Sorry for the newbie question, but how do you calculate those directivity matching at 2000hz for a 6.5'' or a 8''?? What about if the crossover point was 1800hz?
Thats a great project :
www.avsforum.com/forwwwum/155-diy-s...3-way-triple-12-inch-beyma-tpl-150-amt-6.html
Faital speakers seem to be well performing. And that Faital sub is giving water in my mouth....
FaitalPRO | LF Loudspeakers | 12RS1066
www.avsforum.com/forwwwum/155-diy-s...3-way-triple-12-inch-beyma-tpl-150-amt-6.html
Faital speakers seem to be well performing. And that Faital sub is giving water in my mouth....
FaitalPRO | LF Loudspeakers | 12RS1066
I'm not exactly sure, and it would be great if @LewinskiH01 would show working, but one rough method as sited from here:http://www.diyaudio.com/forums/multi-way/231551-beyma-12p80nd-tpl-150-a-10.html
"...djk has provided a clever rule of thumb for calculating the dispersion for a given driver size at a given frequency - the "1,000,000" rule:
1,000,000 / Cone size in inches / dispersion in degrees = frequency in Hz
..."cone size in inches" refer to the actual cone size of the driver, which is usually a little less than the "formal" size...
For instance, a 10" PHL 3451 mid driver has an actual cone size diameter = 8.27". Thus, the frequency for which the dispersion for the 10" PHL 3451 would be 80° is:
1,000,000 / 8.27" / 80° = 1511.48 Hz"
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You can find good quality polar measurements on a few of the more popular midbass speakers like: the 12" JBL 2206 which shows a smooth response at 1,280Hz with 90-100degree polar directivity; and like the 10" JBL 2123 which is used by Disneyland with a ~1,200Hx crossover to a 120-degree horizontal polar pattern horn, and by some diy-audio with ~1700Hx crossover to a 90-degree horizontal horn. Sometimes the vendor SPL/freq data includes 15-30-45 degree curves with enough data for a leap of faith.
Polar/beaming estimates from the cone diameter can be a crude first estimate, but the cone shape, the width of the edge suspension, the dust cap, etc.... can create variations, and also poorly estimate break-up and resonances. You want a SMOOTH polar pattern on both sides of the crossover frequency.
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That is exactly how I go about it. Learnt it from djk. It's good for a rough estimate.
I made some progress with my project
I'm going to try this with goodmans audiom 61(97-98db/w) in the blh to 100-250hz then an axiom 301 open back to 2k to the tpl150h. I'm keeping a close eye on the horn loaded cone driver thread as I like to try a 6-8" mid horn loaded to keep the tpl150h 's efficiency. It'd be great if someone could recommend a horn design and driver that would do 220-2k, I'm a bit lost with all the different designs being used.
Enzo
I'm going to try this with goodmans audiom 61(97-98db/w) in the blh to 100-250hz then an axiom 301 open back to 2k to the tpl150h. I'm keeping a close eye on the horn loaded cone driver thread as I like to try a 6-8" mid horn loaded to keep the tpl150h 's efficiency. It'd be great if someone could recommend a horn design and driver that would do 220-2k, I'm a bit lost with all the different designs being used.
Enzo
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An externally hosted image should be here but it was not working when we last tested it.
15"
6.5"
tpl
450hz/2000hz
measured in room
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That's not the first review mentioning listening fatigue at higher volumes with AMTs...
Frequency response of the 12p80nd vs 12p80fe.
[Projet HR] Enceinte 2 voies RCF nd350 / Beyma 12p80nd - Page 2 - 30074104 - sur le forum Enceintes - 1464 - du site Homecinema-fr.com
[Projet HR] Enceinte 2 voies RCF nd350 / Beyma 12p80nd - Page 2 - 30074104 - sur le forum Enceintes - 1464 - du site Homecinema-fr.com
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come on, why not simply do a 2 way system, one TPL150, one 15" woofer, till the end of the world.
Because some of us have tried it and found better ways to get the result we want.
But I'm with frangus: read the thread. Then you might have something worthwhile to add.