VAS power dissipation

Hello everyone,

I've made this design that is based on one MOSFET amplifier by Bob Cordell, but I've a question to do, the transistors Q7 and Q4, seem to have a high power dissipation, this type of package (TO92) are intended to operate with powers near 0.6 W, but the dissipation required for Q7 and Q4 is about 0.45 W which is near to 0.6 W, this could damage the transistors, I should replace those transistors or there is some measure to prevent transistor overheating?

Thank you very much for your attention,
Best regards,
Daniel Almeida


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