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Whats the difference between

Guest bob33

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>Acoustic suspension speakers and just regular old speakers is

>this because the cabnet is sealed. Im confused.

Hi there;

There is much more advice than I can give you coming, after your topic is read.

Edgar Vilchur, of Acoustic Research fame, invented and produced the first commercial acoustic suspension speaker principles back in the '50's.

A very smart man, years ahead of his time.

He convinced his draughtperson wife to cut out the first surrounds from their bedding sheets.

Could you imagine if she had come home from shopping, and found 12" holes cut in all of their bedding.

Prior to this you needed a refrigerator sized enclosure to ensure deep bass.

Also that was pre-stereo days, so that you only needed one, thank goodness.

With the acoustic suspension, the surround is soft and cone is supported by the mass of air within the sealed enclosure.

Deep, clean, un-distorted bass could now be obtained in a smaller enclosure, ( if you consider an AR-1W bookshelf speaker at about 50 pounds, small ) and if you had a decent power amplifier.

There is much written on the various types of systems.

There is probably 12 different type of systems and 12 subsystems of them and hybrids.

Each has their supporters and detractors.

Acoustic suspension speakers, does not guarantee you the most perfect bass, but usually compactness and deep, stomach churning bass.

If the driver was not designed for acoustic suspension, then the end result will be less than desirable.

Very good question, more information to follow, by others, I am sure.

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>Acoustic suspension speakers and just regular old speakers is

>this because the cabnet is sealed. Im confused.

There is much more to it than just sealing the box.

People who made speakers knew for decades that they needed to deal with the problem of the sound coming from the back of a speaker re-emerging to coincide with the sound coming from the front of the speaker because with no enclosure, these two waves meet out of phase and cancel each other out. Take any speaker, even one from a table radio and without an enclosure, you will hear very little bass. Many ideas have been devised to deal with this problem and the one most commonly used in the mid 1950s was the bass reflex design. Inside the box, the back wave hits the back of the box and the phase of the sound is inverted to emerge from an opening in the front in phase reinforcing rather than cancelling the back wave. But it is very frequency dependent and to achieve very low bass, you need a very big box. Same problem for horn speakers, to get deep bass, you need a huge enclosure. Even the largest speakers of these types cannot produce much of the lowest audible octave. That's the physics of it which hasn't changed.

Enter Edgar Vilchur in the mid 1950s who came along with a new and better idea. Not only did he trap the back wave inside which is the theory behind the much larger infinite baffle concept (imagine a brick wall of infinite size preventing the back wave from ever emerging) but instead of the stiff corrugated surrounds used to restore the cone to its nominal neutral position after each half cycle of vibration, he made the suspension very very very loose and allowed the springiness of the air trapped inside to do the work instead. This is a very linear non frequency dependent restoring force. The box wasn't made small as a goal but as a necessity so as not to have too much air or it wouldn't provide the springiness to restore the cone. Then it was a matter of tuning the system by arranging the moving mass and the damping supplied by internal stuffing material (probably originally fiberglass) to create a system which is critically damped (no spurious vibrations) at a very low frequency, in the case of AR1, AR3, and AR3a at 42 hz. The driver has an inherent resonant frequency of around 16 hz but in the enclosure, it is 3 db down at 42 hz. Remarkably, it has usable output to 30 hz or below where it has a mere 5% harmonic distortion. To this day 50 years later, few loudspeaker systems can match it. So the principle is that the air trapped inside the box provides the restoring force to the cone, not the mechanical stiffness of the driver suspension itself. This is what distinguishes a true acoustic suspension speaker system from other types of speaker systems.

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Oh i got it that sound cool in your opinion what sounds better acoustic suspension or vented speakers? I like acoustic suspension but my dad owns a pair of jbl l112s Those are vented and sound awsome it all depends on what kind of speaker you are looking at i guess.

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>Oh i got it that sound cool in your opinion what sounds

>better acoustic suspension or vented speakers? I like acoustic

>suspension but my dad owns a pair of jbl l112s Those are

>vented and sound awsome it all depends on what kind of speaker

>you are looking at i guess.

I look for speakers that reproduce recordings of acoustic instruments with the same tone (timbre) as the actual instruments themselves. This is what the term high fidelity means to me and is the only way I know to validly judge performance of speakers. The best acoustic suspension speakers have invariably sounded better to me than other types insofar as their ability to reproduce the lowest octaves of bass notes musically. I have not shopped for speakers for many years so I haven't compared the latest offerings from the best vented designs. I have noticed that many of the best subwoofers today appear to be acoustic suspension designs though. This of course does not speak to the rest of the audible range. Many speakers which appear to produce considerable bass actually have a peak in the upper bass but when you listen to something really challenging like a pipe organ, there is little or nothing of real substance. The illusion of bass from this type of peak eventually becomes a tiresome droning unmusical sound which is more annoying than anything else. Perhaps this is why so many "audiophile speakers" have little or no bass at all. I think it is also outrageous for a manufacturer to ask thousands of dollars for a pair of supposedly high fidelity loudspeakers and then tell you that if you want to hear the lowest octave, you have to spend another thousand or more on a separate subwoofer. Most live music contains a surprisingly large amount of bass, far more than most home sound systems can or do reproduce.

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