5/5/2023 0 Comments Amp clipping detector![]() Google Patents Recovery from clipping events in a class D amplifierĭownload PDF Info Publication number US7142050B2 US7142050B2 US10/962,767 US96276704A US7142050B2 US 7142050 B2 US7142050 B2 US 7142050B2 US 96276704 A US96276704 A US 96276704A US 7142050 B2 US7142050 B2 US 7142050B2 Authority US United States Prior art keywords output integrator signal voltage clipping Prior art date Legal status (The legal status is an assumption and is not a legal conclusion. Google Patents US7142050B2 - Recovery from clipping events in a class D amplifier Which is normally there with unrestricted coil movement (well at least for bass signals).US7142050B2 - Recovery from clipping events in a class D amplifier Good power amps detect DC offsetĪlso if the coil former is held near the endstop all the time, there is much less airflow cooling around the coil (such as bursts of ultrasonic oscillation), its basically bad news all round. During a power amp clipping the feedback path is overwhelmed, often leading to other nasties Which often is more than the speaker is designed to handle continuously, so thermal failure was already When a power amp clips you are already starting at the max power anyway, With a DC offset the coil itself isn't centred in the magnet poles, so its got less cooling from the metal poles' Or rips the suspension spider/webs apart). In a clipped waveform does this - the DC holds it against the stop, the AC smashes it repeatedly against the endstop, ![]() Then you'd just pick a threshold where the estimated temperature is too hot.ĭC offsets damage speakers - both by overheating and by battering the coil former against the endstop (DC + AC as of course with lucky guessworks for those coefficients for the amount of heat and rate of self cooling. That simple linear model probably misses some minor effects, like the voice coil's copper wire resistance changing with temperature and maybe extra cooling if the woofers are physically moving air around inside a ported speaker, but it's probably good enough to get a reasonable real-time model of the approximate temperature inside the speaker. Maybe just multiply the power by some factor you believe to be the amount of heat and add it to the total temperature, and also subtract a constant for the amount of cooling over those 2.9ms. Then you'd probably try to model the speaker's temperature. You'd compute this power every 2.9ms as the library updates. Then estimate the total signal power of each filter output, probably using the RMS analysis and taking the square of the value (or if you're really crafty, maybe edit the RMS code to skip the final square root step). I would imagine using the biquad filters to emulate the behavior of the "crossover" filters feeding the midrange and tweeters within the speakers. How can one detect signals that will overload speakers (no matter how they were created)? The result was no clippping anymore but the song still sounded not well. Using Goldwave, I first applied 6dB attenuation and then applied a steep 20Hz high-pass filter. With a tool like Goldwave you can clearly see the clipping. Perhaps there are other forum members that are more knowledgeable on this topic.Īs a side note: I once tried to cleanup the Madonna song "Ray of Light" which clips on every CD version I found (so much for the Sony recording/mastering engineer ahum.). 20Hz to filter out DC components but I'm not sure that will work satisfactorily. Theoretically you could apply a steep high-pass filter set to e.g. It may cause damage to the amplifier's power supply or simply blow a fuse." This extra power can damage the loudspeaker. "Because the clipped waveform has more area underneath it than the smaller unclipped waveform, the amplifier produces more power than its rated (sine wave) output when it is clipping. I dont understand why a "clipped" Signal should damage speakers just by being "clipped", whatever clipped means.
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