Audax AP210Z0 8" Aerogel Midwoofers

[BAM]

.oOkay... I've had a pair of these hanging out in my room for just a couple months shy of a year, and I've been debating what to do with these things. I bought them from Parts Express because I wanted to try building something with the aerogel cones. They seem to be poor performers in small enclosures. I've been told that this is because they have relatively weak motors.

Is there really no other choice other than to build monstrous towers for these? Or, could I integrate a small quarter-wave stub into the back of a stand-mount enclosure to fight the rising acoustic impedance and gain some extra output at a lower frequency?

Also, another question: Should I expect to be able to do a two-way design with these woofers, or is a three-way design necessary? I'd like to use a Seas aluminum dome tweeter, either the 22TAF/G (H1283) or the 25TAF/G (H398). I think the H1283 is the cooler option because it has a design similar to the Vifa/Scan-Speak tweeters that are based on their ring radiators, in which a larger outer suspension and higher-excursion motor are used to allow a lower Fs but retain an extended top end. Could I expect to mate the AP210Z0 and H1283?

Addendum:
Whoops...the H1283 isn't shielded. Could someone recommend a shielded tweeter that I could use for all channels of a multichannel sound system? The H569 is the one I'd like to take a look at, because I already have had good results with the H537 (which is the H569 with a back chamber).

[sreten]

http://www.hautparleur.fr/_audax/ap210z0.pdf

Hi,

A BL of 8.1 is not too shabby, the Qts of 0.32 (which indicates a
strong motor) also indicates sealed box performance will be poor,
the driver is designed for reflex loading in 25L to 45L boxes.

You haven't searched on AP210Z0 ..............

/sreten.

[D1GGY]

You may find this Useful

m

[BAM]

It looks like I might be able to accomplish something in the stand-mount form factor if I accept that whatever I design is going to be big. Right now, a 1.46 cubic foot vented or passive radiator enclosure tuned to 45 Hz offers the best in bass extension. These will likely be used with a subwoofer, so if I want to go even smaller, I could go for a sealed enclosure with an F3 of 63 Hz, but it seems to me like I should be able to expect deeper response from a speaker with an 8" woofer, so I think vented is it.

[sreten]

Hi,

You should go sealed if you want use a subwoofer, integration will be far easier.
Not only that, the smaller boxes resonant performance will be better.

You can't simply judge the level of bass extension available from a driver
by its apparent size, things are complicated by the efficiency of the driver.

/sreten.

[AndrewT]

Hi,
Audax's ZOs were designed for light weight to give good sound. The side effect from the light weight is higher efficiency and higher Fs.
The first saves power but the second limits bass extension.

The slightly heavier COs go much lower if you had wanted bass extension.

A sub seems like the complicated solution and due to the cone size in the 210, you may decide to use a mid driver as well. Complicated 4way is looming.