I'm going to make the double bias mod to my hiwatt using a couple of 25k locking shaft pots like this one. http://www.mouser.es/ProductDetail/ETI- ... 52btESU%3d . I was thinking on locating the pots up on the chassis, just using the 2 remaining holes between preamp tubes, and using some sort of bias probe I won't have to deal with all of those potencially killer cables down there...
[img505]http://www.amparchives.com/Amp%20Archiv ... nside1.jpg[/img]
I see some things on the way: the rolled pair of cables and that big silver cap, but it seems like achievable.
Does anyone performed something like this? Or does anyone have any other useful/"elegant" suggestion/alternative example?
Thanks in advance, Gilberto.
Dr-103 Double-bias-mod chassis pots locations
Moderators: pompeiisneaks, Colossal
-
- Posts: 4609
- Joined: Fri Jan 24, 2014 3:01 pm
- Location: 1/3rd the way out one of the arms of the Milkyway.
Re: Dr-103 Double-bias-mod chassis pots locations
Have you un bused the amps grounds? The stock wiring is neat as a pin, but does not make for least amount of 120 hz hum you can end up with !
When I die, I want to go like my Grandfather did, peacefully in his sleep.
Not screaming like the passengers in his car!
Cutting out a man's tongue does not mean he’s a liar, but it does show that you fear the truth he might speak about you!
Not screaming like the passengers in his car!
Cutting out a man's tongue does not mean he’s a liar, but it does show that you fear the truth he might speak about you!
Re: Dr-103 Double-bias-mod chassis pots locations
Yeah, that´s what I thought... Maybe attaching a trimmer to a sort of board material piece, drilling holes on the sides for having screws attached to the chassis holes, leaving the trimmer accesible throught the free preamp hole...Stevem wrote:Have you un bused the amps grounds? The stock wiring is neat as a pin, but does not make for least amount of 120 hz hum you can end up with !
Or is just how close would be the cables from the pot the main problem?
The attached files show a dr-504 work where I took the idea from.
Cheers, gilberto.
You do not have the required permissions to view the files attached to this post.