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The graph referred to in post #60 was to the winisd modeling which shows the driver can reach 110db with just 50w input power. So I am assuming based on that that as long as I keep under that the cone excursion is not exceeded.

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I am referencing post #60, on page 3 of this thread. Right, the driver reached 110db with 50v input power, but only at 60hz. Reference level is for all frequencies, not just 60hz.

You're right, your posted measurments show flat to 10hz, but that is at a fairly low SPL level of only 80db. If that's as loud as you ever listen to movies, then I agree you're fine. But you were originally talking about reference level, 115db. If you were to watch a movie at reference, and that movie had content in the 10-20hz range, as many action movies do, then I'm guessing one of two things will happen:

1) If you're limiting your power to the subs at 50V, then they will not reach reference level below 60hz, at least not unless you've got a bunch of room gain to help. A compression test up to 115db in your room could show this.
2) If you don't have a limiter, then the drivers will pull more than 50v to reach reference level below 60hz, which will increase excursion and could cause bottoming/sub damage at low frequencies.

All depends on what content you're watching and at what levels. If you're listening at closer to 80db than 115db and thus keeping your subs to 50v or less, then I'd agree you'll never have any issues without a HPF. The issue would be running a bass heavy scene like Edge of Tomorrow or War of the Worlds at reference, which for all I know you have no interest in ever doing.[/QUOTE]

I think we are saying same thing and your message has a typo 50w not 50v.

If I say that the power requirement of 50w produces peak output of 110dB at 60hz (plus 6dB room gain will result in hitting reference) and as long as I keep it under that I am safe, the same applies to the 10hz as well. Of course the requirement for power could be a bit higher but as I showed in REW my graph is relatively flat as in I am getting tons of room gain. So As long as I am not playing at reference level and below that at say 80 or 90db, my input power requirement is not going to exceed 50w and hence I will be under cone excursion at 10hz too.

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These ain't casual listeners though, you're in the land of excess, bent cones and melted voice coils. Need a high pass filter and some holy water to keep these suckers from catching on fire.
I laughed out loud at that one. I had a mental picture like a scene from "The Exorcist" of someone trying to coax more low end output out of their subs. :LOL:
 

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My early post was directed to the thread starter who said:
"Do these subs require high-pass filters or some sort of digital control? I don't want to blow them up by sending 15hz signals to them or something."
My post was germane to that thread starter. Then it appears some folks began talking about high pass filters, no matter what subset, confusing them with low pass filter function and control.
I think you've misunderstood what Snoochers was asking. The OP isn't using his sub as a "passive subwoofer" as you are thinking. He mentioned getting an iNuke so he will be powering his sub using a dedicated subwoofer amplifier rather than powering his mains and sub off of his L & R speaker outputs from his AVR. He was asking if a high pass filter was necessary to roll off low frequencies below tuning to protect his driver from damage. I've posted a pic below of how a high pass filter is applied using MiniDSP which is what the original poster is asking about.

3096125
 

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I think you've misunderstood what Snoochers was asking. The OP isn't using his sub as a "passive subwoofer" as you are thinking. He mentioned getting an iNuke so he will be powering his sub using a dedicated subwoofer amplifier rather than powering his mains and sub off of his L & R speaker outputs from his AVR. He was asking if a high pass filter was necessary to roll off low frequencies below tuning to protect his driver from damage. I've posted a pic below of how a high pass filter is applied using MiniDSP which is what the original poster is asking about.

View attachment 3096125
Thank you for your cordial comment. I get the gist of the thread now.
 
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