There appears to be 16 large transisitors which were mounted to the heatsink of this amplifier. It is a Planet Audio 4 channel car audio amp. From some quick Google searching, it looks like I should ...

Poised for general-purpose military and industrial applications, the CGH40090PP GaN HEMT microwave transistor boasts of superior performance over wide bandwidths when compared to GaAs MESFET or Si ...