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Old 27th August 2006, 04:12 AM   #21
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Thats kind of moronic, because the frequency response of the amp on the low end is 20 hz...what is the point in having a 15 hz ssf then...

lol
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Old 27th August 2006, 04:14 AM   #22
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Now when you were saying "unload", were you referring to driver over-excursion?
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Old 27th August 2006, 04:40 AM   #23
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I was referring to the phenomenon that occurs when you play a ported speaker more than ~1/2 octave below tuning, in which the port no longer acts like a port and instead acts like a giant hole in the box, drastically increasing driver excursion for a given amount of power. So you're playing your music, everything's fine and the sub is happy, then along comes a low note or a frequency sweep that goes below the box's tuning frequency and *pop*, there goes the sub.


Unloading itself doesn't mean overexcursion, after all when the sub is unloading it's simply behaving as if it wasn't in a box at all, which obviously doesn't destroy it in and of itself. The problem is that the mechanical power handling of the sub is very high between ~1/2 octave below tuning and ~1 octave above tuning, so you can push it very hard in that range (which for a sub, is basically its entire usable range), but once you get below ~1/2 octave below tuning, the mechanical power handling of the sub goes out the window, and if you still happen to be feeding it the gross amount of power you were feeding it above tuning, it will over excurt and rip itself apart.
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Old 27th August 2006, 04:46 AM   #24
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Quote:
Originally posted by sr20dem0n
I was referring to the phenomenon that occurs when you play a ported speaker more than ~1/2 octave below tuning, in which the port no longer acts like a port and instead acts like a giant hole in the box, drastically increasing driver excursion for a given amount of power. So you're playing your music, everything's fine and the sub is happy, then along comes a low note or a frequency sweep that goes below the box's tuning frequency and *pop*, there goes the sub.


Unloading itself doesn't mean overexcursion, after all when the sub is unloading it's simply behaving as if it wasn't in a box at all, which obviously doesn't destroy it in and of itself. The problem is that the mechanical power handling of the sub is very high between ~1/2 octave below tuning and ~1 octave above tuning, so you can push it very hard in that range (which for a sub, is basically its entire usable range), but once you get below ~1/2 octave below tuning, the mechanical power handling of the sub goes out the window, and if you still happen to be feeding it the gross amount of power you were feeding it above tuning, it will over excurt and rip itself apart.
Ok so you can use the SSF to prevent (or eliminate the possibilty of) both cone over-excursion and unloading of the driver?
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Old 27th August 2006, 06:19 AM   #25
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You could still overexcurt the driver at other frequencies, the SSF just prevents it from being overpowered while unloading

But that's only if it's set near the tuning frequency, a 15Hz SSF wouldn't do much of anything unless you tried feeding your sub a 10Hz tone.
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Old 27th August 2006, 06:53 AM   #26
soho54 is offline soho54  United States
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Thats kind of moronic, because the frequency response of the amp on the low end is 20 hz...what is the point in having a 15 hz ssf then...
That is just the rated freq. responce. It will still provide output under 20hz. Most amps are good to 5-8hz.
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Old 27th August 2006, 06:36 PM   #27
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Originally posted by soho54
That is just the rated freq. responce. It will still provide output under 20hz. Most amps are good to 5-8hz.
Alright, if my fsc is 32.83 hz and the driver overexcurts at 29.26 hz, is it necessary to use an SSF to prevent unloading and overexursion of the driver?
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Old 27th August 2006, 06:46 PM   #28
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And if so, what should I set the SSF at?
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Old 27th August 2006, 07:09 PM   #29
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Quote:
Originally posted by rocko1290
Alright, if my fsc is 32.83 hz and the driver overexcurts at 29.26 hz, is it necessary to use an SSF to prevent unloading and overexursion of the driver?

It would be a good idea, but it's never "necessary". If you were to feed your sub 1 watt, it would never overexcurt, regardless of tuning or what it's playing. It's all about what you like to listen to, how loud, etc.

Other brands that can do 600@2ohm? That's what you said last page, but then you started another thread asking for 600@4ohm. Those are 2 completely different amps that you would be looking for. The 2ohm amp would most likely be a relatively mid priced mono amp. The 4ohm amp would most likely be a strong 2ch amp that's been bridged.

Or the JL 500/1 could do both
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Old 27th August 2006, 07:13 PM   #30
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Quote:
Originally posted by sr20dem0n



It would be a good idea, but it's never "necessary". If you were to feed your sub 1 watt, it would never overexcurt, regardless of tuning or what it's playing. It's all about what you like to listen to, how loud, etc.

Other brands that can do 600@2ohm? That's what you said last page, but then you started another thread asking for 600@4ohm. Those are 2 completely different amps that you would be looking for. The 2ohm amp would most likely be a relatively mid priced mono amp. The 4ohm amp would most likely be a strong 2ch amp that's been bridged.

Or the JL 500/1 could do both
The reason is because I decided to switch drivers and the new driver is 4 ohms. I do not know how to bridge amp channels....

What should I set the SSF at in the above-mentioned case?
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