A warning to all about HUGE Subwoofers

So I just bought a Velodyne HGS18 yesterday and its amazingly awesome. Enough so that I know that it can crack concrete and after playing with it a while i genuinely have realized this has the potential if unleashed to destroy a house.

I decided to do a test tone to see how it did and at 10HZ this thing will rattle your whole house (I listen to rap amongst other things, I'm no stranger to playing loud bass)and that is with very little volume. Be careful when you look at subs in accordance to your building.

I always thought the subs that had that potential were awesome and amazing which they are (at least this one) However it isnt fun be afraid to turn up your sub for fear of tearing down your walls. It wasnt that bad but it seems that in 2 seconds or less if its going to loud and low it could do some damage. I can only imagine what it would have done my volume was any higher or if i let it go without being next to the volume switch.

On a side note hearing frequencies that low is an amazing improvement and far better than I had anticipated
I'm going to contact my insurance agent and see if subwoofer damage is covered by my policy. Thanks for the warning.
I remember when the Outlaws cracked the foundation at the Syria Mosque in Pittsburgh. Amazing venue until they tore it down.
I would suspect that it would only be a significant structural issue if your house has a resonant frequency that the subwoofer if matching. Sounds like you might be experiencing this situation.

I heard a subwoofer demo at my local dealer that was done with a JL Audio subwoofer and it was really impressive. The only thing that rattled in that room was a single light fixture that need to be fixed. They said that they had do some maintenance on the light fixtures from time to time to minimize the rattling.

My little Martin Logan Dynamo 700 subwoofer was rattling my laminate floor over the subfloor. I put the spikes on and it got worse so now it's converted to forward firing and is working perfectly. Similar issue on a smaller scale.
Interesting post. FWIW, take a look at some of my recent posts relating to my new impedance buffer and also on potential hearing loss. As regards the impedance buffer, I mentioned in part that my sub woofer crosses over to my main speakers at 45-50 Hz. Yet there "seemed" to be very little SPL generated out of the sub, presumably (??)because there's not a lot of input source in the lowest registers. My point here is that if my surmise is correct, then I'm curious about your your source material. Could it be low frequency noise??

As regards, hearing loss, I think the thread is self explanatory. Watch out for excessive SPL for extended periods of time. As I recall, SPL of 115db can cause permanent hearing loss after just 30 seconds!! ETM!
My dog fears my JL subs. She gets up and runs down the hall to mommy and hides under the comforter when I play it loud.

A question for you though:

Precisely what instrument are they playing, (especially in rap music), that goes that low in the frequency response?

(Just curious is all.)
Kurt tank,
I believe that the lowest frequencies you can get from upright double-bass and tum-tum if recorded with no overdubbing and filtering.
I ask, because when I looked at this website - see below, (and this is pretty much in accordance with my understanding), that the frequency response of all acoustic instruments is much higher than the 10 Hz frequency response mentioned in the original post.
(Barring organs of course, which is not used too often in rap music, at least not the last time I heard it.) Even an electric bass guitar does not go much lower than 40 Hz.
And only the really big bass drums only go down to about 20 Hz, (and those are typically only used in large symphonies, not rap bands).

Musical Instruments Frequency Response

Again, I was just curious. The only thing I can figure out is that they are using synthesizers to produce the artificial drum sounds that reach as low as 10 Hz. In which case, what do they do in concert? (Not that I would ever go to a rap concert, but again, just curious.)

(FYI, I can see why one needs a subwoofer for Home Theater, as there are explosions and such which can be below 10 Hz, (and of course the thrill of being hit in the chest with a big bass wave is cool). And yes, I have one for my HT too.
But for most music, it seems going down below 20 Hz is overkill. (Heck, maybe anything below 30 Hz is overkill for most music.) And yes, I have speakers that are probably somewhat overkill in the bass range myself, (EgglestonWorks Andra II speakers), but they are not designed to go down to 10 Hz.)

Just thinking out loud.
The larger the subwoofer or bass system the less it will cause issues with peaks and nulls or as you would say vibration in room walls furnishings.
Great post Kurt. Your post and the attached chart corroborate my empirical findings when I hooked up my impedance buffer. I also agree that it is curious what is causing the low frequency SPL in Systembuilder's woofer. As you speculate, maybe its synthesizers???
The old "acoustic instruments only go down to" statements always show listeners' musical tastes and biases. Am I the only one who likes Aphex Twin, William Orbit, and other electronica artists? They are lucky to not be hindered by the limitations of acoustic instruments in their artistic endeavors. Anybody wanna challenge the artistry of electronica? I am listening to Rachel Podger playing Bach Violin Concertos and my subs aren't hurting a thing. I may switch to Four Tet in a little while and I'll be glad I have the subs so I can hear all they intended me to hear.
The military might be interested in your subwoofer.
They could use it as an Acoustic Weapon.

Frequency & effects:
7 Hz: Supposedly the most dangerous frequency corresponding with the median alpha-rhythm frequencies of the brain. It has also been alleged that this is the resonant frequency of the body’s organs therefore organ rupture and even death can occur at prolonged exposure.

Just some interesting information I found out there.
Careful in that listening room.
Guys all he did was play a test tone. Yes, synths will get you to 10hz or lower i guess. BTW, I doubt even in rap and electronica/synth has that much info at 10hz.
You guys are awesome, till now I was looking to satisfy my >20KHz fantasy, now I have more the 20 below
10 Hz almost has to be a test tone. Even large pipe organs don't go much, if any, below 16 Hz. What would be the point of recording sounds that low anyways? The percentage of people that actually have equipment to reproduce it is a small subset of the already small subset of audiophiles.
Just don't move to my neighborhood. WE have big guns, and know how to use them.
Enough so that I know that it can crack concrete and after playing with it a while i genuinely have realized this has the potential if unleashed to destroy a house.
And another unsubstantiated 'urban myth' gets disseminated on the Internet.
Hi I did the first post, I realized after I posted that while the test tone was the first Eye-catcher er Ear-catcher was the test tone.

I then threw on E-40 (Local Bay Area Rapper) and turned the amp to my speakers off to see what it could do, go figure it wasnt coming in loud at the beginning so all of a sudden its truned up higher and a peak hits and it scared the hell out of me. I know what I heard (The sub can go a lot louder! it was at 30% internal volume and my preamp was at 9 or 10 oclock ). I just figured I can control myself but a friend with a few drinks in him who doesnt know whats what and all of a sudden your walls dont fall down but little cracks open up allowing drafts in the house maybe who knows. I just didnt realize

In response to kurt
I have noticed a large upgrade (Velodyne HGS-12 to HGS-18) In all types of music I listen to so far both electric and acoustic. Far more than I could have anticipated. I am actually on a side note for the first time ever listening to my electronica CD's I had lying around and you need a HUGE Sub to appreciate it.

As far as rap shows go, The ones I have been to have been about as Black and white as it gets. Some have good setups and actually are setup pretty decent for what it is. Others just dont care when the woofer start what I would call farting. But I would believe that running that high of power and having that large an area to fill you would have to be going sub 20HZ, at all the good shows its good and deep. At the bad ones just dont go grab a girl in the parking lot walking out whos already tipsy and save your ears literally. KRS-ONE Is the only consistent rapper worth seeing and he actually does a good number of free shows for charity each year

Your my kinda people, I like space between me and my neighbors anyway

It really is amazing what it does for everything there is a form of connectedness I have not felt in my system before and my HGS-12 is no slouch. To all the non believers and just thinking its louder, I wasnt expecting it be any louder buying it (Ok I did but thats not why I got it) I bought it because that low deep bass is such an amazing luxury to get to experience and it connects you so well to the music. It is a whole different and far better experience and I say this owning a pair of Focal Utopia 11" Subwoofers (In 2002 were the fastest subs ever made to the best of my knowledge and might still be) which offer so much more speed and I dont care, The depth is just awesome!
"And The Walls Came Tumbling Down"
They had acoustic weapons thousand of years ago.
Heck I can kill termites with a dd10. I only need to find their resonant frequency.
I used 2 HGS 18 subs with a rear ML descent sub. I used to play all 3 as loud as they could go. This was all the time for 2-3 years.NEVER had one issue. Not even a picture off the wall from other nearby rooms.

I can tell you a HGS 18 isnt strong enough to do damage. I run much better subs these days and still no issues.
The only damage my subwoofers caused was the drywall screws backing out , you could see rows of screws where the studs were . they got so bad that I had to rescrew the walls then laminate a second layer of drywall to the first layer using no screws or nails , problem solved .
I had great seats for a few of the Pink Floyd Division Bell shows and "Sorrow" taught me that bass can rattle all the little bones in your ears. Not very comfortable.
If your dog was stuck under the house and kept barking would that be considered a "sub woofer"...? Just thought I'd ask...
05-01-11: Sounds_real_audio
So how does the sub integrate into your system. Is it seamless?

My room is an L Shape about 12' Wide by 20' deep turning into an L about 10' in so i have HUGE suckout and there is no door just a 5x6 doorway so I dont have an Ideal or even all that great room but it works for now until I save enough to Remodel (Really Rebuild) a garage/storage unit on my property maybe 30 feet from the pole (maybe 70 feet from the transformer) and make that my listening room 15 feet wide by 20 or so deep would work just fine.

Back to the question, not entirely shockingly and I do meant shockingly better than the HGS-12 which I thought would have quicker speed but no, it keeps up, I even tried it at 80HZ and its no slouch, and I cant recommend anything I have heard better for acoustic music, Im not getting the output I dreamed of but my room sucks
The only damage my subwoofers caused was the drywall screws backing out , you could see rows of screws where the studs were . they got so bad that I had to rescrew the walls then laminate a second layer of drywall to the first layer using no screws or nails , problem solved .

Thats actually very impressive. What subs you use?
I have 2 ads m4's and 2 ads m3's in my system.
The 4's are on the fronts, the 3's are on the sides.
My system in a finished basement and I can shake
the cement floor.
It's taken me months to stop all the rattles, but
it is worth it.
I tuned everything to be flat and smooth on the low
It sounds great, but on some recordings I hear tapping
on the floor or mike boom vibrations that can make
you nauseous.
Years ago I heard a parrasound 18 inch sub and it knocked
me out of my chair, but was clean and fast.
Would love to hear it again,
Of course no system is really high end and all that unless it's got the balls needed to destroy the house, right?
The true test of an audiophile system...." does it make the wax fall out of your ears?"
If your system can not pressurize your listening space you are for sure missing something wonderful. If this doesn't mater to you nothing wrong with that. But without the pressure detail across the range is missing. And the excitement and suspension of disbelief is greatly diminished.
If your system can not pressurize your listening space you are for sure missing something wonderful.
But no buildings were harmed in the pressurising of this space :^)
I run and offer some of the largest and most powerful bass systems on the planet. I do not damage my home. I use a bass horn equal to 6-8 18in woofers in ported cabinets I use this as part of my office system. While I can pressurize a large hall with it also works well for Movies gaming as well as music in smaller space. We also offer the Fostex 31.5 in super woofer as well as other bass horns inc the 4-18 with 4 18in drivers. No customers have damaged there homes though one did have bird fly into his bass horn he turned it up a wee bit to chase out bird the pressure in horn killed it.