sealed or ported enclosure?? (vote)
08-20-2005 | 05:36 PM
#22
Ported for me
http://www.obso.net/tunes/IMG_0076.JPG
As you can tell from the link, I'm a fan of the ported box
From my own experience and opinion, Yes Ported boxes can great crazy loud, but are do they sound better? thats up to you, do you want sloppy or tight bass. The ported boxes will more than likely hit lower, but the sealed boxes will hit harder. Put that L7 in a ported box. and Remember, Play it loud, dont play it stupid 
As you can tell from the link, I'm a fan of the ported box
From my own experience and opinion, Yes Ported boxes can great crazy loud, but are do they sound better? thats up to you, do you want sloppy or tight bass. The ported boxes will more than likely hit lower, but the sealed boxes will hit harder. Put that L7 in a ported box. and Remember, Play it loud, dont play it stupid
08-23-2005 | 03:24 AM
#23
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You can tune a ported box to be as loud or as musical as you want. You can completely eliminate port noise through the use of slot ports, and flared ports. You can tune a ported box to extend very low, but at the sacrifice of power handling. Or tune it to win SPL competitions. A ported box requires less power.
Overall, for 90% of people, a sealed box will get 'er done. You'll go just a low based on the car's interior transfer function, and only lose 3db vs a ported box. 3db's is not audible to the human ear.
Not to mention a sealed box is easier to build, is less forgiving to mistakes in volume and port mis-calculations, and is smaller in size. Those qualities alone make them perfect for most any enthusiast.
[Yoda speak] Specific SPL goals you have, then ported build you must. [/yoda speak]
Overall, for 90% of people, a sealed box will get 'er done. You'll go just a low based on the car's interior transfer function, and only lose 3db vs a ported box. 3db's is not audible to the human ear.
Not to mention a sealed box is easier to build, is less forgiving to mistakes in volume and port mis-calculations, and is smaller in size. Those qualities alone make them perfect for most any enthusiast.
[Yoda speak] Specific SPL goals you have, then ported build you must. [/yoda speak]
08-24-2005 | 02:14 PM
#24
You post this:
Originally Posted by unredeemed
So much mis-information in this thread 
Originally Posted by unredeemed
3db's is not audible to the human ear.
Maybe this page will shed a little more light on the subject of decibels for you. http://www.phys.unsw.edu.au/~jw/dB.html
Be sure to go down to the first example under "Sound files to show the size of a decibel" then tell me 3dB isnt distinguisable in volume to the human ear.
08-24-2005 | 03:49 PM
#25
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Put something in a reference environment and sure. Take a car with so many other outside noise and interference, umm think again.
This is not a debate on physics. This is real world, and 3db's is nothing.
This is not a debate on physics. This is real world, and 3db's is nothing.
08-24-2005 | 04:31 PM
#26
Originally Posted by unredeemed
(3db's is not audible to the human ear)
Could be true or false. It depends on were on the scale you are changing the 3db. If change 3db any were between 0db and 60db you wont be able to tell the difference. The higher you get up the db scale the more the sound gets louder.
What makes a sound quiet or loud? The answer is the degree to which the air molecules in the sound wave are either compressed or rarefied. This measurement is called amplitude. A loud sound is one in which there is a high degree of compression or rarefaction and thus the eardrum vibrates more violently. The unit of measure used to measure the intensity or loudness of a sound heard by the ear is the decibel. It is a ratio of the pressure of the sound wave at the ear to the pressure of the standard sound. That standard sound is one that is just below the level of hearing for a healthy young person and is called the threshold of hearing. It is rated at 0 decibels. The scale of decibel is not an arithmetic progression but a logarithmic one. The human ear begins to hear at very low decibels and hears sounds more clearly as the decibel level rises. The impact of sound on the ear, however, does not increase directly with the increase of the decibels. The hearing difference between 0 and 65 decibels, a 65 decibel spread, ranges up from silent to normal conversation; however, the hearing difference between 65 and 95 decibels is only a 30 decibel spread brings us from normal conversation to the loudness of a punch press or a pneumatic jack hammer. At 120 decibels the threshold of pain occurs. Above 120 decibels sound is damaging to us. Even in the 90 to 120 decibel range extended exposure can be harmful. At 110 decibels, 20 more, the exposure limit is cut drastically to only ˝ hour per day. To complete this brief discussion of a decibel, the decibel reading of noise in a given environment can be the pressure ratio on the ear of all the frequencies present combined and this is usually the case as we rarely hear pure sound. Decibels, abbreviated as dB, are often expressed in combination with a letter, such as A, B or C. These indicate various methods of measuring decibels called weighing scales. The most common is dBA. The “A” weighing scale is an electrical model of the human ear, which doesn’t hear well below 1000 cycles per second (hertz) or above 4,000 cycles per second. The dBA scale is thus most useful in purposes dealing with audible sound and its control.
(3db's is not audible to the human ear)
Could be true or false. It depends on were on the scale you are changing the 3db. If change 3db any were between 0db and 60db you wont be able to tell the difference. The higher you get up the db scale the more the sound gets louder.
What makes a sound quiet or loud? The answer is the degree to which the air molecules in the sound wave are either compressed or rarefied. This measurement is called amplitude. A loud sound is one in which there is a high degree of compression or rarefaction and thus the eardrum vibrates more violently. The unit of measure used to measure the intensity or loudness of a sound heard by the ear is the decibel. It is a ratio of the pressure of the sound wave at the ear to the pressure of the standard sound. That standard sound is one that is just below the level of hearing for a healthy young person and is called the threshold of hearing. It is rated at 0 decibels. The scale of decibel is not an arithmetic progression but a logarithmic one. The human ear begins to hear at very low decibels and hears sounds more clearly as the decibel level rises. The impact of sound on the ear, however, does not increase directly with the increase of the decibels. The hearing difference between 0 and 65 decibels, a 65 decibel spread, ranges up from silent to normal conversation; however, the hearing difference between 65 and 95 decibels is only a 30 decibel spread brings us from normal conversation to the loudness of a punch press or a pneumatic jack hammer. At 120 decibels the threshold of pain occurs. Above 120 decibels sound is damaging to us. Even in the 90 to 120 decibel range extended exposure can be harmful. At 110 decibels, 20 more, the exposure limit is cut drastically to only ˝ hour per day. To complete this brief discussion of a decibel, the decibel reading of noise in a given environment can be the pressure ratio on the ear of all the frequencies present combined and this is usually the case as we rarely hear pure sound. Decibels, abbreviated as dB, are often expressed in combination with a letter, such as A, B or C. These indicate various methods of measuring decibels called weighing scales. The most common is dBA. The “A” weighing scale is an electrical model of the human ear, which doesn’t hear well below 1000 cycles per second (hertz) or above 4,000 cycles per second. The dBA scale is thus most useful in purposes dealing with audible sound and its control.
08-24-2005 | 11:39 PM
#27
I agree with both of your rebuttles to an extent but the general statemet '3dB is not audible to the human ear' is completely false. That was the point I was tring to make.
OK, now back to original programming.
OK, now back to original programming.
I Now Need To Dyno Mat My Cab. But Its Sounds Really Good.
09-05-2005 | 02:43 PM
#30
There are arguments here which have been made, but these are our personal observations. Sound is a subjective thing. What I think sounds good may not to someone else. What you should be concentrating on is what type of sound are you after? Do you want to have really tight bass - very snappy snare drums? Do you want very loud low-frequencies (rap/hip-hop music)? Unredeemed is accurate with his descriptions. I agree that a properly designed and built ported loudspeaker enclosure plays very melodically, but is more complicated to design and build (for the novice). A sealed enclosure is easier to build, but will not extract the most power (efficiency of the enclosure.....whole different thread) from the combination.
The argument about not being able to hear 3dB difference....I can tell you that at 165+dB, you cannot tell the difference between the two without a calibrated meter (pcRTA, b&k). At 80dB, only those who study acoustics can tell readily, and that is with an A / B test (listen to 80dB, then 83dB). I have been involved in car audio for over 15 years now....from installing SQ systems to building a Record-setting SPL vehicle and competing with it from 1997-1999. I have had a hand in 4 more SPL vehicles, and am working on another vehicle that will 'turn some heads' when it hits the competing scene.
....and one more note about ported boxes and their accuracy potential.....if the argument is made that a ported enclosure is not as accurate as a sealed enclosure, then how can you explain transmission-line enclosures? How about Helmholts resonators? Horns?
Typhoon #1600
a.k.a. QBNBASS
PS...PORTED ALL THE WAY!! Sealed is 'old-school' SPL!
'Scotty! All ***** to the right!'
The argument about not being able to hear 3dB difference....I can tell you that at 165+dB, you cannot tell the difference between the two without a calibrated meter (pcRTA, b&k). At 80dB, only those who study acoustics can tell readily, and that is with an A / B test (listen to 80dB, then 83dB). I have been involved in car audio for over 15 years now....from installing SQ systems to building a Record-setting SPL vehicle and competing with it from 1997-1999. I have had a hand in 4 more SPL vehicles, and am working on another vehicle that will 'turn some heads' when it hits the competing scene.
....and one more note about ported boxes and their accuracy potential.....if the argument is made that a ported enclosure is not as accurate as a sealed enclosure, then how can you explain transmission-line enclosures? How about Helmholts resonators? Horns?
Typhoon #1600
a.k.a. QBNBASS
PS...PORTED ALL THE WAY!! Sealed is 'old-school' SPL!
'Scotty! All ***** to the right!'