balancing act between drive , increasing xconductance of OS and it's rising capacitance
as Papa recently said - I just hook these things up and see what I get

in his case "see" is certainly longish process
go figure

for instance - in Babelfish J , I'm finding one pair of IRFP150N better than 2 pairs of IRFP240N ....... not just because matching is not necessary
as Papa recently said - I just hook these things up and see what I get

in his case "see" is certainly longish process
go figure

for instance - in Babelfish J , I'm finding one pair of IRFP150N better than 2 pairs of IRFP240N ....... not just because matching is not necessary
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Love the diode heatsinks...perfect for my solution.
Size of your main heatsink is ?
Looking forward to your findings driving that board really hard.🙂
These sinks are 6" x 16". THey will not be the final destination. I will have another set that are 8" x 15" for the final build. I will use larger heat spreader as well, increasing 3/8" x 4 x 12" to 1/2" x 6 x 12"
These sinks are 6" x 16". THey will not be the final destination. I will have another set that are 8" x 15" for the final build. I will use larger heat spreader as well, increasing 3/8" x 4 x 12" to 1/2" x 6 x 12"
here's mine...shorter box ( 300 mm ) but 11 cm of heatsink depth by 15 cm high
should make a really nice and compact build 🙂
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Gama aluminum....... unfortunately a bit far off for you, in Slovakia.
'course if it is too hot i have master ZM's Babysitter:🙂
'course if it is too hot i have master ZM's Babysitter:🙂
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I run them a little above half rated voltage... extremely silent.
All you really need is to get the air moving a little, makes a huge difference here in Lisbon summer 😀
All you really need is to get the air moving a little, makes a huge difference here in Lisbon summer 😀
Absolutely. I built a box with dual 120mm fans pulling across a single 10" x12" heatsink and was able to run 300w. It got hot in the room quickly.
Spreading audio porn all over tonight
Very cool buzz. Looking forward to seeing how those heatsinks work when you throw a couple more pairs on there. They look like the 10" profile sinks for heatsink USA, which I was thinking of using for my build.
If i go with 4 pairs, I will use a single 1R resistor and cut the bias in half. I don't need more power, so it is just a matter of whether or not I like 4pairs@400mA or 2pairs@800mA. IF I like the 4 pair, I may try 4 at higher bias as well, using monoblocks. The heatsinks are very similar to the HS USA 10", but not the same. I have the HS 10" waiting in the wings. BTW, I should be packing the kit stuff in the next week or so. Also. I should be listening to a standard vs upgraded version of the F5T tonight. Little comparison.
If i go with 4 pairs, I will use a single 1R resistor and cut the bias in half. I don't need more power....
This my exact situation, i'm very curious to hear your subjective experience about these two possible choices.
😎
I hope to measure the current two pair version this weekend and then do that as well for the 4 pair version. Too much subjectivity is trouble around here.
😀😀
I know , the subjectivity i refer to is the comparison between a cooler running class a amp and a hotter ( better sounding ? ) one as has been expressed in many post.
I'm guessing a 4 pair one should have a cleaner punchier bass...i might be wrong
My subjective reasoning is that current delivery to load should be quicker with 4 pair but that has to be possible also by the PSU.
????? let us know😀
I know , the subjectivity i refer to is the comparison between a cooler running class a amp and a hotter ( better sounding ? ) one as has been expressed in many post.
I'm guessing a 4 pair one should have a cleaner punchier bass...i might be wrong

My subjective reasoning is that current delivery to load should be quicker with 4 pair but that has to be possible also by the PSU.
????? let us know😀
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If i go with 4 pairs, I will use a single 1R resistor and cut the bias in half. I don't need more power, so it is just a matter of whether or not I like 4pairs@400mA or 2pairs@800mA. IF I like the 4 pair, I may try 4 at higher bias as well, using monoblocks. The heatsinks are very similar to the HS USA 10", but not the same. I have the HS 10" waiting in the wings. BTW, I should be packing the kit stuff in the next week or so. Also. I should be listening to a standard vs upgraded version of the F5T tonight. Little comparison.
Yes, welcome ....... 🙂 8cylinders beat 4 cylinders ... for smoothness and delivery all the time .............

I hope to measure the current two pair version this weekend and then do that as well for the 4 pair version. Too much subjectivity is trouble around here.
Pour it on , I gotcha back bro ..... 😀
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)?
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)?
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