Pair Hitachi MOSFET's, 2SJ50 + 2SK135, Likely manufactured late 80s / early 90s

Pair Hitachi MOSFET's 2SJ50 + 2SK135. These Lateral MOSFET's were produced by Hitachi starting in the 1970s and were developed specifically for linear audio amplification. They quickly earned legendary status in the audio industry but sadly Hitachi ceased their production in 1993.

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