Tube amp schematics 101, etc: NEW NEWER UPDATE: Biasing tutorial!

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Re: Tube amp schematics 101, etc: NEWER UPDATE: 5F1 champ schematic walkthrough!

Post by Maggieo » Fri Aug 15, 2008 12:16 pm

So THAT's what a "soul" control is!

Who does that? Carr?
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Re: Tube amp schematics 101, etc: NEWER UPDATE: 5F1 champ schematic walkthrough!

Post by Jay » Fri Aug 15, 2008 2:13 pm

Allen does the "Raw" control but IIRC from reading elsewhere on the interwebz, it actually bypasses the entire tone-stack to increase overall gain (pretty dramatically) as opposed to affecting negative feedback in any way.  Pretty cool trick that works great in pedals too, especially the big muff.  :)

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Re: Tube amp schematics 101, etc: NEWER UPDATE: 5F1 champ schematic walkthrough!

Post by tribi9 » Fri Aug 15, 2008 9:19 pm

I haven't been here too long but I think  it's pretty cool what you do Brad.

Im sure there's lots of us that truly appreciate it! 

Cheers!
Last edited by tribi9 on Sun Aug 17, 2008 6:13 am, edited 1 time in total.
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Re: Tube amp schematics 101, etc: NEWER UPDATE: 5F1 champ schematic walkthrough!

Post by 1946dodge » Sat Aug 30, 2008 4:43 pm

Remember that this stuff is all according to my understanding, and I'm totally self-taught... no electrical engineer here, just a dorky amp guy... so I'm not responsible if there are gaps and possibly small accuracy quibbles.  I do try to only post stuff I know for sure, though.  Wink
Well I gotta tell ya, I am an electrical engineer and I am learning stuff from you (mostly long forgotten or never understood). You have just succeeded in waking up in me what I learned in the 60's when I went to school!
For that I thank you, my talented smart friend.

I am looking forward for anything you give us. It is the most lucid explanation I have seen in 40 years.

Thanks a million.
Last edited by 1946dodge on Sat Aug 30, 2008 5:55 pm, edited 1 time in total.
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Re: Tube amp schematics 101, etc: NEWER UPDATE: 5F1 champ schematic walkthrough!

Post by 1946dodge » Sat Aug 30, 2008 7:55 pm

Me too. I read all the time. I am thankful that you read books, simplify what you read and give it to the rest of us.
That is science and engineering at its best.
A  man studies and learns all of his  life, and  attains wisdom only when he finds that  he knows much and understands nothing.

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Re: Tube amp schematics 101, etc: NEWER UPDATE: 5F1 champ schematic walkthrough!

Post by Superfuzz » Sun Sep 07, 2008 2:44 am

This thread must go into the library section..never learned so much in a sunday morining.. :-*
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Re: Tube amp schematics 101, etc: NEWER UPDATE: 5F1 champ schematic walkthrough!

Post by 1946dodge » Sun Sep 07, 2008 5:38 am

I think putting it in the Library is a great idea. Then it won't be hard to find.
However, I see that ####### has already put it as a pretopic so it will stay in one place too.
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Re: Tube amp schematics 101, etc: NEW NEWER UPDATE: Biasing tutorial!

Post by noirengineer » Tue Sep 09, 2008 3:03 pm

your the man!  8)

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Re: Tube amp schematics 101, etc: NEW NEWER UPDATE: Biasing tutorial!

Post by Maggieo » Mon Sep 15, 2008 3:12 pm

Hey Brad, can you explain what's up with "matched pair" power tubes?  In, for example, a 6V6GT powered amp, do both power tubes have to be the same brand or what?  I was thinking about dropping some of the spare 6V6GTs I've got for my Vibro Champ into the AST, but I only have single examples of any given brand of tube.
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Re: Tube amp schematics 101, etc: NEW NEWER UPDATE: Biasing tutorial!

Post by Maggieo » Mon Sep 15, 2008 4:36 pm

Yep, the Swart is cathode-biased.

So, different 6V6GTs will draw different amounts of current?  Why is that?
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Re: Tube amp schematics 101, etc: NEW NEWER UPDATE: Biasing tutorial!

Post by Maggieo » Mon Sep 15, 2008 8:28 pm

Wow!

I guess I'd better go looking for some NOS matched pairs to play with the Swart.

The Vibro Champ is cathode biased, too, right?
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Re: Tube amp schematics 101, etc: NEW NEWER UPDATE: Biasing tutorial!

Post by Maggieo » Mon Sep 15, 2008 8:54 pm

Thanks for the "used, test strong" tip, Brad!!!

I'll keep my eyes peeled.
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I am not an attorney and this post is for entertainment purposes only. Please consult a licensed attorney in your state for legal advice.

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Re: Tube amp schematics 101, etc: NEW NEWER UPDATE: Biasing tutorial!

Post by Regan » Fri Sep 19, 2008 4:45 am

Brad, all I can say is, "WOW"!!!!! Oh, yeah, and,  "THANKS"! I would say more but my brain is about to explode from all this information!!!


You 'da man!!!!!


Regan

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Re: Tube amp schematics 101, etc: NEWER UPDATE: 5F1 champ schematic walkthrough!

Post by luau » Mon Nov 03, 2008 9:17 am

øøøøøøø wrote:Here's the good news:  You can go to this page: http://www.webervst.com/tubes/calcbias.htm
Broken link. http://www.webervst.com/tubes1/calcbias.htm
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Re: Tube amp schematics 101, etc: NEW UPDATE: coupling capacitor summary.

Post by tribi9 » Sat Nov 08, 2008 1:40 am

I just spent like 3 hours re-reading this post. :ph34r:

Would anybody have some clear nice shots of the guts of a champ? Also a pic of a power transformer without the cap would be nice if anyone's got one?

:)
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