The "designing the perfect subwoofer driver" thread... (1 Viewer)

[Anthony_Gomez]

Free!....Jack Gilvey has gratiously paid for everyone's drivers!!!! ...so that we can each have a pair!!!
Thank you Jack

 

[Craig Woodhall]

Anthony, that is the best news Ive had all year.. I just signed up with 3 new aliases to intitle me to to 3 pairs. Hmm, now what am i gonna do for amps

 

[Anthony_Gomez]

Amps? Well let me tell you.... Chris A is going to hook us up there with Free amps!!!!

And Brian Bunge is going to make free enclosures!!!!

And I will give out free speaker wire (1" stereo per person)

(just don't tell jack, chris, brian or myself this!)

 

[Craig Woodhall]

everytime I check back here, its getting sweeter and sweeter.. I love this forum and my pals!

 

[Anthony_Gomez]

Send love my way, cause when brian, chris and jack show up on my door step in the morning, there will be a shortage of love

 

[Kyle Richardson]

This is as specific as I can get right now. I cannot get more specific because final pricing has not been set or made known to me just yet.

From the preorder page:

Expect regular price to be between $350-$400 and preorder price between $300-$350

 

[Brian Bunge]

Chris,
I got a very interesting letter in the mail a few weeks ago concerning Adrian. Sounds like he greatly misrepresented himself.
Tony,
If you didn't have $76 of my money at the moment I'd have to come out there and kick 'yer ass! And don't forget, with Jack being in Jersey he's gotta have some Mafia connections!
Brian

 

[Jack Gilvey]

And don't forget, with Jack being in Jersey he's gotta have some Mafia connections!

Actually, I believe Tony Soprano's house is in North Caldwell, which is right next to me here in Verona...

 

[Brian Bunge]

Jack,

I have a friend in Philly that I love to pester on another forum. She is constantly threating to send her hitman down to "get me"!

Brian

 

[Anthony_Gomez]

Good thing I just purchased some laser goggles. When I set up the perimiter with the YAG:Harmonics laser, I will be safe from the invisible laser...but everyone else will be blind muahahahaha!!! ..oh damn it!!!..I gave away too much....it is the CO2 laser...really it is!!!

 

[ChrisA]

Jack,

I used to go to Audio Connection, John Rutan, in Verona a while back (6 yrs ago).

As far as Adrian is concerned, I'm bitting my tongue in a big way regarding my anger.

 

[Jack Gilvey]

Audio Connection is just up the block on Bloomfield. Great place. They've added another building and a whole suite of sound rooms. John's a cool dude.

 

[Seth_L]

Just spoke with Dan. Final prototype should hopefully be finished by the end of the week with the preorder beginning next week. They are just ironing out the right combination of spider and suspension that will work best. Thanks for your patience.

When will we know what volume the driver displaces? (basket, magnet, etc) Once I know this I can buy the wood for my box and start cutting. I've got all my PRs, but I don't know the true volume I need to have in the box. Once I know this I'll be ready to cut.

Seth

 

[Anthony_Gomez]

I'd expect it to be very close to the Brahma 15. you can always over size a little and use wood blocks to make up the volume difference.

 

[ChrisA]

I am also highly concerned about the accuracy of DUMAX and really think it is neccessary to use KLIPPEL for evaluating subwoofers. I don't see any other way to properly evalute subwoofers unless Klippel is utilized. Klippel is the only way to go as far as I am concerned, and this needs to be addressed.

Chris

 

[Anthony_Gomez]

Chris, if you just need basic T/S parameters, you can do it at home with a box, resistor and DMM (with test tones).
but if you want all the details, then I agree with you

 

[Jack Gilvey]

I am also highly concerned about the accuracy of DUMAX and really think it is neccessary to use KLIPPEL for evaluating subwoofers. I don't see any other way to properly evalute subwoofers unless Klippel is utilized. Klippel is the only way to go as far as I am concerned, and this needs to be addressed.

Agreed, as does Dan Wiggins it seems. He refers to Klippel a few times in the XBL2 white papers, and this motor is designed to address large-, as well as small-, signal performance/distortion. Klippel is a main supporter, I think, of BL linearity, and that is something Dumax can illustrate.

 

[John E Janowitz]

I am also concerned about the accuracy of DUMAX numbers. Two identical versions of our HE15 were sent for testing. This woofer has a 1.4" gap plate, and 3.4" long coil. A full inch of overhang on each end. The first results came back showing only 17mm Xmag. This can't be right since we should have around 25mm + 15%. This is the typical value for overhung woofers with a thick top plate. We sent just a motor without the suspension attached and they measured. They came up with 36mm Xmag on the motor itself. They then determined they had problems with their measurement methods. The surround resonance of the woofer actually screwed up their measurements. It has been shown that some woofers benefited from this problem and were shown to have more Xmag than they should have. Ours on the otherhand was severely hurt by this. They then remeasured the woofer and this time verified 30.65mm Xmag. Still not quite where it should have been since the motor itself was shown to have 36mm Xmag, and Xmag shouldn't change whether you add on suspension or not.

Another thing concerning is their simple T/S parameter extraction. Both woofers were measured with LMS and MLSSA to show Qts values of right around .4, before they were sent to DLC. The first one was measured and shown to have that .4 Qts value. The second one when measured was shown to have a Qts of .56. I still have not received explanation as to why this has happened.

I do believe Klippel is a much better system, and hopefully in the future we will see it taking more of a spotlight instead of DUMAX.

John

 

[eric]

if im remembering correctly, the klippel method doesnt give a numerical answer as to xmax, correct? the 'xmax race' is a big thing right now, unfortunately...and until someone puts a stop to it, i really dont see klippels methods becoming mainstream. the masses want a quantifiable way of comparing products, and accurate or not, dumax provides this data.

eric

 

[Jack Gilvey]

the masses want a quantifiable way of comparing products, and accurate or not, dumax provides this data.

What do the "non-masses" do to comare woofers, then? What data do they use, if any? If anything, Klippel is more concerned with large signals/high excursions, and gives a better idea of woofer performance at high excursion.