Who makes the lowest distortion pro-sound subwoofers?

[thadman]

As is the situation with the 18sound midrange drivers, I haven't been able to track down much information regarding prosound subwoofers.

Who makes the lowest distortion prosound subwoofers? As far as alignment, lets say Infinite Baffle or LT.

The only high performance drivers that I'm aware of that may possibly be given this title are the BMS 18N850, 18Sound 21LW1400, or PD2150/PD2450. What other options are available?

[garage1217]

Aura 1808 IMO

[Tim__x]

If low distortion is your primary goal, besides picking fundamentally low distortion woofers (an admirable choice to be sure), you should look at your design choices and see what you can do.

Try to keep excursion down, that means more and larger drivers. Horn loading is a terrific choice for low distortion. If you're feeling truely brave you might look into closed loop systems with servo feedback.

[thadman]

Infinite Baffle or Linkwitz Transform (10hz) would be the desired alignment. Since Prosound woofers come in sizes up to 24", 120dB at 10hz-100hz seems like a perfectly acceptable challenge with boundary gain included and >2 subwoofers.

10hz would be just a challenge. If they had the displacement capability to drop down to 10hz, then 20hz transients would be a walk in the park. It would also be quite impressive imo.

High pass filter would be adjustable for Output levels desired. For instance:
U571, hpf at 10hz (think 48-96dB/octave)
mundane HT, hpf at 15-20hz
music, hpf at 30hz

If possible, I'd like to keep cost below $2000-2500.

[Eva]

Infinite baffle and Linkwitz Transform are the alignments demanding the highest cone displacement for a given SPL and thus they are the ones producing the highest distortion levels, like 10% THD at 40Hz when trying to make it a bit loud.

For low distortion (in that sense) consider horns, they can be designed to produce some low frequecy SPL with little cone displacement.

[lne937s]

It seems to me that there is some confusion between dipole and infinite baffle. Infinite baffle presurizes the room and uses the room behind the baffle like an infinitely large box. Dipole does not pressuize the room- with both the front and rear waves being emitted into the same room. Infinite baffle has efficiency like a really large sealed cabinet. Dipole is the most demanding of displacement/excursion- making it difficult to get high spl at low frequencies.

[thadman]

Originally posted by lne937s
It seems to me that there is some confusion between dipole and infinite baffle. Infinite baffle presurizes the room and uses the room behind the baffle like an infinitely large box. Dipole does not pressuize the room- with both the front and rear waves being emitted into the same room. Infinite baffle has efficiency like a really large sealed cabinet. Dipole is the most demanding of displacement/excursion- making it difficult to get high spl at low frequencies.

Hmm, what would suggest that we are unfamiliar with the aforementioned alignments?

[pkm]

Originally posted by thadman
As is the situation with the 18sound midrange drivers, I haven't been able to track down much information regarding prosound subwoofers.

Who makes the lowest distortion prosound subwoofers? As far as alignment, lets say Infinite Baffle or LT.

The only high performance drivers that I'm aware of that may possibly be given this title are the BMS 18N850, 18Sound 21LW1400, or PD2150/PD2450. What other options are available?

I think your barking up the wrong tree.
Your looking for high Xmax in a high Sensitivity pro sound speaker.Sure their Xmech is high though.

Actual distortion measurements will need to be carried out on all drivers under same conditions.

[pkm]

Some measurements of HT woofers

http://www.mfk-projects.com/

[lne937s]

Originally posted by thadman


Hmm, what would suggest that we are unfamiliar with the aforementioned alignments?

I might have misunderstood, but the comment from Eva about "alignments demanding the highest cone displacement for a given SPL" and that the Linkwitz Transform was developed for dipoles to counteract dipole cancellation.

Going by the general rule of: small size/high efficiency/depth- you can have 2, but not all three. The infinite baffle functions like an infinitely large sealed subwoofer, so it should produce low frequencies efficiently. As such, it would tend to be efficient compared to other sealed alignments (which tend to be low distortion), and therefore not be creating high levels of distortion due to trying to counteract forces of nature...

You just need to make sure you have a subwoofer that fits the application (stiff enough suspension, etc.)

You may want to look at this popular choice for IB... 4 in a manifold with a 500w amp should get you (especially with room gain) quit a bit of low end grunt without any EQ.
http://www.partsexpress.com/pe/showd...number=295-455