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Hoffman Amps Forum image Author Topic: hammond 125J question  (Read 2637 times)

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Offline jackplug1

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hammond 125J question
« on: January 25, 2022, 09:37:18 am »
What output tubes would suit a Hammond 125J in push pull? 8watt, primary is 4k or 2.5k

Offline uki

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Re: hammond 125J question
« Reply #1 on: January 25, 2022, 04:55:40 pm »
Theory is when everyone knows everything but nothing works, practice is when stuff works but nobody knows why !!!
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Offline jackplug1

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Re: hammond 125J question
« Reply #2 on: January 27, 2022, 08:25:50 am »
I was thinking of something similar to a 12c5 but with 6.3v filament but I have not yet found a tube with low output and a plate resistance suitable for the 125J

Offline PRR

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Re: hammond 125J question
« Reply #3 on: January 27, 2022, 01:10:24 pm »
Push-pull 25L6 at 190V.

This OT is NOT good for most projects. Do you already have it in hand?

Offline jackplug1

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Re: hammond 125J question
« Reply #4 on: January 28, 2022, 11:49:08 am »
"This OT is NOT good for most projects. Do you already have it in hand?"

As I suspected. I bought this for use in a SE amplifier, its now temporarily in a fender 6G15 reverb project,  but it is a bit big for that and I have found a smaller transformer which will do. I just thought I could put the 125j to good use. I might just as well leave it where it is as it seems to work ok in the reverb.

Offline thetragichero

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Re: hammond 125J question
« Reply #5 on: January 30, 2022, 10:28:53 pm »
hmmm are the leads still relatively long and are you in the us? i have a (currently sidelined due to packing and moving) reel-to-reel amp conversion project using 25l6 i was just going to use an 18w hammond ot in that this would be suited for (the plan is for an older, 50s amp type sound so the 18w transformer would possibly be too hifi and certainly larger than needed). maybe we could trade?

Offline jackplug1

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Re: hammond 125J question
« Reply #6 on: March 05, 2022, 08:05:34 am »
hmmm are the leads still relatively long and are you in the us? i have a (currently sidelined due to packing and moving) reel-to-reel amp conversion project using 25l6 i was just going to use an 18w hammond ot in that this would be suited for (the plan is for an older, 50s amp type sound so the 18w transformer would possibly be too hifi and certainly larger than needed). maybe we could trade?

Sorry - in the UK

 


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