try to understand why the unity coupled circuit was invented in the first place.
  Reply With Quote
Old 26th May 2005, 12:47 AM   #4
SY is offline SY  United States
diyAudio Moderator
 
SY's Avatar
 
Join Date: Oct 2002
Location: Chicagoland
Blog Entries: 1
GR, if I'm not mistaken, Atmasphere offers an autotransformer as an accessory. And as John intimated, notch distortion is not an issue.
__________________
"It is difficult to get a man to understand something, when his salary depends upon his not understanding it." — Upton Sinclair
  Reply With Quote
Old 26th May 2005, 02:14 AM   #5
diyAudio Member
 
Join Date: Feb 2001
Location: Columbia, SC
Now that you mention it, I think I remember seeing something about that. I bet they roll their own, too.

Grey
  Reply With Quote
Old 26th May 2005, 06:04 AM   #6
diyAudio Member
 
Join Date: Sep 2004
Location: Göteborg
Thanks for answer!
Im not intrested in the autotransformer, but in their original pentode with unitygain coupling and crosscoupled screengrids. When thinking about it it seems to work as a cascoded cathodefollower. The Cathode-Screengrid voltage being constant, and 100 % local feedback.

Im just fooling around trying to learn all about balanced circuits. I found this one very intresting, and I think its a worthwhile expirment translating it to solidstate.

Johannes
__________________
We live in a horizontal world, why use vertical topologies???
  Reply With Quote
Old 26th May 2005, 06:16 AM   #7
AJT is offline AJT  Philippines
diyAudio Moderator
 
AJT's Avatar
 
Join Date: May 2003
Location: Palatiw, Pasig City
for tubes it makes a lot of sense, but for solid state, what for? speaker impedance levels are within reach of solid state state circuitry anyway...
  Reply With Quote
Old 26th May 2005, 08:31 AM   #8
diyAudio Member
 
Join Date: Sep 2004
Location: Göteborg
The exact same reason im building amps in the first place: Its fun!
I know there is no real good reason to experiment with all kinds of strange circuits. Its better and much simpler buying a Krell or PassLabs X-350.
I like transformers in the output section of amps. They make the amps safe and easy to build. Dc offset is no big problem.No loudspeaker protection needed and they seem to sound very good. Se Susan Parkers Zeus!
I like the concept of connecting both source and drain to the output transformer, even though i cant realy explain why. Maybe its just cool.
However its a fun expirement and im rewinding a transformer at the moment to try it out.
Anyone having any thoughts or ideas are very welcome to tell me about them.
Most of this is unknown to me so Im in desperate need of information about the circuits and possible variations, pros and cons and so forth.

Johannes with fever and a bad cough.
__________________
We live in a horizontal world, why use vertical topologies???
  Reply With Quote
Old 26th May 2005, 08:58 AM   #9
AJT is offline AJT  Philippines
diyAudio Moderator
 
AJT's Avatar
 
Join Date: May 2003
Location: Palatiw, Pasig City
Quote:
The exact same reason im building amps in the first place: Its fun!
a valid reason i aggree, not that i need to. diy is all about fun!
btw, i made a desgn for output traffo for the tube mc270 amp for a friend but he insists to =see the original data, can you help? thanks
  Reply With Quote
Old 26th May 2005, 10:54 AM   #10
diyAudio Member
 
Join Date: Sep 2004
Location: Göteborg
The info I have is in Ir.Menno van der Veens book, Modern highend valve amplifiers.
A very nice book by the way.

What does "btw" mean?
Johannes.
__________________
We live in a horizontal world, why use vertical topologies???
  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
opamps used for unity gain HiFiNutNut Solid State 25 12th April 2011 02:34 PM
Heretical Unity Gain line stage PLUS a little gain ? yagas Tubes / Valves 7 24th January 2006 01:30 PM
Unity Gain (AV=1) Zen Amp LS Pass Labs 2 16th September 2004 04:40 AM
Unity Gain Operation (or low gain) Tomo Chip Amps 12 22nd January 2004 01:47 AM


New To Site? Need Help?

All times are GMT. The time now is 12:04 PM.


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