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The QSC K12 speaker specs calls out 1,000watt power module.

Is that really 1,000 watt amplifier???

It seem most other HIGH QUALITY speakers in the $600-$800 price range are around 500 watts?

What is the gimmick here ???? 1,000 watts ?
(just for discussion)

Well it's actually a 2 channel amplifier so you have 500W to the woofer and 500W to the horn. This is very different than if you simply applied a 1000W amplifier to a passive 2-way cabinet. It's also very different from most active 2-way cabinets where usually the high frequency amplifier is less than half the power of the low frequency amp. In order for the QSC cabinet to sound right, I have to imagine there is a certain level of attenuation on the levels in the HF amplifier. Otherwise you're horn would be screaming in comparison to the low end. In other words, I doubt you'd ever see 500W going to that horn so it's almost a waste. I believe they did it this way to cut costs as it is easier to take the circuit from an existing two channel amp and plop it in the back of a speaker cabinet than to design a bi-amp circuit with different amplifiers.

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DJ Tony
Let It Rip Karaoke

Do those other speakers use a class D amplifier? The class D amplification, has eliminated the heat sinks, and the power loss has been greatly reduced, through a process very different of traditional amplifiers.

Many do (for example the latest Mackie's, latest generation JBL EON's JBL PRX series) while others do not. However, I'm struggling to see how this relates in any fashion to the discussion here. Regardless of whether it's A/B, D or another class of amplifier, the simple fact is in a 2-way powered cabinet, you wouldn't have the same power driving the horn that you'd have driving the woofer because it's a mis-match. Pretty simple speaker design concept here, it takes more power to drive a large voice coil into producing low frequencies than it does to power a titanium driver producing high frequencies of the same SPL.

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DJ Tony
Let It Rip Karaoke

Tony

Yeah I see mots 500w powered speakers usually have 400 watts to the lowend and 100w to the highs --seems to be the standard.

But why MARKET 1,000 watts if indeed it's NOT ??? - now I'm not out to bash QSC --I just want to know the TRUE output of these speakers in comparison to the comp in the same quality and price range?

Jam, simply for that reason, it's Marketing. When companies market a two channel amp they almost always market it at it's highest possible output rating. Amps capable of pushing 1800 Watts into a bridged mono load at 4ohms are marketed as an 1800 Watt amplifier, even though more realistically they might be suited to a stereo two-way system. If you look at QSC's product literature you'll notice they never actually call it a 1000W speaker system. They call it an active speaker with a 1000W power module in it. A subtle but important thing to notice. I have seen some retailers that have sloppily called it a 1000W cabinet, but that's not QSC's doing.

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DJ Tony
Let It Rip Karaoke

You don't see how this relates to his question?.... sorry, guess I'm on the wrong planet......

So JOE KJ CONSUMER is looking to buy a good 12" powered speaker - How does the QSC K12 with a 1000 watt power moduel compare to a JBL PRX512M which states 500watts total ( 400watts low - 100watts high) ???

I'm thinking that the QSC K12 should be considered closer to a 500w speaker ???

I'd agree to large extent. If you're going to compare the power of the K12 to the power specs of other active cabinets, I'd only compare the LF amplifiers in that comparison. As I mentioned before, the HF amp is going to have to be attenuated to match the output of the LF section so really from a power perspective, the LF section is your constraining factor.

So in this case, the K12 is a little ahead of a PRX512 by about 100 watts. That's the easiest way to look at it from my perspective.

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DJ Tony
Let It Rip Karaoke

Just like they market that 500 watt speaker as 500 watts when the most you'd actually hear is 400 watts.
It is the way systems are kind of rated, when someone is running a 10000 watt system in a club, it's all the amps power ratings combined. So the subs may be getting 5000 watts of that power, the mids may get 3500 of it & the highs would probably get 1500 = 10000 watts. Same applies to the smaller scale whether it be a 400 watt & 100 watt = 500 watt speaker system or 500 watt + 500 watt = 1000 watt speaker system. I have to agree that the 500 watts on the highs are probably toned down quite a bit, but like many have stated even if an amp is set at half attenuation (instead of running it wide open like one might do on an external) - it's still putting out 500 watts, as that just affects the input signal.

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