Here's my take on the F5 - it's my first step outside of a straight kit build so I kept it as vanilla as I could. It took me a while to distill all of the help and knowledge from this forum and Papa Pass' website.
Parts selection is suitably over-spec'd as I guess is expected for a novice without an EE background. The transformer is mounted on a galvanised steel timber brace, not how I planned to do it originally, but you gotta make the most of the space you've got.
DC offset is around 20mV at startup and sinks down to 1 or 2mV once things heat up - I feel pretty chuffed at that. Bias is as suggested in the original article at 1.3A.
I had a bit of auditable hum with the "old wiring" (first internal shot) but some tips from a nice chap in a chat room, a bit of twisting and re-routing and I'm down to a barely audible hum (second internal shot).
It sounds simply wonderful - super pleased with how things turned out - this site is an amazing resource - thanks to everyone that makes it what it is!
Parts selection is suitably over-spec'd as I guess is expected for a novice without an EE background. The transformer is mounted on a galvanised steel timber brace, not how I planned to do it originally, but you gotta make the most of the space you've got.
DC offset is around 20mV at startup and sinks down to 1 or 2mV once things heat up - I feel pretty chuffed at that. Bias is as suggested in the original article at 1.3A.
I had a bit of auditable hum with the "old wiring" (first internal shot) but some tips from a nice chap in a chat room, a bit of twisting and re-routing and I'm down to a barely audible hum (second internal shot).
It sounds simply wonderful - super pleased with how things turned out - this site is an amazing resource - thanks to everyone that makes it what it is!
Attachments
Last edited:
Super nice build! If it doesn't get too hot you can try .7V across the source resistors.
heya all, sorry if similar question has been asked before but 16k+ posts is really huge reading material..
ok, here is the question... will this heatsink be suitable for F5, dimensions are in pic (ofc I plan to use two of them, one for each channel).
tranny I plan to use is 2x17V 300VA, output devices IRFP's.
It will be hooked on B&W685 in cca.20m2 living room...
tnx
ok, here is the question... will this heatsink be suitable for F5, dimensions are in pic (ofc I plan to use two of them, one for each channel).
tranny I plan to use is 2x17V 300VA, output devices IRFP's.
It will be hooked on B&W685 in cca.20m2 living room...
tnx
Attachments
I am having 1 per channel of 300x40x165mm in a 4U case and it gets ~55-60 degree C hot. This: Dissipante 04/300N 4U 10mm NERO
Anything smaller is not enough. + don't forget to flat sand the cooler before attaching the transistors - it makes huge a difference.
Anything smaller is not enough. + don't forget to flat sand the cooler before attaching the transistors - it makes huge a difference.
Toner Layouts for F5
Hello,
There was a request for F5 Layouts in the Pictures Thread
Pictures of your diy Pass amplifier
I have some made for myself. I would post them here so Ballisticz4 and maybe other Members can use them well too.
But they are very inspired by the original F5 Layouts.
Is it a Problem? Or is this maybe not welcome?
Any recommendations / suggestions?
Hello,
There was a request for F5 Layouts in the Pictures Thread
Pictures of your diy Pass amplifier
I have some made for myself. I would post them here so Ballisticz4 and maybe other Members can use them well too.
But they are very inspired by the original F5 Layouts.
Is it a Problem? Or is this maybe not welcome?
Any recommendations / suggestions?
Thanks! I filed the holes smooth but you’re right - better safe than sorry - I’ll put an order in cheers!
add a heatsink to the jfets and increase bias far as you can, thus increasing power in class A