Kind of quiet around here...

[BuyOtherSoundEquipment]

So I'll take this time to pose a sort of open-ended question.

It's fair to say that I have little experience with high-quality subwoofers. The "best" I experience on a daily basis (working at Best Buy) would be something along the lines of a Rockford Fosgate P3 or Alpine Type R 12" (which, on their website, lists a freqency response of 25hz to 500khz hehe). Those drivers are extremely boomy and cannot even begin to delve into any material below 24hz, and any (other) fool who works there will tell you that they are the "best of the best" for subs. For a while, I myself percieved that all subwoofers performed this way and that even the best units would behave likewise.

I had my eyes opened when I attended the 08' pilgrimage in Indy, where I heard a demo of the Palladium P-312W on the song "Ain't Yo Bidness" by the Insane Clown Posse. Throughout the song, there is a low sweep of bass, one tone at what I assume is around 24 hz and one that is lower (18hz?). The P-312W shook the room authoritatively on the first wave and then, the part that really made an impression on me, made the air in the room (and also my pant legs) quiver with a subsonic rumble on the lower tone. This was probably one of the most impressive single experience that I took away from those demos.

I'm not saying that that particular song is anything great (kind of annoying, really) or that it is great quality, but the bass characteristics I heard (and felt) changed my thinking on subs.

I said all that to ask this: What (really) separates a good quality subwoofer driver from a mediocre one? I see models and brands listed every day but that doesn't cut it for me. I know I'm preaching to the choir here, but I hear claim after claim everywhere that such-and-such driver is superior and on and on. I'm seeking the keys to such claims and how to distinguish real performance from [bs].

I leave the question at that, but on a more specific note, where would the eD A7S-450 fall in a determination of performance? I ask that because it is my #1 candidate for my own sub. Is it really capable of pant-quivering, 14hz-18hz bass like the Palladium sub? Help me out here!

[TheEAR]

A great subwoofer driver will remain linear in the Xmax (BL curve here),a great sub driver will add little mechanical noise(all drivers add more or less). A great sub driver will have Xmax of over 20mm and the upper class is in the 30mm one way,the best units range from 38-around 50mm ONE WAY(note displacement is not an indicator of quality,not at all).

Quality sub driver often have BL hoovering 15-30. The higher the BL the smaller the optimal box will be.Very low BL ~10 is fine when you look for "free air" or IB drivers.Here the back pressure is equal to the pressure in front of the driver. No need of high BL andpowerful motors.

...have to work now. At work...

I am sure more will chime in. I could go on and on for pages but that will be it...work...

[Ricci]

In addition to what Arthur posted a good subwoofer possesses the following.

Large displacement capability. Low bass requires this. This is related to cone area and xmax. However many mfg xmax claims are overstated. Linearity is also key. A strong suspension system that will control and center the cone and also help provide protection from bottoming. A good cooling system with a large vc to help keep power compression down and allow the driver to handle large amounts of power. A robust and overbuilt construction to withstand heavy use. A moderate to low inductance is considered key by many to allow a smoother upper bass response and transition to the other speakers. There are quite a few tricks employed to this end. The most common is probably a copper sleeve in the pole. There are also many different vc techniques used to help maintain linearity and lower distortion. XBL^2, LMT, split coil, etc. Traditional overhung and underhung designs can work fine too.

In short. The driver should be low distortion, high displacement, linear, high power handling, low self noise, rugged, versatile, low inductance, reasonably efficient and might as well be good looking too.

You also need to determine what your needs are as some drivers are not well suited to certain applications. Many high power small sealed box drivers are not well suited to porting because the port needed will not be feasible. Example: Audiopulse Axis 15. Other drivers are great for very large HT ported subs, but will not be so great in a relatively small high powered sealed app. Example: Fi caraudio SSD 18. Not all drivers are suited for horn loaded apps. Some drivers are versatile and can be used in many different alignments quite well. Example CSS SDX 15. This driver does well in large low tuned ported, smaller ported, small and larger sealed, PR'd, etc.

Figure out what you need the system to do and how much room and finances are available to do it. Then pick a quality driver that is well suited to the task. There is no "best" driver though some may say that there is. There may be a best driver for the intended application though.[8-|].

You were looking at the A7S-450. I don't have direct experience with it so I can't say anything concretely about it. How much is that guy? You may also want to look at the Epik Caliber, or if you can afford a bit more the Tower. They should have more output than the ED in the low bass 14-25hz.

When looking at commercial subwoofers a bigger cabinet and driver is the recipe for more bass.

[BuyOtherSoundEquipment]

Thanks for the input, Ricci.

The eD A7S-450 is $775 base, add $85 for eQ.2, another $85 for the LT1300 amp. I had a chat discussion with one other their techs, and he said that due to my room size (12 x 13.5 x 7.5) I should have tremendous room gain (makes sense).

eD ships for free, too. That would add about $150 to any sub from epik.

[Ricci]

No problem.

So it's about $945 for the ED. I'd still consider an Epik Caliber which would be about $100 cheaper, or one of the other Epiks. An AV123 MFW-15 would be something to look at also. It'd look a lot better. I just think that the Epik's and the MFW-15 are a bit better designed and built. I have no personal experience with any of them though, so I'm just going off of hear say and my gut. That is a small room I'm sure that any of the 3 will rock the house.