A Sound Question

[CaptainNemoOfTheNautilusX]

Ahoy Fellow Burners,
We are searching for a sub woofer aboard the good submarine Nauty X to complement two new Mackie 450V2s. The space is finite as it’s a submarine. Ideally we want the absolute smallest unit with the best possible sound. Cost is a concern but the best compact sound quality is the objective. We have shopped some stores and heard a few sales stories and creative demos with intent to always up $ell. Anyone not biased by sales hype and want to share key insights and experience please PM or reply back. Thank you.
Mobilis In Mobili
Nemo

[gyre]

Is this for inside or outside?
What frequency range?
How big is small?
And so on.

I can do a cheap and small sub.
I just need the technology they used to build the Tardis.

I would shoot for the most efficient driver possible and make other compromises from that point, unless you have a waiver on the laws of physics.


Here's a fairly efficient small driver.
Best I know of for the money.
Plenty of choices out there though.

http://www.electrovoice.com/products/300.html

[CaptainNemoOfTheNautilusX]

It is for the inside, looking to install just below one of the Mackies to conserve floor space. We are looking for a completed cabinet type that runs on 110v and is self power. We have a xlr sub feed out of the mixer.

[dragonfly Jafe]

...Here's a fairly efficient small driver.
Best I know of for the money.
Plenty of choices out there though.

http://www.electrovoice.com/products/300.html

Very efficient, but hardly a "SUB" woofer with a 100 Hz F3 spec - this will get loud with very little power, especially when inside a vehicle (ideal for a mutant vehicle), but you will not get any low bass out of it (like the machine throb in welcome to machine by Pink Floyd).

What do you want it for? Loud "mid" bass (like rock-n-roll or other music), or "deep" bass (like sound effects)?

[infinight]

I would go for this sub. Self powered, lots of options, 6 year warranty. Its sounds awesome and has all the crossovers bulit in. Trust me. Were putting one on our car this year and its gonna be amazing!

http://www.planetdj.com/i--HPR151I

[gyre]

They said small.
It's only a 10", but it can be EQed.
I prefer 8" drivers in vehicles myself, even in multiples.

Powered subs aren't my area.
I try to use systems designed with adequate bass to start with.
I use 30" drivers in my home system.

Interesting things have been done with interactive speaker systems that interact with the drivers.
The catch is that you can never change the drivers.

It does depend on your intent.

Here's a few.
http://www.electrovoice.com/products/528.html
http://www.electrovoice.com/products/195.html
http://www.electrovoice.com/products/31.html
http://www.musiciansfriend.com/navigation?q=subwoofers

[gyre]

It sounds like you plan on a single speaker.
If your material is stereo, I strongly recommend stereo bass (even in the same cabinet sometimes).

It matters if your original music is in stereo in that frequency range.
Some music is not engineered that way.

[The Chinese]

[quote="gyre"]It sounds like you plan on a single speaker.
If your material is stereo, I strongly recommend stereo bass (even in the same cabinet sometimes).

It matters if your original music is in stereo in that frequency range.
Some music is not engineered that way.[/quote]

There is no need for stereo bass. Frequencies in the Sub bass region are non directional, and in an enclosed space (which is close to 1/4 space), you would probably just end up with crazy Peaks and valleys in your sub response.

Speaking as a sound engineer almost no music is engineered with stereo sub bass in mind.

[The Chinese]

[quote="gyre"]It sounds like you plan on a single speaker.
If your material is stereo, I strongly recommend stereo bass (even in the same cabinet sometimes).

It matters if your original music is in stereo in that frequency range.
Some music is not engineered that way.[/quote]

There is no need for stereo bass. Frequencies in the Sub bass region are non directional, and in an enclosed space (which is close to 1/4 space), you would probably just end up with crazy Peaks and valleys in your sub response.

Speaking as a sound engineer, almost no music is engineered with stereo sub bass in mind.

[gyre]

There is no need for stereo bass. Frequencies in the Sub bass region are non directional, and in an enclosed space (which is close to 1/4 space), you would probably just end up with crazy Peaks and valleys in your sub response.

Frequencies in the sub bass region are still very directional, which leads to the reason for stereo bass.
It is not driver directionality, a different subject, but typically 60 to 90 degrees.
Most spatial imaging is found in the bass region, rather than the high frequency area.
This is due to the reverberation of low frequency, which defines our sense of space.
Bass is often misunderstood as being omni-directional because it reflects very efficiently off of some surfaces, where higher frequencies would be absorbed.
The wavelengths are very long physically as well.

In an enclosed space too small to form a complete wavelength, you do have compression instead of accurate audio.
This is effectively omni-directional at some frequencies.

But mixing two tracks together electrically, permanently cancels out the original waveforms.
This is worse than the acoustic loss which may occur.
And different.
THX systems recognized this and used to specify stereo subs on stage, even if they were side by side.
They may now content themselves with a different approach.

This loss of information is the reason for discrete sound.
True, no loss if you aren't mixing stereo into mono.
But where true, this is nothing to be proud of.


I didn't address the acoustics of the submarine without having any details as to size, open or enclosed surfaces, materials and so on.

[The Chinese]

Translation:

You don't need stereo Subs ;)

[duffdog]

But mixing two tracks together electrically, permanently cancels out the original waveforms.

Gyre,


Of all the wrong things in that post, this was the wrongest of them all. I spent about 5 minutes deciding which claim was the worst and finally settled on this one. Though, the one about 60 to 90 degree directionality was a close second.

To the OP -- strangely enough, the most bass you can get out of the smallest footprint is a bandpass sub. Mackie makes several versions which may suit your needs.

[gyre]

But mixing two tracks together electrically, permanently cancels out the original waveforms.

Gyre,


Of all the wrong things in that post, this was the wrongest of them all. I spent about 5 minutes deciding which claim was the worst and finally settled on this one. Though, the one about 60 to 90 degree directionality was a close second.

To the OP -- strangely enough, the most bass you can get out of the smallest footprint is a bandpass sub. Mackie makes several versions which may suit your needs.

Alter would be technically more accurate than "cancels".
But there is information lost.

The directionality figures come from several driver manufacturer's technical sheets.


Air Force research indicates that hearing is direction sensitive in three dimensions.
They are trying to use this to provide pilot information.

But when the volume is high enough to overload hearing, these more subtle issues may no longer matter.
Decide for yourself.

[The Chinese]

But mixing two tracks together electrically, permanently cancels out the original waveforms.

Gyre,


Of all the wrong things in that post, this was the wrongest of them all. I spent about 5 minutes deciding which claim was the worst and finally settled on this one. Though, the one about 60 to 90 degree directionality was a close second.

To the OP -- strangely enough, the most bass you can get out of the smallest footprint is a bandpass sub. Mackie makes several versions which may suit your needs.

Alter would be technically more accurate than "cancels".
But there is information lost.

The directionality figures come from several driver manufacturer's technical sheets.


Air Force research indicates that hearing is direction sensitive in three dimensions.
They are trying to use this to provide pilot information.

But when the volume is high enough to overload hearing, these more subtle issues may no longer matter.
Decide for yourself.

Put a 40Hz tone sine wave up on a pair of speakers. a Stereo pair. sit in the sweet spot, and turn the volume to about 70dBc. Tell me where the signal is coming from.

Now Put the same test tone in both speakers. In a double blin test, have another engineer move pan knob 10 deg in either direction, see how accurate you are in telling which way it goes.

Now, If you are postulating that some artist may put a Stereo bass track or set of tracks in their music, well OK. That's certainly possible. But in the scenario that the OP put forth there is simply Zero need for a stereo Playback system for the Subs.

[duffdog]

But mixing two tracks together electrically, permanently cancels out the original waveforms.

Gyre,


Of all the wrong things in that post, this was the wrongest of them all. I spent about 5 minutes deciding which claim was the worst and finally settled on this one. Though, the one about 60 to 90 degree directionality was a close second.

To the OP -- strangely enough, the most bass you can get out of the smallest footprint is a bandpass sub. Mackie makes several versions which may suit your needs.

Alter would be technically more accurate than "cancels".
But there is information lost.

The directionality figures come from several driver manufacturer's technical sheets.


Air Force research indicates that hearing is direction sensitive in three dimensions.
They are trying to use this to provide pilot information.

But when the volume is high enough to overload hearing, these more subtle issues may no longer matter.
Decide for yourself.

At one point in my life, I used to care about acoustic engineering, sound propagation and electronic sound measurement techniques. Then, I decided that it was pointless to care at all. Recently I have found that the less I care about audio in general, the more money and sex I get.

[dragonfly Jafe]

Decide how much space you have for a cabinet (internal space, the air volume inside your cabinet). Then look for a speaker with a Vas that is close to this. Wire the speaker(s) and mount them. Play music, enjoy.

Within your vehicle, almost any bass driver will give you good results as long as you size the cabinet accordingly. You can be off a little and not really notice it.

When selecting a driver, there is a trade-off between efficiency (SPL/watt) and low frequency capability. Decide if you want to play the mid-upper bass range REALLY LOUD, or if you want the ability to generate LOW FREQUENCY bass (below 40hz say). Note: most music bass is above 40 hz, unless you are playing synthesized sounds you are unlikely to need a low frequency system.

Now that you have made the decision above, if you decided on REALLY LOUD sound, then you want the highest SPL/watt @ 1 meter rating (high 90's or even 100 or above are possible) for your given cabinet size (Vas). This speaker will put out loud bass for very few watts, making it the best choice for battery powered systems. It will NOT generate loud low bass (below 40hz). If you decided on LOW FREQUENCY bass, then you want the lowest F3 rating for your Vas. Such speakers typically have efficiency ratings of 88-92 dB SPL / Watt.

Most burners would probably do fine with REALLY LOUD speakers, and they are often cheaper (due to smaller magnets, etc).

Good Luck! If you already have an 8" or 10" or 12" woofer, give that a shot. It really is not rocket science.

[Diverse]

Ohh awsome, its gonna be so rockin in there with a nice sub for the low, low.
Hope you are able to find a good one.

[Elorrum]

anyone tried bass transducers? low low, and small

[krisstradley]

It seems odd to me that people dont use car audio 12v for art cars. You already have a power source (the car) and large amounts of sound can be produced. My camp runs its sound system and all our lights off some 12v batterys and a wind-gen. Build a dance floor with the sub under it. If you are looking to do this sort of project someone you know has a huge 12-15in sub and 1000 watt amp in the back of their honda. If not, get one. I'm guessing it will still be less than what you are planning on spending for a 110v sub. Do the research on how to build the box. It may be a good idea to run a second battery near the amp.

[CaptainNemoOfTheNautilusX]

The Nautilus and many larger vehicles use a 24v system. While voltage converters are available they are pretty cost prohibitive. Also we have a generator installed which runs 110v. Since I started this topic we purchased a Cerwin Vega 18" and its awesome! The enter vehicle reverberates all over the storage yard. All of you are invited to please stop by and enjoy some groovy sounds while we tour the art. Listen for the ping.

[CaptainNemoOfTheNautilusX]

The new Nautilus sound system worked out remarkably well at this years burn! Thank you again for all of your advice, hope each of you had a really great time too!