Outdoor sub?

[tmurnin]

I’m trying to understand the science behind an outdoor sub, which seems to have become more and more prevalent in the market over the past few years. Since you can’t pressurize an open space, how does an outdoor sub actually work? Or is it just marketing hype that is a waste of $ in real-world use?

 

[ryanosaur]

I can't go into specifics... because I don't know them!
But there are Electronica rigs for large/very large venues that includes subs... spaces that you might not be able to pressurize the way we think of it. What about Pipe Organs, both real and simulated with 32' Stops... that's the low C at 16Hz.
So why can't you reproduce low frequencies outdoors?
Hell, the military has infrasonic weaponry, even! I guarantee it's not meant to be deployed in only a 3000'3 room.
Somebody else will have to answer the how of it, but I accept that they can exist.

 

[lovinthehd]

I use a sub with a wireless transmitter/receiver out on my deck in the summer now and then. Helps a little, but there is boundary reinforcement as well. The kind you bury or disguise as a rock never experienced nor do they appeal for my yard. I've always wondered how many you need to be of much effect....most don't seem to have much capability.

 

[TLS Guy]

I’m trying to understand the science behind an outdoor sub, which seems to have become more and more prevalent in the market over the past few years. Since you can’t pressurize an open space, how does an outdoor sub actually work? Or is it just marketing hype that is a waste of $ in real-world use?

Well it certainly is possible. Unless you live in a remote area then this will be a good way to get your collar felt by the local constabulary.. Once you really do produce low frequencies efficiently, they carry and project for miles without even having to use a lot of power.

The key is, as I so often say you need good coupling, which is not a loudspeaker cone by itself. You need an efficient acoustic transformer. That means a TL or horn sub. No other contenders will do.

 

[highfigh]

I’m trying to understand the science behind an outdoor sub, which seems to have become more and more prevalent in the market over the past few years. Since you can’t pressurize an open space, how does an outdoor sub actually work? Or is it just marketing hype that is a waste of $ in real-world use?

Outdoor subs are sometimes called 'bass bins' and are horn-loaded to increase efficiency (which is related to, but not the same as sensitivity). Sealed boxes would be OK if they're in the corners of an enclosed area, but if you want output, you need horns, lots of them and lots of power. Outdoor audio applications for bass use brute force- this is no place for finesse.

However, companies like Sonance, Episode, Jamo and others have outdoor speaker systems that use an in-ground sub that works very nicely, as long as you aren't trying to recreate Woodstock. OK, bad example- the sound at Woodstock sucked but Milwaukee's Summerfest would be a better example- it was possible to hear too much bass while over 1/2 mile from shore last week when we were on a boat for the fireworks.

Don't worry about 16Hz unless you're actually trying to play synth or pipe organ music with such low frequencies- when the low E string on a bass guitar is plucked, what we hear is generally the first harmonic, at about 82Hz, not the fundamental- because of this and the fact that budgets for outdoor venues are not infinite, they usually HP the FOH sound at around 35Hz-45HZ.

 

[KEW]

I’m trying to understand the science behind an outdoor sub, which seems to have become more and more prevalent in the market over the past few years. Since you can’t pressurize an open space, how does an outdoor sub actually work? Or is it just marketing hype that is a waste of $ in real-world use?

A simplistic way to answer your question is that while you cannot achieve "room pressurization", you can achieve "nearfield pressurization"! As an easy demonstration, if you have two subs inside let them face each other with no more than two feet apart. Lay on your back with your head between them. Play some music, gradually increasing the volume and see where they start sounding like you have achieved all of the pressurization you would ever ask for.
My living room has a lofted ceiling with a balcony, is permanently open to the Kitchen and breakfast nook, office and a large two story foyer. My good (but home consumer) subs cannot pressurize that entire space, but I have very satisfactory bass at my LP. I have 4 subs which average at ~7 feet away (the closest is 4 feet away). This is using sealed 15" subwoofers. I might be able to get away with 2 ported subs if that was my preference!

But much of the outdoor subs are probably "pretend" more than giving you the true subwoofer experience. You either need to get the subs close to your ears or spend money for high dollar specialized products!
Naturally, headphones are often the best option for outdoors - it is easy to just pressurize you ear canal (and maybe 5 cu. in. of "cans")!

 

[tmurnin]

So this would tell me (i think) that for an outdoor sub to make much of a difference in real world application, it would have to be located fairly close to the LP. Since outdoor environments are usually somewhat uncontrolled and designed more for party style listening, that seems impractical and therefore not something on which to spend money. Am I wrong?

 

[DigitalDawn]

Triad has a really nice outdoor sub. It can be mounted either above-ground or below.

https://www.triadspeakers.com/products/everywhere-audio/outdoor/garden-array-ga4-sat-ga10-sub/