Current feedback a la Mark Alexander+QRV06 = QRV03

[peranders]

http://www5.head-fi.org/forums/showthread.php?s=&threadid=35074

My Alexander headphone amp is slowly coming into life.

The basic concept is the Alexander amp and then I have added my QRV-06 amp as current amplifier.

http://www.analog.com/UploadedFiles/Application_Notes/492001115525484056221917334AN211.pdf

Please note that this design is protected by patent which means that my pcb's are not allowed to be used in commercial products, only for personal use. If anyone wonders I have got permission from Analog Devices.


If Christer or someone else would simulate it, I would be very greatful.

An externally hosted image should be here but it was not working when we last tested it.

 

[sonnya]

Why not take the full step and make a poweramplifier for speakers instead of headphones... Using QRV06? 😀 Just remember to check PSRR (hint)

 

[peranders]

I have thought about making an Power Alexander Amp, but at the moment my Gainclone will to do. I have limited resources, both in time and money so a real good power amp project have to wait.

 

[jan.didden]

http://www5.head-fi.org/forums/showthread.php?s=&threadid=35074[snip]Please note that this design is protected by patent which means that my pcb's are not allowed to be used in commercial products, only for personal use. If anyone wonders I have got permission from Analog Devices.[snip]

US Patent 5,097,223

Jan Didden

 

[peranders]

Anyone who is interested should also read the very original article published at Audio Engineering Society. Can be download for a small fee from AES.

 

[km]

hi.

indeed a good amplifier.

see; http://www.analog.com/UploadedFiles/Application_Notes/492001115525484056221917334AN211.pdf

rgds karsten madsen - www.cadaudio.dk

 

[peranders]

A better scanned AN-211 can be found here:
http://www.diymania.net/pass/project/pic/CF/2646.pdf

Have you seen this?
http://www.diymania.net/pass/project/CF-Power.htm

 

[peranders]

I have tweaked the amp a bit and now it works

It produces a very good sound, both with OPA134 and LT1115. 😀

Sonny, the thing I asked about was just a wild idea which wasn't too good This "idea" is now removed and the problems are gone.

I suggest that more test the current feedback becuase it's an interesting feedback technology. So many JLH fans couldn't be wrong.