F5 Headamp ?

Previously in post #195 & #196, we published Id vs Vgs curves for the IRF and FQP output devices.

There have been some discussions about comparing 2SK2013 / 2SJ313 vs FQP3N30 / FQP3P20 in this or other applications.
I thought it would be best to compare their Vgs vs Id directly.

The first is Vgs vs Id.
Red is Fairchild FQP3N30 and blue is Toshiba 2SK2013.
The Fairchild has a higher Vgs over the entire range of Id (to 300mA).

The 2nd is vgs vs Id around the bias point, so that the static bias voltage has been subtracted.
One can see that the Fairchild also has a higher transconductance.

The rest, such as capacitances, etc. are best referred to corresponding datasheets.


Patrick

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I can only second Patrick, Fred!

One day you will be tired from travelling, and then you want to sit down in your favourite recliner
and listen to some good music via your headphones and a really good headphone amp...

Taking this chance to post a few images of my finished F5HA (finished months ago, only added the decals...). Sounding superb!



Err, that one took longer than 3 days to build. :D


Simply stunning Oliver

easily among the most beatifull builds i have seen in this site ...or any other for that matter.

Tiroler is my ref here !

:D
 
Built my F5HA on vero board. Schematic included.
Power supply is +/-16V from diy Kubota regulator. mosfet drain resistor are two 6.8R parallel because I can't get 3.3R 1W from local shop lol.

I used K246 J103 with matched Idss of 3.21 for 1 channel and 3.27 for the other.

I have a question, is R_drain of jfet set right?
 

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