I am currently building a Mofo to drive an efficient 100db 8ohm speaker. In my estimation, one or two watts RMS should be enough to have comfy or even loud volumes. For now I am building it according to the article with a 12V smps and IRFP250 biased at 1.7A. Does it make sense to look for a smaller mosfet that would bias with a smaller current and a smaller heasink? Any suggestions for parts to try?
Thanks. Any suggestions for min voltage and bias currents for it?IRF510
I had a deep dive in my stash but could not find any 510s. I'll get some on my next order.
I got lots of 610s and FQP3N30s though, so I'll probably start there
I'll check the mini. Thanks again610 is good too
see Papa's ACA Mini for rails and Iq
say 15Vdc and no less than 200mA
more if you need more oomph!
2 Watts works out something less than 7V and 1A. A third of the heat. I don't think you need to down-size the FET for such a small shift. I don't know that the energy savings justifies odd power supplies; 12V seems fine to me. You rarely regret having a little more power thna you think you need. (And it is easy to mis-estimate.)100db 8ohm speaker. {snip} one or two watts RMS should be enough {snip} 12V smps and IRFP250 biased at 1.7A. Does it make sense to look for a smaller mosfet that would bias with a smaller current and a smaller heasink?
2 Watts works out something less than 7V and 1A. A third of the heat. I don't think you need to down-size the FET for such a small shift. I don't know that the energy savings justifies odd power supplies; 12V seems fine to me. You rarely regret having a little more power thna you think you need. (And it is easy to mis-estimate.)
there is some minimal DS voltage, to keep intrinsic mosfet capacitances at least somewhat linear
lower than that, that cap goes wild
tango made ones https://www.passdiy.com/project/articles/arch-nemesisI haven't read the whole thread yet (I will), but can anyone recommend a production output transformer that could replace the capacitor on the output? What would the specifications for it be?
Where are they located - no mention of this anywhere?J&K Audio Design can build output transformers for solid state amps. I have a pair which I will be using for a SIT amp.
They are in Malaysia. Their website is https://jandkaudiodesign.blogspot.com/.
What about a "balanced" Mofo? Yes, double everything, but no output cap...I haven't read the whole thread yet (I will), but can anyone recommend a production output transformer that could replace the capacitor on the output? What would the specifications for it be?
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