Rerurn to Romy the Cat's Site


In the Forum: Audio Discussions
In the Thread: Exceptional loudspeakers drivers
Post Subject: In the real world of the 18-inchers...Posted by Romy the Cat on: 4/7/2007

Hm, the 18mm out of 50mm in “fully in-gap mode” for Aura? It sounds too bad.  The last time I touched this subject it was 6 years ago and I remember I had better impression in term of the numbers.

I just looked at the Aura page:

http://www.aurasound.com/public/discontinued/images/spec/nrt1808_b.jpg

It has Xmax = 18mm(.71”) but, Jessie, you forget that Xmax is one-way excursion.

The next page sad:

http://www.aurasound.com/public/discontinued/images/spec/nrt1808_a.jpg

The Linear Excursion (pick-to-pick) 38mm (1.5”) out of 50mm (2”). That sounds more what the “consumer” numbers that I remember.

Also a few further comments. Aura is 5dB more sensitive then McCauley.  The other notable difference is the material of suspension. McCauley suspends fiber cone with rubber, while Aura uses fiber composites and suspends it with soaked fabrics. The epoxy reinforcement that you mention used only in Aura to glue the cloth to the driver. It  is not much epoxy but it is still not good – epoxy must not be use anywhere on the drivers (though we do not know how McCauley glue rubber to cone).  O do not know the neodymium vs. “soft iron magnets”. Generally higher BL factor considered better but it is not always the case. It should be heard in order to recognized how it warks all together.

It is possible that McCauley is fine 18-incher. The problem is that it is VERY difficult to sonically evaliate the sound of those drivers in the equal conditions. If one has in his possession for instance that McCauley 6174, the Aura 1808 and the Seismic 8196 then can you imagine a person to modify those huge boxed in order to make the operating conditions equal? So, I feel in the real workd a person makes a purely intellectual decision and then juts go with the selected driver, trying to get the best out of the given design/driver.

The caT

Rerurn to Romy the Cat's Site