Paul Walters wrote on Sun, 01 August 2010 13:37 |
Is it then your opinion that the maximum power that should be delivered to this driver is 1250 watts? (Ignoring the box, if that's possible for a theoretical situation.)
Why did I see posts about this driver needing 2000 watts? Is the practice of doubling RMS power not applicable to this particular driver?
Also, I would love to toss these enclosures and build a new one, but it might be more economical to simply buy something like a Peavey SP218 used and sell what I have.
Alternately, would it be possible to buy a dual 18 enclosure with blown subs and install these drivers?
If I do have to run these subs for a while, would it be safe to run each at 500 watts and a 40Hz hi pass filter and crossover at 100Hz?
Thanks for your help thus far! Sorry that I'm so new to subs, but I'm here to learn!
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Drivers don’t “need” power, they require power to deliver sound output.
You can’t ignore the box, the driver’s excursion is controlled by the box.
If you study the various boxes, you will see the relationship between excursion and frequency.
You will see excursion is at minimum at Fb, rapidly increases below Fb, and has an increase above Fb that reduces again at higher frequencies. Smaller boxes limit the excursion above Fb.
The Kilomax voice coil can handle 1250 watts. Like any other decent LF driver, it can easily handle musical peaks of two or more times that.
If you were to run a sine wave, or severly compressed music, 1250 watts would be all the voice coil is rated for.
But most music has less than 1/3 the average power as peak, so the speaker seeing 1250 watt peaks is probably getting less than 400 watts average.
The Kilomax Xlim, the maximum mechanical limit, is 19.2 mm.
If the power is sufficient to reach Xlim, the speaker may be torn up instantly, hence the need for a proper HP filter.
If you look at the excursion vs. power, you see that very little power is needed to reach Xlim below the box tuning, Fb.
Power between Xmax and Xlim will not tear up the speaker instantly, but will make distortion rise rapidly.
As far as safety at 500 watts and a 40Hz hi pass filter and crossover at 100Hz, power up the cabinet and measure the peak to peak cone motion and divide by 2. A dot of white paint can make the cone excursion easier to read.
If it is less than Xmax (10mm) 3/4” peak to peak, the cone is safe from excursion damage.