F6 Illustrated Build Guide

sov

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Joined 2016
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It was very fun testing Pico's magic F6. I spent a whole day listening at different levels.
With my sensitive speakers my ears got tired, especially at moderate levels and above. Plain F6, or with LEDs, is more gentle. For users with less sensitive speaker or another approach in lisstening I think this is rewarding. Me, I'm going back to almost plain.

Pico's Magic F6 Trick

Thank you Pico for pushing boundaries :)
 
Just a query, will the IXTH60N20L2 do the job instead of the 64n10 - apparently, Mouser hold 22 of the 60N20 - saves an order to Digikey (stock of 25) for the 65n10s - do they still has the minimum order surcharge?

RS are holding the Vishay IRFP250 in packets of 5 here.

It seems like 60N20L2 would work glancing at the datasheest but Ciss is 10,000pF, which is essentially three times higher than 64N10L2. So I wouldn't recommend it.

Try and stay with 64N10L2
If you spend $60 AUD you get free shipping from digikey.
 
I haven't come across these ones before, tamra but the specs show they're made of the Manganin material - seems a bit cheap but "worth a punt" - they're just rated 1w but maybe can attach a heatsink to keep them cool.

I don't think the Vishay LVR range will have the resistance like 100R, maybe just 1R0 - and made of Nickel-Chrome, not Manganin - a quite different sound.

Thanks 'pico' for the info about the fets - will add to a large order list from the US.
 
I just finished my F6 amp. One channel behave as it should – I easily adjusted BIAS to 0.5V across the 0.47Ohm resistor and OFFSET to 0V DC across the speaker terminals.
I have a trouble with second channel – BIAS volage is from 0 to 0.01V, MOSFETS are not warm at all (as they are off). JFETS are warm when I touch them, around 40 degrees Celsius.
Kindly suggest what can be reason of such a strange behavior.
All components are soldered as they should be. Picture of faulty boar are attached.
 

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