DCAudioDIY.com

DC Area Audio DIYer's Community
It is currently March 28th, 2024, 2:28 pm

All times are UTC - 5 hours [ DST ]




Post new topic Reply to topic  [ 4 posts ] 
Author Message
 Post subject: Output impedance
PostPosted: April 10th, 2017, 10:56 pm 
Offline

Joined: October 10th, 2016, 10:23 pm
Posts: 55
Hi,
What can I expect by putting 5.6K output trannys in a push-pull ultralinear system designed for 4.3K trannys?
I presume coupling cap sizes may need to be reevaluated.
Long story: I was going to build a new "Dynaco ST-70" based on a new driver and the Dynaco iron I had. After moving back to DC, I can no longer locate my project parts, so on an impulse, I bought a pair of Sophia Electric 5.6K p-p output trannys (who knows, probably from someone in this group). So now I may be potentially building a Dynaco amp with no Dynaco parts or topology.
Anyhow, I am hitting the books again, but am curious as to what issues I may encounter if I tried a direct drop-in of the Sophia parts to a design for a different hunk of iron.


Top
 Profile  
 
 Post subject: Re: Output impedance
PostPosted: April 11th, 2017, 11:28 am 
Offline
Site Admin
User avatar

Joined: February 28th, 2013, 10:38 am
Posts: 1682
It shouldn't be a problem. You may get slightly less power output than you were expecting. If you're really worried about it, get some 6ohm speakers and run them on the 8ohm tap ;)

Roscoe

_________________
I can explain it to you, but I can’t understand it for you.


Top
 Profile  
 
 Post subject: Re: Output impedance
PostPosted: April 11th, 2017, 12:50 pm 
Offline
User avatar

Joined: July 24th, 2015, 4:17 pm
Posts: 1701
Location: Parkville, Maryland
Looking at the EL-34 datasheet -- the EL-34s just may like the replacement transformers. Or -- you can try KT-88s and get more dynamic bang for your buck.

_________________
Walt


Top
 Profile  
 
 Post subject: Re: Output impedance
PostPosted: April 12th, 2017, 7:41 pm 
Offline

Joined: April 22nd, 2013, 12:58 pm
Posts: 285
Just like in triode mode, distortion tends to go down as primary impedance goes up. IIIRC, you don't lose as much power output as you do in pentode mode as you move away from the optimum power transfer point.


Top
 Profile  
 
Display posts from previous:  Sort by  
Post new topic Reply to topic  [ 4 posts ] 

All times are UTC - 5 hours [ DST ]


Who is online

Users browsing this forum: Google [Bot] and 48 guests


You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot post attachments in this forum

Search for:
Jump to:  
cron
Powered by phpBB® Forum Software © phpBB Group