Frosty_47
New Member
Thank you for your feedback
At +/- 30V the current idles at 1.0Amp. Even when I blast the speaker, the current from the power supply does not exceed 1.3Amperes. The Mosfets produce a lot of heat. I attached them to separate P3 CPU heat sinks with fan so that keeps them at ambient temperature level.
I will try the negative feedback with C1 removed as you have suggested.
Mosfets have a very wide range of drain to source resistances. Unless you measure yours they might be well-matched or be either way mis-matched. The negative feedback should take care of the difference.
You will not be able to buy a "matched pair' of complementary Mosfets. Amplifier manufacturers buy thousands and match them themselves.
Usually the circuit adjusts the bias and feedback on the Mosfets to match them.
Your second circuit with the feedback connected properly to the Mosfets has the Mosfets idling at a very high current that might overheat them.
At +/- 30V the current idles at 1.0Amp. Even when I blast the speaker, the current from the power supply does not exceed 1.3Amperes. The Mosfets produce a lot of heat. I attached them to separate P3 CPU heat sinks with fan so that keeps them at ambient temperature level.
I will try the negative feedback with C1 removed as you have suggested.
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