Car audio terms, please help?

Question

can you give me the meaning of these words?

sealed

ported

SPL

Answer 1

When choosing a subowofer box, the decision between sealed and ported will determine how the final install will sound. The general rule for this choice is fairly simple.

Sealed subwoofer boxes generally are much smaller than ported enclosures. If you're limited on space, it would probably be a good idea to go with a sealed enclosure. Not only is there a size difference, but there is also a difference in sound between the two enclosures. Sealed enclosures tend to produce tight, accurate bass and have a flat frequency response curve. They are also generally the enclosure of choice when looking for a SQ (Sound Quality) oriented setup.

Ported boxes can get very large and have many varying factors that will determine their size and sound output. Ported enclosures produce louder bass than sealed enclosures, and allow you to tune the box to a specific frequency to determine how the bass will sound. Higher tuning on a ported box will get louder, but at the expense of sound quality. Lower tuning will still get louder than a sealed box, and at the same time will yield fairly good sound quality. For more information on choosing the correct tuning for your ported subwoofer box.

Port area and port type also plays a role in ported enclosures. Too little port area for the subwoofer box can result in port noise, which can severely detract from the sound quality of your setup. To much port area can also have a negative impact on the sound quality. However, if your goal is to get loud and not care about sound quality, then a ported box, tuned high, with a large amount of port area is the way to go.

Personal preference and size limitations will both play a role in the decision between sealed or ported enclosures. If you have the room, and you want to get loud, go with a ported box. If you're limited on space or are looking for the best sound quality possible, it would generally be best to go with a sealed box. Either way, as long as the specifications of the subwoofer box are within the subwoofer manufacturer's recommended box specifications, you should be safe with either choice.

it all depends on what you want to do with the speakers lol..

I have found a closed/sealed is good for rap music. My own oppionon.

Component Speakers

A component loudspeaker is a single driver designed to reproduce frequencies in a given range. Component speakers are used in tandem with other component speakers to reproduce the entire audio spectrum. As few as two and as many as four or more different size drivers can be used to create a component set. The drivers are kept operating within their designed audio band by a series of frequency filters known as a crossover. By using a crossover to keep speakers operating within a certain range the speakers do not become distorted by trying to reproduce frequencies that they are physically unable to reproduce.

In order to keep the point source attribute with a set of component speakers these speakers must be placed very near each other. However this is not always done in practice. Sometimes a midrange/woofer will be placed in a door while the tweeter may be placed in the front corner of the front window (sail panel) or on the pillar that separates the windshield from the door frame (A-pillar). This is done to raise the apparent position of the musicians on an imaginary stage in the front of the vehicle.

It is generally considered desirable to have a sound system that gives the impression that the musicians exist on a stage across the top of the dash, extending beyond the edges of the dash. Raising the tweeter level can help in this goal but other problems occur such as time alignment, the difference in time it takes the low and high frequencies to reach your ears. Ideally all frequencies should arrive at your ears at the same time.

Advantages of this design are generally better sound and more options for installation. Disadvantages are added cost, more complex installation, and possible problems with time alignment.

Aspects and features that need to be considered when purchasing components are:

Frequency Response: This is the how much of the audible spectrum a loudspeaker can reproduce. The value should be given with a rating of +/- some number of decibels, usually three. The greater the frequency range, the better up to 20kHz and down to 20Hz. Realistically a component speaker will not play much below 80Hz. That's why we have subwoofers.

Mounting Depth: This is the distance that a speaker needs behind its mounting surface for its basket and magnet structure. This can be very important when speakers are being installed in the rear deck of automobile that has torsion bars in the trunk or door speakers with window clearance problems.

Power Handling: This is the amount of power a speaker can withstand before failing after a given amount of time. The most important number is the speakers continuous or RMS power handling. Peak power handling means virtually nothing.

Sensitivity: This is a reference measure of how loud a speaker will be with a certain amount of power at a certain distance. The standard is one watt at one meter. By halving the distance an increase of six decibels will be realized and doubling the power will increase the output by another three decibels. This is a trick used by some companies to make their speakers to appear more efficient than they are. Most loudspeakers will be in the ninety decibel range. Keep in mind that a difference of three decibels is equivalent to a doubling of the amplifier power.

A dampening pad reduces outside road noice also helps some raddeling from doors an trunks

Answer 2

Sealed - refers to a enclosure which has no ports, and all the sound comes from the sub itself.  Using this enclosure will give you a tight hard hitting bass that is very controlled.  Also gives you a higher power handeling.

Ported - enclosure that has a port that is a certain length and width inside the box in which sound waves are controlled to come out of.  Produces a much louder, deeper bass, sacrificing a little quality and tightness of bass.

btw a enclosure is the box a sub is in...

SPL - sound pressure level - refers to how much pressure a sub gives off in the cabin of the vehicle, or wherever the sub is installed.  It doesnt just refer to how loud it is, sometimes a sub may sound louder at one frequency played, but actually gives off more pressure at another.  It is measured in decibals.