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<blockquote data-quote="Nick Hickman" data-source="post: 56919" data-attributes="member: 556">Re: MythbustingRe: concerns about amplifier clipping sending high frequency energy to woofersSending HF to woofers isn&#039;t generally an issue, not least because the power content in extra HF generated by clipping is small and because the driver is inductive so its impedance rises linearly with frequency and power transferred falls linearly with frequency.Example: Apply 100W 100Hz sine wave to a hypothetical woofer.&nbsp; It sees 100W at 100Hz.&nbsp; Now apply a 100Hz square wave with the same 100W power content instead.&nbsp; If it were non-inductive, the driver would see 81W at 100Hz, 9W at 300Hz, and around 10W at 500Hz and above (falling off rapidly with frequency).&nbsp; Because of its inductance, it actually sees 81W at 100Hz, around 7W at 300Hz, and under 5W from 500Hz and up.Also, clipping a sine wave introduces energy at higher frequencies only, but clipping a signal that contains more than one frequency (like music) introduces energy at both higher and lower frequencies.&nbsp; That&#039;s one reason why, in a system with an active crossover, it&#039;s a good idea to retain a passive high-pass filter on the high frequency driver.Re: over-excursion failureThis is related to average power and frequency, not peak power.&nbsp; All else being equal, halving the frequency without changing power quadruples the excursion.Re: linked articleI haven&#039;t read it thoroughly but it seems generally on the mark.&nbsp; (There are things I&#039;d take issue with, however, like sections 5 and 10.)Nick</blockquote>

[QUOTE="Nick Hickman, post: 56919, member: 556"] Re: Mythbusting Re: concerns about amplifier clipping sending high frequency energy to woofers Sending HF to woofers isn't generally an issue, not least because the power content in extra HF generated by clipping is small and because the driver is inductive so its impedance rises linearly with frequency and power transferred falls linearly with frequency. Example: Apply 100W 100Hz sine wave to a hypothetical woofer. It sees 100W at 100Hz. Now apply a 100Hz square wave with the same 100W power content instead. If it were non-inductive, the driver would see 81W at 100Hz, 9W at 300Hz, and around 10W at 500Hz and above (falling off rapidly with frequency). Because of its inductance, it actually sees 81W at 100Hz, around 7W at 300Hz, and under 5W from 500Hz and up. Also, clipping a sine wave introduces energy at higher frequencies only, but clipping a signal that contains more than one frequency (like music) introduces energy at both higher [i]and[/i] lower frequencies. That's one reason why, in a system with an active crossover, it's a good idea to retain a passive high-pass filter on the high frequency driver. Re: over-excursion failure This is related to average power and frequency, not peak power. All else being equal, halving the frequency without changing power quadruples the excursion. Re: linked article I haven't read it thoroughly but it seems generally on the mark. (There are things I'd take issue with, however, like sections 5 and 10.) Nick [/QUOTE]

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