What you can say about lowbass and midbass perfomance for high end loudspeakers ?

@bache wrote:

"Actually more important the cone moving mass , in pro line the using
big size cone like Eminence Omega Pro 15A 15" driver with 94 gram."

The Omega Pro 15A is an excellent woofer, and as you point out its moving mass is not very high.

I’d like to use this woofer as an example to illustrate something about good prosound woofers that most audiophiles are unaware of.

Everybody knows that big cones are slow, right? Well in some cases that’s true, but not in this one. The specifics matter.

The Omega Pro 15A is arguably faster than a good 5" midwoofer, like the ScanSpeak Revelator! I’m not talking about top end extension - I’m talking about raw power-to-weight ratio ("weight" in this case being the moving mass of the cone).

We can use the formula BL^2/Re to see how much force a woofer’s motor applies to the cone for a given power input.

And we can divide that by the moving mass to get the power-to-weight ratio.

If we make this calculation, we find that the Omega Pro 15A’s power-to-weight ratio is about 30% higher than that of the 5" ScanSpeak revelator!

But that’s not the end of the story.

The Omega 15A also moves almost SEVEN TIMES as much air as the little ScanSpeak. This translates into about 16 dB more displacement-limited headroom (each doubling of displacement = +6 dB).

So the next time someone says that XYZ speaker can’t possibly be "fast" because it uses a big prosound woofer, don’t be so sure. That big prosound woofer may actually have a better power-to-weight ratio than the cute little midwoofer in your favorite mini-monitor.

Duke

prosound woofer advocate

IOW, I agree with the approach, but the explanation is an urban legend which hides a series of more complicated issues.

@bache wrote: "I agree,, except one thing, like i say before, To get low bass like 30 -40 Hz using Omega Pro 15" woofer you need box very big 5-6 Cubic Feet . You can listen nice bass with smaller enclosure , but never get really low bass."

Very true!! High efficiency + deep bass = HUGE box!

In my opinion one possible solution is to design the system with subwoofers in mind from the outset. Only about one cubic foot would be needed for the Omega 15 (and a protective high-pass filter would be optional unless you want to go north of about 118 dB). You could then tailor your subwoofer purchase to your budget and room and SPL needs.

Duke