Reducing B+ BrownBox

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amprx1
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Reducing B+ BrownBox

Post by amprx1 »

Does anyone have experience with lowering their B+ with a BrownBox?
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Pat Geraghty
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Phil_S
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Re: Reducing B+ BrownBox

Post by Phil_S »

Looks like a variac to me.
vibratoking
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Re: Reducing B+ BrownBox

Post by vibratoking »

As far as I can tell, it's a variac with the ability to increase voltage removed as a safety feature. The digital voltage and current readouts are nice to have, but some standard variacs have that as well. It has no regulation, which is a drawback if you want any substantial immunity from the variation of wall voltage. It's little more than a slightly altered variac.
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crbowman
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Re: Reducing B+ BrownBox

Post by crbowman »

I always thought the gateway to great tone was in your fingers.
Boy have I been doing wrong!!
<i> "I've suffered for my music. Now it's your turn."</i>
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crbowman
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Re: Reducing B+ BrownBox

Post by crbowman »

I always thought the gateway to great tone was in your fingers.
Boy have I been doing wrong!!
<i> "I've suffered for my music. Now it's your turn."</i>
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crbowman
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Re: Reducing B+ BrownBox

Post by crbowman »

I always thought the gateway to great tone was in your fingers.
Boy have I been doing wrong!!
<i> "I've suffered for my music. Now it's your turn."</i>
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martin manning
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Re: Reducing B+ BrownBox

Post by martin manning »

crbowman wrote:I always thought the gateway to great tone was in your fingers.
Boy have I been doing wrong!!
This bears repeating!
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Colossal
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Re: Reducing B+ BrownBox

Post by Colossal »

martin manning wrote:
crbowman wrote:I always thought the gateway to great tone was in your fingers.
Boy have I been doing wrong!!
This bears repeating!
This bears repeating!
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Masco
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Re: Reducing B+ BrownBox

Post by Masco »

Save yourself $300+ and build one of these:

http://www.geofex.com/article_folders/v ... ntvolt.htm
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NickC
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Re: Reducing B+ BrownBox

Post by NickC »

Colossal wrote:
martin manning wrote:
crbowman wrote:I always thought the gateway to great tone was in your fingers.
Boy have I been doing wrong!!
This bears repeating!
This bears repeating!
At the risk of being repetitive and redundant, I concur.
pops
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Re: Reducing B+ BrownBox

Post by pops »

A large choke before the first filter cap will lower your B+, it has to be able to handle the current of all the tubes tho not just the preamp. Dave Funk talks about doing this in his book, and i have used this technique in at least an amp or two.
The world is a better place just for your smile.
amprx1
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Re: Reducing B+ BrownBox

Post by amprx1 »

Thanks for the input.
Pat Geraghty
ampdoc1
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0ut of the box

Post by ampdoc1 »

I assume you are wanting to be able to use the variac to lower the power of the amp.

I wanted the same thing years ago, and tried the variac solution. I didn't like the extra weight, nor the fact that as all the voltages thru out the amp changed, and so did the sound and response.

Try a VVR with a 6VDC power supply to only the output tube heaters. Nothing is changed in the amp electronically or sonically, until the last stage, where the power tubes are not attracting as many electrons.
The only downside, also common to usual VVR uses, is that it takes a few seconds for changes in volume to settle.

Easy, works well!

a'doc
amprx1
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Re: Reducing B+ BrownBox

Post by amprx1 »

great Thanks
Pat Geraghty
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