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Hoffman Amps Forum image Author Topic: Dual 50 build  (Read 1696 times)

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Offline Bieworm

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Dual 50 build
« on: October 28, 2024, 02:41:42 am »
Hey guys

I built another Dual 50.  But I immediately adapted the changes I made last time which suit my taste better.

- cathode cap on V1a is 4.7uf instead of the 330uf (plexi bass)
- coupling cap on V1a is .01uf instead of .022uf (plexi bass)
- cold clipper is 7.7k instead of 10k
- deleted bright cap on V1b (plexi bright)

it's a matter of personal preference but these tweaks remove a lot of the sub harmonics I seem to dislike
"This should be played at high volume.. preferably in a residential area"

Offline Big_Mike

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Re: Dual 50 build
« Reply #1 on: October 28, 2024, 09:16:53 pm »
I am looking to build a Dual 50 myself and was wondering where you purchased the chassis.  Finding a plexi chassis with 4 preamp valves is almost impossible looking around the web.  Also, do you have a recommendation on sourcing the transformers?  Thanks!

Offline Bieworm

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Re: Dual 50 build
« Reply #2 on: October 29, 2024, 01:08:00 am »
I am looking to build a Dual 50 myself and was wondering where you purchased the chassis.  Finding a plexi chassis with 4 preamp valves is almost impossible looking around the web.  Also, do you have a recommendation on sourcing the transformers?  Thanks!
I buy blank chassis’ from TubeTown Germany. This one was 430x170x60mm.
The transformers are spurced there too. Tubes I buy at Jukeboxrevival.eu. I use 6N2P preamp tubes
"This should be played at high volume.. preferably in a residential area"

 


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