Re: New Lightweight Power Amp Ratings
I wrote about this at length back when Bink did his big power amp shoot out years ago. Measuring amp duty cycle is not the hard part. The hard part is coming up with meaningful less than 100% duty cycle targets that customers can look at and determine if it is more or less than they need. The marketplace has spoken very loudly that they will not pay for 100% duty cycle amps, and will reward amps that cost effectively give them just enough without making them pay for excess capability that they don't need. Putting a number to this opens up an arms race between the amp makers to deliver, just a little more than the next guy, while not so much it hurts pricing/profit.
Ironically perhaps the higher the power point, like with modern big dog amps, the less likely you could ever use 100% duty cycle (even you Tim).
It might be of academic interest for some to know which amp puts out more duty cycle than others in a "my thing is longer than your thing" way, but as long as it puts out enough that is all that is needed for cost effective performance (at least that's what she said.)
The difficult thing about trying to define a X% (less than 100%) duty cycle test stimulus waveform, is what test waveform could possibly represent all customer's typical needs. As I have posted already a mirror image variant of something like loudspeaker power handling tests (band passed noise) could come up with "a" number but not "the" number.
i see no incentive for manufacturers to come up with a new specification, that they would all just try to game for marketing advantage. From my past experience with consumers misunderstanding even simple amp specs, something this complex would probably cause more bad decision making than good with power amp purchases.
The best gauge IMO for new power amps is to listen to early user reports. They will quickly determine if they hang or not. If weak, the new amp will sink to some appropriate user level, or go away if not a true value. If strong they will win increasing market share as the word gets out and they up the cost/benefit calculus.
A appreciate this is rather unscientific, but i do not believe more science would actually help consumers. Amps have been in this "less than 100% duty cycle" gray area for decades and managed so far. Modern technology is making it easier/cheaper to deliver more duty cycle (using saturated switch outputs) so this should become less of an issue not more. While value amp makers are always rewarded for working the margins and pushing the envelope.
Trust (no one) but verify....
JR
PS: As I have also mentioned amp designers routinely use some favorite pre-recorded tracks or maybe a board tape that works for them to represent their customer's expectations. It would be pretty easy to come up some standard sound files, but less easy to make them universally meaningful, for all customers and all applications.
