DATS vs Acoustic Elegance

[Kapton Planet]

Camplo,

I wouldn't blame this on break-in or DATS. It looks like your magnet is weak. The Qes is way too high and BL is too low, but everything else is as expected. What did John J. say about it?

[camplo]

He pointed to some data that was off, mmd, and effective diameter to be specific...he scape goated the Q specs on break in and told me in so many words that he could only get the advertised specs by using a super rigid metal frame for testing. He tried to say that the little resonant peaks were from "movement"

In hindsight be gave me a calculated lie....The BL of the 15m and 18H+ are all 25% lower than advertised...using MMD he gave me for the 16ohm 15m and the advertised mmd for the 8ohm 18h+ I still came out 75% power of advertised BL...

By the way, after that email....I never heard from them again, considering many emails showing my measurements following....I even offered to mail the woofers back to have them tested at my expense...and to pay for shipping them back to me as long as it all checked out.....That was over a week ago....hes stone walled me.

[johnnyrichards]

He pointed to some data that was off, mmd, and effective diameter to be specific...he scape goated the Q specs on break in and told me in so many words that he could only get the advertised specs by using a super rigid metal frame for testing. He tried to say that the little resonant peaks were from "movement"

In hindsight be gave me a calculated lie....The BL of the 15m and 18H+ are all 25% lower than advertised...using MMD he gave me for the 16ohm 15m and the advertised mmd for the 8ohm 18h+ I still came out 75% power of advertised BL...

By the way, after that email....I never heard from them again, considering many emails showing my measurements following....I even offered to mail the woofers back to have them tested at my expense...and to pay for shipping them back to me as long as it all checked out.....That was over a week ago....hes stone walled me.

Ummm who?

[camplo]

John of Acoustic elegance

[camplo]

The Qts of the 18h+ are fine, though motor strength is 75% just like with the 15m. I can adjust the qts with a resistor from what I understand. So I could potentially move forward with my design thats based around these drivers.....
My question is how will this motor strength issue impact sound quality?

[dynamo]

The Qts of the 18h+ are fine, though motor strength is 75% just like with the 15m. I can adjust the qts with a resistor from what I understand. So I could potentially move forward with my design thats based around these drivers.....
My question is how will this motor strength issue impact sound quality?

They’re probably all garbage and not worth messing with. I’ll do you a huge favor and let you send them to my house and I will properly dispose of them for you..

[dynamo]

I think you are worrying about something not worth worrying about.

100% accurate

[camplo]

I've more so, come to the conclusion that these drivers aren't exactly, bummy....its just that Acoustic Elegance has bloated the hell out of the advertised specs....not a new concept I supose....The part where they really screwed me is that telling me the thiele specs of the 16ohm voice coils would line with the 8ohm so that I wouldn't have to change my design....this is before choosin the 16ohm coils....so now my qts is off and the only way to adjust qts ( with a resistor) will result in a negative impact on efficiency....thats pretty crappy of them to set me up like this....the design is intended to reach critical damping ie qtc 0.5 and I cannot do this with the current box/woofer combo

[scholl]

can you put them in the intended box and measure the FR? If the Qs are so far off you'll see it quick.

[DeZZar]

Driver needs break in before you can conclude anything about the Q's.

[camplo]

The best question I've had so far....might be an easy one....You need to know BL to know qes and you must know Qes to know Bl...So how is the DATs figuring out Qes without BL?

[DeZZar]

Qes is not calculated from BL.

[camplo]

Qes = 2 Pi x Fs x Mms / (Bl2/Re)

Bl2= (2 Pi x Fs x Mms / Qes) x Re

[DeZZar]

http://www.wavecor.com/Measuring_driver_Q-values.pdf
https://sound-au.com/tsp.htm
https://www.bksv.com/media/doc/bo0384.pdf (3.3 Qes)

[camplo]

I was looking at that earlier...I believe the dats uses this approach to figure qes...

How do you think it figures CMS?
I think in your second link is the answer.