F5 Turbo Builders Thread

hello. just got a great idè regarding P3 trimmer for this amp, and all other F5's for hat matter.
how about a multi turn panel mount pot, connected to a digital ohm meter with a smal display on the front? that way you can easely get 2 monoblocks adjusted the same.
and for a stereo amp, one gan use a stereo pot with one ohm meter and display.
what do you think? and do anyone know who can be selling ohm meteres that can be used(that you can calibrate yourself)?

I think some output offset adjustment is necessary as now what is sent to output bias mech has changed. Perhaps a servo of some sort integrated into the idea may make it possible, dunno that much about them.
 
aah crap. hmmm. next isue. how much offset are we talking about?
i do want some easy adjustment on P3 without opening the amps.
so it can be adjusted after ones mood and music choice:)
maybe a mix of fixed resistor and pot. say a 50ohm pot and 2 75ohm resistors.
then you have a little adjustment without that much change in offset.
 
Hi AudioSan,
Set it up and try it ,If you want a ohm meter any DVM you could sacrifice the display and all of them have a calibration adjustment inside,I guess price would dictate how many digits you wanted,
You could use a vertical trim pot and a plastic adjust tool to get it to the front panel ,one of those with the hex hole would be perfect,
Good Luck to ya!
NS
 
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hi NS. i want a back light display that looks nice:) so a DMM is no no:)
i think i have to try some. hmmm. actualy. i can just try it on the F5 i have.
so that all s ready when the turbo monoblocks are build.
i also want to change one thing on the turbo. R5 and R6 says 1K. here i will go for 2.2K as the standar F5. so i dont run out of pot adjustment:)
parts will be ordered from mouser next week:)
 
Ill check, although i think any change that would cause a difference in sound would cause offset. What is acceptable, you tell me. WIth BA3 FE, you can get away with it because of cap.

that sounds great:) well. +/-50mV is acceptable.
so i guess there is some adjustments allowed:)
if one find the sweet spot on P3 and adjust offset to 0mV, there will be a little bit to go on i hope:)
 
here is a cat that has stamped in ink and running over paint trying to describe what i ment:D
 

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if this works. then maybe one will do with a single turn pot(50ohm)
and don't need display and ohm meter:)
and ofcourse. one can have a switch inside the amp, to switch between multiple resistor settings. and adjust offset from there. f.ex if you switch speakers or something else:)
and use the pot to adjust after type of music:)
 
I am going to show the monblock setup i have been talking about tomorrow. It is not ideal due to the unflat back of the 10.08 HS i got from HS USA. They are currently retooling to with a focus on a nice smooth and flat back for instances just like this. It is the reason they have been out of production for a while. Mine will work, but it puts the heatsink back on an uneven plane and will show up when the lid and bottom are added. It should still show a method that would allow the use of TeaBags boards, ChipAmp PSU, and possibly trado in single monoblock. I know this will open things up for some folks in building the larger versions.