AKSA 55, 100 - Listening impressions - Page 38 - diyAudio
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 2nd July 2009, 10:58 AM   #371
PMA is offline PMA  Europe
diyAudio Member
 
PMA's Avatar
 
Join Date: Apr 2002
Location: Prague
Something like this,Hugh?
Attached Images
File Type: png decay.png (42.4 KB, 594 views)
  Reply With Quote
Old 2nd July 2009, 11:17 AM   #372
AKSA is offline AKSA  Australia
diyAudio Member
 
Join Date: Sep 2001
Location: Melbourne, Australia
Precisely, Pavel.

Revealed to me now in sims, at last, I have something to hang my hat upon.

Hugh
__________________
Aspen Amplifiers P/L (Australia)
www.aksaonline.com
  Reply With Quote
Old 2nd July 2009, 12:53 PM   #373
Bigun is offline Bigun  Canada
diyAudio Member
 
Bigun's Avatar
 
Join Date: Jan 2009
Blog Entries: 2
And,

the harmonic profile has some dependency on signal amplitude and on frequency, another property of tubes I believe. All in all, done very nicely, the hallmark of a great amp.
__________________
"The test of the machine is the satisfaction it gives you. There isn't any other test. If the machine produces tranquility it's right. If it disturbs you it's wrong until either the machine or your mind is changed." Robert M Pirsig.
  Reply With Quote
Old 27th July 2009, 03:07 PM   #374
diyAudio Member
 
thoglette's Avatar
 
Join Date: Dec 2008
Default Happy engines

Quote:
Originally posted by AKSA
Yes, and the fact it engages.....

However, the story has a happy ending and that is the main thing.

Cheers,

Hugh
I also note (having watched from the sidelines since the beginning) that the AKSAs seem to make it into the secondary market very, very rarely.

IE the customers are happy with the ending. And that is the main thing.
  Reply With Quote
Old 3rd December 2010, 12:41 AM   #375
humble is offline humble  United Kingdom
diyAudio Member
 
Join Date: May 2007
Default aksa 55 etc

Quote:
Originally Posted by still4given View Post
Hi Forr,

With all due respect, the thread topic asks for "Listening impressions" For some reason I get the impression that you have not listened to one. Do you have something against Hugh?

Please, let's not muddy the waters. Many of us are curious how this amp actually sounds in comparison to some of the other popular DIY amps.

Blessings, Terry
Sorry to butt in, still forgiven!!
Just because an amplifier cct does not have a CC or Current mirror, does not invalidate its performance..Consider this scenario, even if you match very closely a differential I/P pair you will still have a common mode difference
which in the typical diff pair is complicated because it is across two different
transistors and the assumption is that what is fed back via the feedback loop
is identical to what is fed into its I/P but for the phase difference, unfortunately because the loudspeaker produces an impedance variation,
which in turn is also fed back to the diff pair albeit in reduced amplitude,
it is assumed that this is all somehow balanced out alas this is not quite true
because the impedance plot of the loudspeaker represents a changing phase
which is fed to the feedback side of the diff pair, now the diff pair has to cope with this factor plus the common mode errors, now in the Bailey cct
the I/P and the feedback is applied to a single transistor, so there is no common mode error, the control is also instant being in the same electron stream and this may account for some of the perceived accuracy of this topography, Dr Bailey who also designed the Bailey line transmission line back in the 60's, originally conceived this amp as a 30watt job using rather slow transistors by todays standards but after resolving a bad case of early effect in the main driver transistor was eventually able to produce a square wave at 50khz with little error he was using an RCA 40362 in the driver transistor for low cob and small early effect.. Of course there are better devices today..You can have a good amp with a CCS and current mirror if you remember to design for very high damping factors as this will reduce the
amount of loudspeaker impedance variations getting back into the feedback loop.Meridian did much work on this reflected impedance over 25 years ago
to deal with this type of problem..Its all well known..and it may be why some people like amps with no overall neg feedback..its all about proper design..Also J.Linsley Hood's class A amps of 15watts to 30watts also used a single I/P transistor and it was well thought of for its clarity..
In its day the Bailey amp was highly regarded although it was a class B,
despite which its distortion at full power and throughout the freq range was well under 0.1% regards
Humble
  Reply With Quote
Old 3rd December 2010, 01:35 AM   #376
diyAudio Member
 
ostripper's Avatar
 
Join Date: May 2008
Location: Albany , NY (smallbany)
Quote:
Originally Posted by PMA View Post
Something like this,Hugh?
Or like this... This topology can go ALL the way.
OS
Attached Images
File Type: gif bx2.gif (16.7 KB, 201 views)
__________________
Mongrel website , always current and updated :
http://www.fidelityforce.com/ostripper
  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



New To Site? Need Help?

All times are GMT. The time now is 05:24 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