Opinions on Push-pull, class-A, transistor preamps

[JohnRoberts]

The circuit could surely be redesigned to be stable with modern parts. The original designer did what they could do with the components available to them at the time. There may be more improvements available in a modern design.

JR

 

[lassoharp]

I found an interesting old thread online from 2005 where John contributes and talks about the Altec 9475 design.
His first post:

"I designed the 9475. It is an updated Langevin AM-16. Has wider freq. resp and less distortion. Also same ckt. was put in special package for MA BELL to use in repeater units. Had octal base like vacuum tubes. This was in 63 when ALTEC had the AUDIO CONTROL DIV. Schematics same as AM-16, just better xfmrs. ALTEC's Peerless xfmr div would not make the xfmrs. The eng dept said that it would not work. A company in Santa Ana , ROBOT COIL built them."


The rest here:
http://www.3daudioinc.com/3db/showthread.php?53-Altec-9475a-

Have you tried to access the 3dbaudionic forum lately? I was getting it fine for a while but cannot reach it now (non responsive server) I get the same error message when I click on the link you provided

 

[cyrano]

Have you tried to access the 3dbaudionic forum lately?

Typo?

The link in Winston's post works for me.

 

[lassoharp]

Typo?

The link in Winston's post works for me.

This is all I get when trying his link

 

[cyrano]

No typo there. What's your DNS set to?

Try setting to 8.8.8.8 and 8.8.4.4 (Google DNS) as a test.