Subwoofer driver buy-in poll

[Chris Brunhaver]

Attached are the T/S parameters and Klippel data from the review. I'm not an expert in copyright law so if the mods need to take it down, I respect that.

The editorialize a bit, obviously with an 18.25 mm "underhang" and a long coil the driver has very linear BL and due to using a 6" diameter 2-layer coil and copper sleeve on the has very high power handling and good low Le, good Xmax etc.

I know that drivers like this and the LMS TC sounds stuff capture the imagination of DIYers but I think that people are missing the point a bit. With the research that has been done by Harman and others showing how multiple LF sources having a very positive impact in smoothing rooms modal responses, the question isn't who can build the best $1k woofer, unless you have a lot of money to build 4 of them. Instead, four $250 woofers would be a better bet for that $1k budget. As engineering is really the art of doing the most with the least (and furthermore fits within the demands of the application from all other factors therein) these brute force approaches are not that interesting to me personally.

[Ricci]

The data looks pretty good to me.

[avaserfi]

Chris Brunhaver wrote:

I know that drivers like this and the LMS TC sounds stuff capture the imagination of DIYers but I think that people are missing the point a bit. With the research that has been done by Harman and others showing how multiple LF sources having a very positive impact in smoothing rooms modal responses, the question isn't who can build the best $1k woofer, unless you have a lot of money to build 4 of them. Instead, four $250 woofers would be a better bet for that $1k budget. As engineering is really the art of doing the most with the least (and furthermore fits within the demands of the application from all other factors therein) these brute force approaches are not that interesting to me personally.

I completely agree with you on this one. Also, the Infinity Kappa Perfect/VQ series is a perfect high quality budget option for such a situation. Eventually I will have four of them in use for movies and two in stereo use for 2-channel listening.

The thing is raw power just seems so much cooler than a bunch of "little" subs.

[vinculum]

We're just evaluating the driver here, not a bass system. If you have $1000 to spend and your goal is value based, then Acoupower isn't the best bang for the buck. Four lower cost drivers would then make the most sense. I have 2 of these Acoupower 18" drivers which will be non co-located. I'm not really on a budget so, I'd have no problem getting 2 more if needed.

Chris, thanks for sharing that data. I was also expecting an article to go along with it. If there is one, could you include that?

Thanks!
Dr V

[ISLAND1000]

There are many ways to energize a listening area with low frequency power. I'm among those who like to see it done with just a couple drivers in smaller boxes. To do that requires special build qualities and design techniques using special materials and a person with a unique personal drive to keep advancing the technology. Acoupower is one of those special drivers.
Sub drivers more than mid range or tweeters peak my interest, kinda like other things that fit formulas IE: 12 oz. Bud Light, Dbl quarter pounder w/cheese, 36-24-36, Corvette Z06, etc.

[noah katz]

"With the research that has been done by Harman and others showing how multiple LF sources having a very positive impact in smoothing rooms modal responses, the question isn't who can build the best $1k woofer, unless you have a lot of money to build 4 of them."

I agree, but note that two subs gave results nearly as good as four and is much more practical for most people.

[SteveCallas]

Chris wrote:

I know that drivers like this and the LMS TC sounds stuff capture the imagination of DIYers but I think that people are missing the point a bit. With the research that has been done by Harman and others showing how multiple LF sources having a very positive impact in smoothing rooms modal responses, the question isn't who can build the best $1k woofer, unless you have a lot of money to build 4 of them. Instead, four $250 woofers would be a better bet for that $1k budget. As engineering is really the art of doing the most with the least (and furthermore fits within the demands of the application from all other factors therein) these brute force approaches are not that interesting to me personally.

Absolutely. I don't get the mega bucks driver that requires a mega bucks amplifier that requires a dedicated 20 amp line approach unless one is absolutely strapped for space.

[Larry McConville]

Valid points; however, we must realize this is a hobby and folks have different tastes. I believe it keeps the hobby enjoyable and engaging.

SteveCallas wrote:

Absolutely. I don't get the mega bucks driver that requires a mega bucks amplifier that requires a dedicated 20 amp line approach unless one is absolutely strapped for space.

[vinculum]

Compromise has many avenues. Some may be strapped for space, others may be strapped for cash. DIYers strive to do the best with what is available to them.

[anidabi]

Ilkka wrote:

And if the Maelstrom 18 (XJ-18) will be ready before my tests begin, it will also going to be tested.

I sure hope to see this thing at your subwoofer shootout. The final engineering sample parameters have been published and the production should start during april. So I guess it will not be in the spring shootout?

Here you can find the parameters.

[marstedt]

I would like to see the Mach5Audio IXL-18.4 as well as the MJ-18 tested since these are both easily accessible in Canada.

[Blaser]

A bit late to this thread but I will have my word:

I wonder why we are making Ilkka's life difficult with so many questions/investigations. What is so hard not to understand?
Illka is one of the biggest (if not the biggest) subwoofer tester in the world, and he is young (BTW). Nevertheless he has tested so many subs and we all benefit from the results for free.

Now either you are willing to help, or you aren't. If you are, consider this money an encouragement to Ilkka for the unpaid time and efforts that he is doing exclusively for the shacksters, leave aside all the investment that has done in these tests as far as drivers/enclosures/shipping/transportation....

I don't give a care to my 40 or 50 bucks that I donate after the tests for a specific driver or whatever. Just consider it as an encouragement to Ilkka's tests. But the kinda "what will our money become when it is transformed into a sub" is not very ethical IMO.

[vinculum]

Ilkka,

How are we doing on acquiring an Acoupower driver for testing?

I just noticed there is a 15% off sale for Acoupower drivers for the month of April. A great time to buy if we have enough interest! I'll chip in a little more if it will make a difference...

Dr V

[Ilkka]

vinculum wrote:

Ilkka,

How are we doing on acquiring an Acoupower driver for testing?

I just noticed there is a 15% off sale for Acoupower drivers for the month of April. A great time to buy if we have enough interest! I'll chip in a little more if it will make a difference...

Dr V

I though we were progressing quite nicely but now Carlos haven't replied to my e-mails for a quite a long time. I don't know what's happening.

[noah katz]

I wish he would stop disappearing like that, it reduces one's confidence in support for the product being available if needed.

[funky_waves]

Last time I talked with carlos, last week I believe, he is very busy. I would call him. It sounded like he would like to get one to Illka.

[vinculum]

Ilkka wrote:

I though we were progressing quite nicely but now Carlos haven't replied to my e-mails for a quite a long time. I don't know what's happening.

I talked to him via email last night. I nudged him a little, hopefully he will get back to you. He is now an authorized Crown dealer!

I'm now a Crown man myself, having picked up a pair of CE4000's.

Dr V

[funky_waves]

I think we should all call and nudge him, I realy want to see tests on this sub now, that I have one, listening to it right now. I was sceptical, I knew it would be great but I wasnt sure if it would measure up, haveing gotten used to the LMS5400

[noah katz]

"I was sceptical, I knew it would be great but I wasnt sure if it would measure up, haveing gotten used to the LMS5400"

And the verdict is....

[funky_waves]

To early for a verdict, but it definitly rivals the LMS. It seems to have better upper bass in initial impression. Very articulate and accurate bass. I will have to swap them back and forth a few times to see for sure what I prefere.

[noah katz]

"To early for a verdict, but it definitly rivals the LMS. "

Sounds promising, thanks.