F6 Amplifier

F6CC compensation caps increased to 6.8nF from 4.7nF and the sound is very nice.

I have not run new square wave response tests, but here are earlier results. Input is a 50kHz square wave at 5us/div horiz, 1v/div vertical. From left to right:

  • no caps
  • 4.7nF caps
  • 10nF caps
With 10nF caps, the high end was noticeably flat. With 4.7nF maybe a little too sharp. At 6.8 it sounds very nice.

I think this amp will be a keeper.:happy1:
 

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@ZM,
I am following through simply because my time with Funny says its worth it. I hope to cut test box for Altec this week. With them up and running, perhaps balanced wll not interest me either, but only time knows the story:D. Glad to see they let you back in . Price $58. DOnt know if thats both or each. Either way, well worth it for custom product made to order, IMO, especially if it matches dual transformer performance. Seems like someone said it would. I am still liking that i can maintain a higher 2K:scratch:
@Ilquam,
Looks like you are on the right track to me. Dont trust the scope, you got two better ones attached to your head:D
 
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Official Court Jester
Joined 2003
Paid Member
@ZM,
I am following through simply because my time with Funny says its worth it. ......


not disputing that , quite contrary ...... ;)

however , that was sort of tough decision - staying deliberately in SE/non bridged(/balanced) territory ......... or going in that so seductive direction .....

strictly speaking of personal needs ; when going balanced , I'm automatically in higher power grade then I really need , using any of my FR or coaxes
 
Official Court Jester
Joined 2003
Paid Member
naah

I'm cheapskate ; bought mine K3809 for 350E/pair , with Manu's help in transaction and shipping (moi still behind iron semi-curtain)

however , when speaking Tanns - ceramic magnet and cloth surround types are safe bet , if further investment is to avoid (even if I still didn't heard of Tann AlNiCo go puff , I strongly despise their Tannoplas surrounds) .....

so - anything from K3808/9 and newer ;
 
Some progress...

attachment.php


Waiting for the chassis base now to hold the heatsinks so that I can solder the IRFs and start some tests...

The channel board will be on top of the psu filter with enough air to allow cooling of the electrolytics.

The trafo and the rectifier will be on a separate chassis.
 

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Some progress...

attachment.php


Waiting for the chassis base now to hold the heatsinks so that I can solder the IRFs and start some tests...

The channel board will be on top of the psu filter with enough air to allow cooling of the electrolytics.

The trafo and the rectifier will be on a separate chassis.
A lot of progress. Is your amp diyF6 with IRF's instead of R100A? Is it fair to say that using a separate chassis [another box] for the trafo and rectifier was inspired by the 2-chassis Xs amp{s} of Mr. Pass?
Best regards.
 
Yep IRFs for me

About the XS, not really. I never liked the idea of power transformers near high gain stages or signal transformers... Near anything to be honest :)

My phonoclone and my shigaclone both have an external psu, and my turntable and DCB1 are getting one very soon as well.

Of course seeing and reading about the XS line reinforced my decision :)
My psu case will be quite different though
 
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