F5 Turbo Builders Thread

The 2sk1530 has lower Vgs for given current in comparisonto 2sj201. If youhad both pots set to 1.5V, you would have sythe sk1530 biased fairly high, while the 201 would just be just turning on. Takr a look at the datasheets for appx Vgs for a given current.
 
Odysseas - goal is to set them at desired current - measuring voltage across one of source resistors ;

that voltage is information about current flowing through resistor and mosfet itself



who cares what's Ugs ......


there are few tutorials floating around , and reading them few times is worthwhile
 
Yes, thanks ZM, looking at the differences at the datasheets of the two toshibas, I wonder what would that (desired) current is. I just want to be at all times class A.
There is quite some difference at the current drain at the same voltage, like buzz pointed out.
 
Yes, thanks ZM, looking at the differences at the datasheets of the two toshibas, I wonder what would that (desired) current is. I just want to be at all times class A.
There is quite some difference at the current drain at the same voltage, like buzz pointed out.

do what buzz buzzed few times to you , already ;

stay in ballpark for your project (didn't read which iteration you are exactly building) keeping in mind that (say) 40W per device and 55C at heatsink are limits which you must respect
 
I didnt realize how blurry it was. The blue is loopback showing soundcard distortion and the red is the distortion of the F5T at 1W. Its a breakdown of the harmonic structure of the distortion. Like I said, I am not 100% sure of its validity, but i think it is right. My ears seem to agree😀
 
Yes. It is very good from top to bottom. I cant say that it is my favorite, but that is yet to be decided. I have to bring forth proper competition. I did not like the F5, and hearing the F5T has sold me on the multiple output concept. Of course my system has to be considered.
 
I decided to check out my p/s so hooked up the transformer/rectifiers and caps which loaded with nothing more than 3k3 bleed resistors and a couple of led's is giving me +- 38V dc.What sort of voltage drop can I expect with a V2 amp?
The transformer is 350VA with 25-0-25 secondaries.
 
multiply your secondary times 1.3 for a good approximation. 38v is fine as long as you you the cascaded version, but iexpect your rail to be closer to around 34V loaded. 350VA is going to be strugglinf under fully biased V2 unless your have dual mono setup.
 
To be honest I would not use anything less that 650VA for the V2. Even better would be 2 X 500VA for a dual mono setup.

For a V3 I would definitely suggest monoblocks, with a 750VA as minimum per monoblock and 1000VA as a comfortable requirement.