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<blockquote data-quote="Art Welter" data-source="post: 148418" data-attributes="member: 52">Re: 60 Degree&nbsp; DIY Mid HiCrest factor is the peak amplitude of the waveform divided by the RMS value of the waveform.When expressed in decibels, crest factor and PAPR (peak-to-average power ratio) are equivalent.The PAPR is most used in signal processing applications. As it is a power ratio, it is normally expressed in decibels (dB). The crest factor of the test signal is an important issue in loudspeaker testing standards, it is usually expressed in dB.The minimum possible crest factor is 1, 1:1 or 0 dB for a DC or square wave signal,&nbsp; they have double the average peak-to-average power ratio of a sine wave (3.01 dB PAPR) and therefore will heat the voice coil (or resistor) twice as much.This is the reason why clipping an amp will burn up drivers more than an unclipped amp. The voltage is no greater when clipped, there is just more average power delivered, and the harder the amp is clipped the closer it comes to delivering twice as much (+3dB) more average power than it&#039;s sine wave rating would indicate.The AES compressed pink noise signal PAPR is 6 dB, half the PAPR&nbsp; of a sine wave, and about twice PAPR of (compressed) music.Run a 700 Hz square wave through your Lake RMS detection and your driver will dissipate about 12 times more power (heat) than with music.Don&#039;t believe it? Put your finger on an 8 ohm load resistor and try some acoustic music through it at limiter threshold, then repeat with a square wave and you will feel the difference a lot faster than it has taken to read about it.Art</blockquote>

[QUOTE="Art Welter, post: 148418, member: 52"] Re: 60 Degree DIY Mid Hi Crest factor is the peak amplitude of the waveform divided by the RMS value of the waveform. When expressed in decibels, crest factor and PAPR (peak-to-average power ratio) are equivalent. The PAPR is most used in signal processing applications. As it is a power ratio, it is normally expressed in decibels (dB). The crest factor of the test signal is an important issue in loudspeaker testing standards, it is usually expressed in dB. The minimum possible crest factor is 1, 1:1 or 0 dB for a DC or square wave signal, they have double the average peak-to-average power ratio of a sine wave (3.01 dB PAPR) and therefore will heat the voice coil (or resistor) twice as much. This is the reason why clipping an amp will burn up drivers more than an unclipped amp. The voltage is no greater when clipped, there is just more average power delivered, and the harder the amp is clipped the closer it comes to delivering twice as much (+3dB) more average power than it's sine wave rating would indicate. The AES compressed pink noise signal PAPR is 6 dB, half the PAPR of a sine wave, and about twice PAPR of (compressed) music. Run a 700 Hz square wave through your Lake RMS detection and your driver will dissipate about 12 times more power (heat) than with music. Don't believe it? Put your finger on an 8 ohm load resistor and try some acoustic music through it at limiter threshold, then repeat with a square wave and you will feel the difference a lot faster than it has taken to read about it. Art [/QUOTE]

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