Why do subwoofers need to be so big and heavy?

[kystorm]

Not sure how the thing sounds, but I see something like this as a step in the right direction if you're not into space hog subwoofers.
sub linky

 

[lovinthehd]

Not sure how the thing sounds, but I see something like this as a step in the right direction if you're not into space hog subwoofers.
sub linky

You just give up performance for the small form factor....Hoffman's Iron Law and all that The unspecified lower frequency response of 32hz isn't encouraging, probably limited in output as well. This might be fine for some uses but with its limited extension not really going to substitute for a proper sub for home theater in any case. Similarly you could use tactile transducers mounted to furniture, risers, flooring, etc.

 

[Steve81]

so could you possibly humor us with a design that is light and small and amazing? Just curious to see how you’d do that.

Infinite baffle

Of course, depending on one's definitions of small, light, and amazing, a 15" driver capping each end of a sonotube in a sealed, dual opposed arrangement could be done in a reasonable volume (say 4 to 5 cubic feet), weigh under 100 pounds, and be capable of respectable output. It wouldn't walk either given the force cancellation inherent with DO.

 

[shadyJ]

It wouldn't walk either given the force cancellation inherent with DO.

I wouldn't be so sure of that. Dual opposed only cancels out rocking motion in one direction of travel. The cabinet itself will still resonate. You still don't have even force on the sub if you stand it up right, thanks to gravity.

 

[Steve81]

Dual opposed only cancels out rocking motion in one direction of travel.

Not sure why that would be the case. The forces applied to the two drivers will always be opposing one another after all.

In any event, the dual opposed cylinder configuration has been around for quite a while, i.e. bossobass' subwoofers. AFAIK, he's got a video showcasing the relative inertness of the design w/ a wine glass out there somewhere. There's this one of the SubM as well.

 

[lovinthehd]

Not sure why that would be the case. The forces applied to the two drivers will always be opposing one another after all.

In any event, the dual opposed cylinder configuration has been around for quite a while, i.e. bossobass' subwoofers. AFAIK, he's got a video showcasing the relative inertness of the design w/ a wine glass out there somewhere. There's this one of the SubM as well.

LOL was just looking to see if Dave had any info on the weights of his Raptor or Raven subs....couldn't find any. Have wondered if occasionally you need to invert one of his to ward off the effects of gravity for the drivers, tho. My Empire (another DO 15" but normal orientation) is very inert, one of those coin on edge demos was one of the factors that led me to buying it.

 

[Steve81]

LOL was just looking to see if Dave had any info on the weights of his Raptor or Raven subs....couldn't find any.

You can find a few more details about the Raptor, including weight, here.

 

[lovinthehd]

You can find a few more details about the Raptor, including weight, here.

Thanks, a bit heavier than I expected....

 

[Steve81]

Thanks, a bit heavier than I expected....

To be fair, the drivers he uses probably account for ~90lbs of that.

 

[lovinthehd]

To be fair, the drivers he uses probably account for ~90lbs of that.

I wasn't thinking they were quite that much....would love to see the breakdown, tho and just what the sonotube is alone....

 

[Verdinut]

Not sure why that would be the case. The forces applied to the two drivers will always be opposing one another after all.

In any event, the dual opposed cylinder configuration has been around for quite a while, i.e. bossobass' subwoofers. AFAIK, he's got a video showcasing the relative inertness of the design w/ a wine glass out there somewhere. There's this one of the SubM as well.

IMO, that video looks weird. I don't believe what was advanced, because there's no bass in the audio track . If the top of the enclosure is level, with that kind of crappy music played with no bass, there is no reason for the cabinet to vibrate and the pennies won't move or fall.

 

[Steve81]

IMO, that video looks weird. I don't believe what was advanced, because there's no bass in the audio track

You might consider the comment accompanying the video:

At a recent home theater meet I was listening to a Seaton speaker demo and we stood a nickel and dime up on the subwoofer to show how the cabinet doesn't vibrate. We were listening at Reference at the time. This vid was taken with my phone camera so the quality stinks, but you should get the idea. This is a fantastic sounding sub and obviously very well built. Remember, this was taken with my phone and I can assure you the sound was not distorted in any way!! And if I can go on a tangent, I hate my phone. It's a Verizon Voyager and the only thing I like about it at all is the keyboard. Crap camera, poor build quality (on my fourth),and the speakers aren't all that good. However, never had a prob making a call so I guess that's a plus since it is afterall a phone first. I'll be upgrading to the new Tour very soon.

Of course there are others who will vouch for the deadness of the SubM's enclosure, and obviously lovinthehd mentioned seeing another such demonstration (in person?) with the Epik Empire.

 

[Verdinut]

You might consider the comment accompanying the video:


Of course there are others who will vouch for the deadness of the SubM's enclosure, and obviously lovinthehd mentioned seeing another such demonstration (in person?) with the Epik Empire.

Now I understand and I don't doubt the quality of the subwoofer. When are you getting a hi-fi phone with a condenser mike having a flat response from 16-20K ?

 

[Steve81]

I wasn't thinking they were quite that much....would love to see the breakdown, tho and just what the sonotube is alone....

You could always shoot Dave an email WRT the driver, all I can say is this:

Now I understand and I don't doubt the quality of the subwoofer. When are you getting a hi-fi phone with a condenser mike having a flat response from 16-20K ?

Thankfully, it's not my cell phone

 

[lovinthehd]

I wouldn't be so sure of that. Dual opposed only cancels out rocking motion in one direction of travel. The cabinet itself will still resonate. You still don't have even force on the sub if you stand it up right, thanks to gravity.

If in phase wouldn't that be two directions of travel?

 

[shadyJ]

If in phase wouldn't that be two directions of travel?

What I meant is one plane of motion.

 

[lovinthehd]

What I meant is one plane of motion.

LOL I know....

 

[kystorm]

You just give up performance for the small form factor....Hoffman's Iron Law and all that The unspecified lower frequency response of 32hz isn't encouraging, probably limited in output as well. This might be fine for some uses but with its limited extension not really going to substitute for a proper sub for home theater in any case. Similarly you could use tactile transducers mounted to furniture, risers, flooring, etc.

Yeah prolly wouldn't meet most peoples needs, but it could be seen as a start in the right direction. As technology
progresses who knows what a small box like that will sound in the future???

 

[lovinthehd]

Yeah prolly wouldn't meet most peoples needs, but it could be seen as a start in the right direction. As technology
progresses who knows what a small box like that will sound in the future???

Unfortunately it's held back by physics of current driver tech in the meantime Could be as small as they're ever going to get on the other hand....

 

[Verdinut]

Yeah prolly wouldn't meet most peoples needs, but it could be seen as a start in the right direction. As technology
progresses who knows what a small box like that will sound in the future???

Technology progresses but the Laws of Physics are inflexible. It is very unlikely that we will be able to obtain infrasonic performance from smaller boxes than at present. IMO, physicists and acoustic specialists have pretty well covered all the possibilities.