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<blockquote data-quote="John Roberts" data-source="post: 114093" data-attributes="member: 126">Re: NAMM 2014 reportNot to put too fine a point on this. I actually wrote about this in my old &quot;Audio Mythology&quot; column back in the &#039;80s. The primary difference and source of problems with caps used in passive vs active crossovers is the current. A passive crossover cap is passing the full current coming from the amp and going to the loudspeaker driver. In an active filter, the current is rarely even mA level (thousandths of an amp). All the subtle non-linear impedance aspects of real world caps become amplified by the high current and audibly significant. DSP that doesn&#039;t even use capacitors to make filters can be arbitrarily linear and accurate.&nbsp; If they both offer the same performance the simpler the implementation the more reliable, while I wouldn&#039;t expect performance to really be the same. Yes, the customer is entitled to know, and marketers bend over backwards to give them any information they think will be perceived positively and influence their purchase decision. It is cranky old design engineers like me that don&#039;t appreciate the second guessing by customers who mainly don&#039;t know what they don&#039;t know. For every Douglas Allen there are several thousand with opinions but no clue.YMMVJR</blockquote>

[QUOTE="John Roberts, post: 114093, member: 126"] Re: NAMM 2014 report Not to put too fine a point on this. I actually wrote about this in my old "Audio Mythology" column back in the '80s. The primary difference and source of problems with caps used in passive vs active crossovers is the current. A passive crossover cap is passing the full current coming from the amp and going to the loudspeaker driver. In an active filter, the current is rarely even mA level (thousandths of an amp). All the subtle non-linear impedance aspects of real world caps become amplified by the high current and audibly significant. DSP that doesn't even use capacitors to make filters can be arbitrarily linear and accurate. If they both offer the same performance the simpler the implementation the more reliable, while I wouldn't expect performance to really be the same. Yes, the customer is entitled to know, and marketers bend over backwards to give them any information they think will be perceived positively and influence their purchase decision. It is cranky old design engineers like me that don't appreciate the second guessing by customers who mainly don't know what they don't know. For every Douglas Allen there are several thousand with opinions but no clue. YMMV JR [/QUOTE]

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