🔍 Key Concepts

• How feedback and regeneration work in audio circuits (positive feedback causing oscillation/howl) • How component failures (like tubes and resistors) can create instability or oscillation in audio equipment • The meaning of answer choice "All of the above" in multiple-choice technical questions

💭 Think About

• Which of these conditions could introduce unwanted feedback or instability in an audio circuit that might be heard as a howl? • Could more than one of these faults reasonably cause oscillation or feedback in a sensitive audio system? • When you see an "All of the above" option, what should be true about each individual choice for that to be correct?

✅ Before You Answer

• For each choice (A, B, C), ask: Can this fault or setting reasonably lead to feedback/oscillation? • Confirm whether regeneration/feedback controls, tubes, and grid resistors are all involved in controlling signal stability and noise. • Before picking "All of the above", make sure none of the individual options is clearly unrelated to causing audio howl.