diyAB Amp - The "Honey Badger"

I'm good J, turned out the board fuses were blown, they were only 2A fuses, I forgot when I built it was all i had and meant to change them, but never did. When I cranked it to 11 last night it was just too much for them.

We don't want slow blow in there though right, we want them to blow fast to save stuff right?

JT
 
Hey AS, nope no lights on either board...

doublecheck the fuses. there is just the fuses and R53/R54 (if installed) and R32/R33 that is between power conections and LED's. So i doubt that the amp boards are getting any voltage. Outputs are also turned off. Thats why the PSU LED's stay lit.

EDIT: i see it worked out :) I use 4A slow blow in mine.
 
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As the other guys have said use T4A or T5A.
A F4A or F5A could nuisance blow given enough on/off cycles.
When I was busy building my linear lab psu which only had a modest 6300uF x2 per rail, i could literally see the 4A fast blow fuse wire in the fuse bend and curl (without breaking) at power on. But that would not last a long time

Those are the fuses from transformer to bridge and main filter caps. My amp boards have on board fuses as well, here I use fast blow fuses.
 
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Ya, that's the fuse/s to which i was referring. My thought was that you wanted something fast on the board to protect the devices, but slow on the main to help with the main cap charge.



I upgraded/rated almost all the parts I thought would be at risk for higher rail and lower impedance. I know I hit the 4-6Ohm Tekton DIs with well over 100W last night. The speakers were starting to making the windows breath. I didn't check the db, but it was over 100 for sure.


I don't listen at those levels, but every now and then there a beat or a riff I want to let my neighborhood hear. :)
 
Hmm

I had just 2Amp in there and it feel like they went when they should have. I know the speakers can handle a great deal, but it was not getting better just louder and not in a way that makes me want to go there.

I think I'll go back in and go up to 3 amp slow and call it good... if I cook them, it probably had to do with a good single malt. :p
 
the fuses should only break when there is a problem. It's not a general overload protection.
They realy do there job if D4/D5 fails and conducts. i learned that the hard way :) did the mistake and used 40V devices instead of 400V that i "read".
In that case the fuses saved all outputs in a all out short.
 
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The fuses are really protecting the wiring and power supply. By rights they should be located at the power supply (the source) not at the amp board as the new version looks like it will be. Anything to do with analog supplies has a large margin for error so slow blow is preferred normally. Fuse rating should match the output current of the transformer, in you case that's 5.5 amps, so a 6A fuse would be fine.