Found a complete LSK BAF kit so will get that built and cased when it arrives.
Still can't solve the hum, I have the IEC ground , PSU board ground and Transformer ground all going to a bolt on the perforated chassis inner. Do I need to connect it any other way to the chassis? The M2 boards are connected to the ground on the PSU board.
I've tried rotating the transformer to no effect, re-routed cables to be further away from each other and nothing makes any difference, no change in hum volume at all. Should I buy some Mu metal and cover the Edcor transformers?
Still can't solve the hum, I have the IEC ground , PSU board ground and Transformer ground all going to a bolt on the perforated chassis inner. Do I need to connect it any other way to the chassis? The M2 boards are connected to the ground on the PSU board.
I've tried rotating the transformer to no effect, re-routed cables to be further away from each other and nothing makes any difference, no change in hum volume at all. Should I buy some Mu metal and cover the Edcor transformers?
Shielded signal wire (sorry if already answered). It is what cured mine. It can still hum a bit if I move it too close to another piece of heat with a transformer in it as well, so they can be sensitive.
Thanks, from input to board and output? I'm using a good twin core with shield for input but twisted multistrand for output to speaker posts.
I was concerned with the output.
I also noted the other day a bit of hum, and the RCA Jack had just gotten a little lose, Pushed it in, no hum.
I have had the same issue, and have tried several earth methods to no avail
Just waiting for some MuMetal to arrive for covering the Edcor's
But I have also ordered a new set of JFets
Hopefully fixing the hum issue will be my Christmas present
With my M2, the whole thing goes in a deluxe 4U box. Shielded wire on the inputs, no shields on any transformers. Construction for power supplies and grounds are just as 6L6 did on the F6 amp build article. 2 CL-60 on the soft start, one CL-60 from power supply to ground. Amp is very quiet, even with 98dB and 100+dB speakers.
Are these hum problems possibly RFI, or from a component upstream? I tried to find a hum that appeared on a F5 build, it just suddenly appeared while testing with a roku box streaming music. Turned out the hum was caused by the monitor I was using....when it unplugged, hum stopped. System worked fine with laptop doing the streaming.
Hums are funny things.
Russellc
Are these hum problems possibly RFI, or from a component upstream? I tried to find a hum that appeared on a F5 build, it just suddenly appeared while testing with a roku box streaming music. Turned out the hum was caused by the monitor I was using....when it unplugged, hum stopped. System worked fine with laptop doing the streaming.
Hums are funny things.
Russellc
A couple of pages back you will see a list of my endeavours Russell
I should also note that I have tried the M2 amp in another persons home as well and the hum is still there
And the hum is also present even if the RCA cables are not connected
I will get there in the end even if I have to purchase a seperate case for the power supply
FR
I've tried shielded cable, to no effect, removed the Toroidal transformer from the case (which reduced the hum by about 50%) so I'm not sure what to do next.
I've replaced the output wiring on one side here with shielded cable that has the shield attached at the binding post end only. If it had worked I would shorten it slightly along with the solid core input wiring.
I might switch the boards out for a set of Aleph 30 ones I have here and see if they are quiet. If they are I'll just listen for a few weeks and take a break from the M2 construction.
I've replaced the output wiring on one side here with shielded cable that has the shield attached at the binding post end only. If it had worked I would shorten it slightly along with the solid core input wiring.
An externally hosted image should be here but it was not working when we last tested it.
I might switch the boards out for a set of Aleph 30 ones I have here and see if they are quiet. If they are I'll just listen for a few weeks and take a break from the M2 construction.
Your psu transformer position are reverse ( not on front panel side ) and to close with audio inputs and speakers outputs.
Put filter psu caps pcb in this position, reverse amplifier circuits pcs's position as well so your Edcors
are in proximity of rca inputs and far from new psu toroid position.
Take example from photo of First Watt M2 amplifier who work like charm
Edcors are shielded by mu metal screen...enjoy sound from your new diy amplifier.
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