“Loading” of tweeters in large drivers Coaxes

[Brett]

Wouldn't it have been simpler just to give a model number?

 

[Cal Weldon]

APT 50 perhaps?

http://www.eminence-speaker.com/proaudio_drivers_detail.asp?web_detail_link=APT50

 

[dantheman]

Wouldn't it have been simpler just to give a model number?

Had I known it.

Dan

 

[CLS]

Here's some measurements I took of a 15" UBaffle coax 1 meter away, ....

The tweeter is the cheapest Eminence compression model
...

For a WG comparison, here's the same tweeter on a 12" Parts Express waveguide under similar conditions otherwise.
....

? So you mounted the APT tweeter onto a 15" driver to made it a coaxial ?

I haven't found any Eminence coaxial in that size.

The limited ability of downward frequency of the APT tweeter makes it unsuitable for a large coaxial. It's said to be good above 3kHz. And it showed obvious drop off below around 2kHz in the above measurements. No wonder the dip seen in off-axis of coaxial.

 

[noah katz]

It does load the woofer; Tom Danley said recently at AVS that it increases low freq sensitivity by 6 dB IIRC, which is padded down to keep response flat, but increases headroom by that amount.

Yes I've also noticed that SH100, a very interesting speaker.

Its directivity is 110 degree, as I've mentioned it'd better be wide. And I believe the WG is more of a directivity control, less of loading. As the sensitivity is 'only' 95dB/2.83v...

 

[dantheman]

? So you mounted the APT tweeter onto a 15" driver to made it a coaxial ?

I haven't found any Eminence coaxial in that size.

The limited ability of downward frequency of the APT tweeter makes it unsuitable for a large coaxial. It's said to be good above 3kHz. And it showed obvious drop off below around 2kHz in the above measurements. No wonder the dip seen in off-axis of coaxial.

I never said APT--Cal Weldon did. He didn't click the link either. The tweeter is the Eminence ASD1001S as I linked previously when replying to the first poster that asked the question. No I didn't attach a 12 and a 10 inch waveguide onto a 15inch coaxial speaker. The measuring conditions were the same--3ft away and gated appropriately. I never said an Eminence coax even though it is. Eminence makes 15" coaxial speakers for other companies OEM style. They used to make them for themselves as well but I'm not sure they still do or not. The dip below the crossover frequency and is caused by the beaming of the woofer and has nothing to do with the tweeter. 15" woofers don't do well generally over 1 kHz.

Hope that clarifies,

Dan

Please don't assume when reading posts. It can only make things more confusing. And please don't get upset if I'm blunt. It's not personal. I just hate writing more than I have to most of the time.