Bass tubes
Guest
Posts: n/a
the physics of the egg shaped enclosure, or more so the physics behind the way the sound waves move in one... but, like you said, its hard to get an egg shape perfect.
The only rough part about the infinite baffel in the doors would be sealing one side of the sub/mid from the other. but if you were to lock the window "up" and seal below it, I dont think it would be too tough. But keeping window functionality would be the hard part.
And maybe its just the way we tuned the tubes, but if we tuned to say 32hz, we would kill frequencies on the top end. Not tuning always seemed to cause waves to cancel each other out. when we built them, we used that "bendable plywood" then fiberglass resin to seal it.so maybe that has something to do with it? All the SQ enclosures I have seen take a comp have been small volume sealed enclosures built to manufacturer specs. I dont think I have ever seen a bazooka abs tube take a comp. I have seen cylinders place high, but when I hear "bass tube" I see Bazooka tube or some nitrous bottle looking enclosure.
The only rough part about the infinite baffel in the doors would be sealing one side of the sub/mid from the other. but if you were to lock the window "up" and seal below it, I dont think it would be too tough. But keeping window functionality would be the hard part.
And maybe its just the way we tuned the tubes, but if we tuned to say 32hz, we would kill frequencies on the top end. Not tuning always seemed to cause waves to cancel each other out. when we built them, we used that "bendable plywood" then fiberglass resin to seal it.so maybe that has something to do with it? All the SQ enclosures I have seen take a comp have been small volume sealed enclosures built to manufacturer specs. I dont think I have ever seen a bazooka abs tube take a comp. I have seen cylinders place high, but when I hear "bass tube" I see Bazooka tube or some nitrous bottle looking enclosure.
Last edited by ericemery; Sep 23, 2010 at 10:31 AM.
Veteran
Joined: Sep 2010
Posts: 294
Likes: 0
I don't think you completly understand how infinite baffle subs work. The window, being open or closed would have no bearing on the IB sub. The only difference with the window open or closed would be that the window takes up a small amount of volume in the door iteself that changes the "enclosure" size.
Thew biggest thing that the window being open or closed changes is the size of the enclosure that the speaker is playing ito, that happens to be the same space that the listener is sitting in. This is the same effect as when the windows are open or closed using any type of enclosure.
Taking IB one step farther and my favorite enclosure I have ever built is changing it into an Aperiodic enclosure, that is likely how a sub installed in a door would likely work best. Just takes a lot of power to play loudly.
You must be doing something wrong with these tubes, you should notice the same effect with any shape enclosure. The volume of the enclosures will give a "tuned frequency", whether it is ported, sealed or otherwise. The volume of the enclosure needs to be matched to the port tuning frequency, within reason, to work best.
Do some more research on how tuning ported enclosures changes the overall responce of an enclosure. Looking at graphs created something like Bas Box Pro 6, and playing with tuned frequincies can illistrate this well, when the center frequicies are moved.
Besides, who wants any frequencies higher than about 65Hz playing through thier subs?
I made tubes from cardboard construction tubes, and have fibreglassed them, and even, left them just the thin cardboard, and they sounded the same with or without the fibreglass. It seemed that once the end plates were added, they increased the strength enough to not need the 'glass.
Thew biggest thing that the window being open or closed changes is the size of the enclosure that the speaker is playing ito, that happens to be the same space that the listener is sitting in. This is the same effect as when the windows are open or closed using any type of enclosure.
Taking IB one step farther and my favorite enclosure I have ever built is changing it into an Aperiodic enclosure, that is likely how a sub installed in a door would likely work best. Just takes a lot of power to play loudly.
You must be doing something wrong with these tubes, you should notice the same effect with any shape enclosure. The volume of the enclosures will give a "tuned frequency", whether it is ported, sealed or otherwise. The volume of the enclosure needs to be matched to the port tuning frequency, within reason, to work best.
Do some more research on how tuning ported enclosures changes the overall responce of an enclosure. Looking at graphs created something like Bas Box Pro 6, and playing with tuned frequincies can illistrate this well, when the center frequicies are moved.
Besides, who wants any frequencies higher than about 65Hz playing through thier subs?
I made tubes from cardboard construction tubes, and have fibreglassed them, and even, left them just the thin cardboard, and they sounded the same with or without the fibreglass. It seemed that once the end plates were added, they increased the strength enough to not need the 'glass.
Thread Starter
|
Champion
Joined: Feb 2010
Posts: 3,686
Likes: 0
From: Greenfield, Wisconsin
I don't think you completly understand how infinite baffle subs work. The window, being open or closed would have no bearing on the IB sub. The only difference with the window open or closed would be that the window takes up a small amount of volume in the door iteself that changes the "enclosure" size.
The rear windows go down all the way in these trucks, which takes up a lot of that door. If you want that window to roll down, you arent going to have much space.
Veteran
Joined: Aug 2009
Posts: 271
Likes: 0
From: Bluefield, WV
Is this what you used Ueland?
http://www.hifisoundconnection.com/S...id/0/SFV/30046
Just to make sure, this will allow me to keep the speakers in my doors powered by my factory head unit, and give me (a few too many) low level outs for a subwoofer?
http://www.hifisoundconnection.com/S...id/0/SFV/30046
Just to make sure, this will allow me to keep the speakers in my doors powered by my factory head unit, and give me (a few too many) low level outs for a subwoofer?
I'm also running one of these which I mounted in the little pocket next to the cigarette lighter
http://www.hifisoundconnection.com/S...id/0/SFV/30046
It gives me the instant ability to tune the amp up or down without affecting the rest of the speaker bass levels.
Veteran
Joined: Sep 2010
Posts: 294
Likes: 0
I think Eric was talking about the enclosure size and actually making it big enough while still keeping the window functional.
The rear windows go down all the way in these trucks, which takes up a lot of that door. If you want that window to roll down, you arent going to have much space.
The rear windows go down all the way in these trucks, which takes up a lot of that door. If you want that window to roll down, you arent going to have much space.
Uh huh...
Look up what an "Infinate baffle speaker" is, then you'll understand why the window position has no bearing on getting it to work.
Veteran
Joined: Aug 2009
Posts: 271
Likes: 0
From: Bluefield, WV
As for the discussion on which enclosure style is better tube, egg, bandpass infinite baffle, I'll say which ever reflects the least amount of unwanted waveforms back at the speaker would be the most optimal choice. actually a nautilus shell is a very perfect speaker box design but very expensive and dificult to produce, not to mention the space limitations of a mobile installation that would make it near impossible to use.
To the concept of using "manufacture box specs" for building a box, for general applications thats fine, however doing your OWN calculations using Theile/Small is the only way to go to get the most precise/efficent design for a specific aplication.
http://en.wikipedia.org/wiki/Thiele/Small
To the concept of using "manufacture box specs" for building a box, for general applications thats fine, however doing your OWN calculations using Theile/Small is the only way to go to get the most precise/efficent design for a specific aplication.
http://en.wikipedia.org/wiki/Thiele/Small
Registered User
Joined: Sep 2010
Posts: 5
Likes: 0
From: Texas
Sometimes the loss of bass is do to the fact the speakers are out of phase. Usually the factory speaker connectors will not work on aftermarket speakers, so unless you use adapters, it is possible to get the wires on the wrong terminal on the speaker. Basically, you've got the positive on one terminal on one speaker, & the opposite terminal on the other speaker, which makes them out of phase.
As far as a good deal on a sub & amp, Crutchfield.com. I bought a 500 watt Blaupunkt 2 channel for $99, and a 8 in sub tube for $129 for my Jeep. Plenty of bass.
As far as a good deal on a sub & amp, Crutchfield.com. I bought a 500 watt Blaupunkt 2 channel for $99, and a 8 in sub tube for $129 for my Jeep. Plenty of bass.
Veteran
Joined: Sep 2010
Posts: 294
Likes: 0
Sometimes the loss of bass is do to the fact the speakers are out of phase. Usually the factory speaker connectors will not work on aftermarket speakers, so unless you use adapters, it is possible to get the wires on the wrong terminal on the speaker. Basically, you've got the positive on one terminal on one speaker, & the opposite terminal on the other speaker, which makes them out of phase.
As far as a good deal on a sub & amp, Crutchfield.com. I bought a 500 watt Blaupunkt 2 channel for $99, and a 8 in sub tube for $129 for my Jeep. Plenty of bass.
As far as a good deal on a sub & amp, Crutchfield.com. I bought a 500 watt Blaupunkt 2 channel for $99, and a 8 in sub tube for $129 for my Jeep. Plenty of bass.
I'm just going to correct you on this, and it's something that most people do, I even did it for years until I trained myself not to.
What you are refering to is actually "out of polarity". Being out of polarity does not mean that a speaker is out of phase.
Polarity refers to electrical properties.
Phase refers to a time based property.
It is completely possible, and I have done this on several occasions, to have a speaker out of polarity but in phase, with other speakers.
Relative positioning of speakers has a large effect on the phasing of speakers.
To keep it simple, when two speakers are in phase, the peaks of the sine waves created by those speakers are arriving at your ears at the same time. When speakers are out of phase you are receiving a peak and a valley at the same time, that cancels each out. Since it takes time for sound to travel from the speaker to your ears, positioning of the speakers can change the phasing, without changing the polarity.
Last edited by Six_Shooter; Sep 25, 2010 at 12:01 PM.
Champion
Joined: Aug 2009
Posts: 3,971
Likes: 91
From: Jersey
Bazooka Power!!! I had this 8" amplified bazooka tube in the trunk of a convertible some years back. This thing really put some nice bass into my system. I plan on using a quick disconnect and it fits perfectly on the floor behind the drivers seat in my Dakota.
100_1125.jpg
100_1125.jpg
