This listing includes four pieces of IRFP240 power MOSFET for audio amplifier output stage application.
The four parts are tightly matched for diy audiophile projects.
For tightly matched we are referring to the below criterion :
1. The four pieces have to be from the same batch ;
2. The four pieces have Vgs matched to 50mV variation with the same drain current of 1A or over to suit class A amplifier operating condition.
We use our in-house designed fixture for the matching. The circuit is as the picture below with drain current running at 1A or higher and use Agilent( now Keysight) 34401A six and a half digit multimeter to do accurate and fast response measurement.
This is our always method for matching of power mosfets.
Those using simplistic transistor tester ( such as MK-328 transistor tester) cannot give the right results. The 006P 9V battery in the transistor tester is unable to give enough current even to turn on the MOSFETs !
