BrownBox

GGJaguar

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Anyone using one of these with their vintage amps? In my current location, the wall voltage is 120-121, but at my other place it's more like 124-125. I just got one and, so far, have only used it with a couple of cathode biased amps. No discernible change in sound or feel, which is good, but now I have peace-of-mind that the amps' transformers, power sections and filaments aren't being stressed from over-voltage. I will have to check the bias of my fixed bias amps with the dropped voltage, but that's for another day(s).

BrownBox.jpg
 

Default

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You can look for "bucking transformer". If you have an amp guy, he can make one for you easily enough. Plans are on the web. I have the parts, but not the time.
 

Steve Messenger

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I've got one for my Homestead BF25 ... not vintage, but better safe than sorry
 

GAD

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No, but I do have one of these:

1593280261449.png


Not really for gigging, though since it probably weighs 80 pounds.
 

GAD

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'cause I know you freaks want to see inside. :)



 

AcornHouse

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I got this for working on them, since I measured my house voltage at 124. (And @Default , you have a unit already, but your poor addled mind seems to be gone. Ah well, we remember him well.)

5E5D0001-9E67-48E5-8AA8-4ED96B3B4530.jpeg
 

Default

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Oh, gone it is!

But, I digress. I have the parts to make a portable bucking transformer, for when I can get out to do open mics again.
 

GAD

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I got this for working on them, since I measured my house voltage at 124. (And @Default , you have a unit already, but your poor addled mind seems to be gone. Ah well, we remember him well.)

View attachment 3601
that’s the model I was about to buy when my behemoth showed up on ebay.
 

Quantum Strummer

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I have an old Eico Variac that I use with certain amps, a Fender Deluxe in particular. The wall voltage in my house is a pretty steady 122…I set the Variac to roll it down to ~115.

-Dave-
 

DThomasC

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I have a pile of variacs. Wire one of these up to one of them. Works great on the bench. Could travel with it I suppose...
 

Jeff Haddad

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I use one of these at home:
tone preserver.jpg


tone preserver
MIne is an older unit and it doesn't have the amps, just voltage. I think it basically does the same thing as the Brown Box.

My wall voltage is usually between 121 -125 and it seems like my old Fender amps prefer the 117 they were designed for (less -110 - on older amps). The difference is slight, but I felt that a Bandmaster Reverb (in a Super Reverb-style cab) sounded harsher at wall voltage compared to dropping 6 volts to 117 which seemed to sweeten it, or smooth it out a bit. Admittedly it could be I was "hearing with my eyes" since I knew I had lowered the supply voltage but I think I heard a subtle difference.

I use the tone preserver with all my amps from the '70's and older. During the summer with all the air conditioners running it's not necessary since the wall voltage is lower.
 
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