Distance screen to last row is 24.5 meter. I use the 2/3 depth rule. So target SPL 85dB at 16 meters distance. 15 Inch coax 99- 97dB/W/m? 1.200 Watts amplifier? I don't mind a wee bit less then the 85dB target. Used to running a Dolby processor at 5 instead of 7.
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Distance screen to last row is 24.5 meter. I use the 2/3 depth rule. So target SPL 85dB at 16 meters distance. 15 Inch coax 99- 97dB/W/m? 1.200 Watts amplifier? I don't mind a wee bit less then the 85dB target. Used to running a Dolby processor at 5 instead of 7.
It depends a lot on the specific speaker, but yeah, 1200WPC would give you a couple of dB of head room if the efficiency is accurate. Width of seating area?
Subs? Speaker choices open up when you add a sub or two.
Seating area like in a drive inn theater, 90 degrees. Probably will use Celestion FTX1530 Coax. Sub probably 18 inch horn, to get the extra 10dB headroom for sub channel.
Now to my question about very big baffles, does anybody know a online calculator or has experience with very, very wide baffles? How about extending the hornmouth with a 10 feet wide baffle?
Now to my question about very big baffles, does anybody know a online calculator or has experience with very, very wide baffles? How about extending the hornmouth with a 10 feet wide baffle?
The coax speakers will need a smaller inductor in line with the bass section. I misused the Edge to optimize 2π placement for the LCR speakers. No baffle step needed.
How about a 2 x 2 foot hornopening with 10 feeft left and right and 8 feet above baffle? Placement close to the ground.
How about a 2 x 2 foot hornopening with 10 feeft left and right and 8 feet above baffle? Placement close to the ground.
Depending on how much LF you want, you might find that several 18"s are required.
Putting it in Danley terms for a moment, the SM80 is recommended to be partnered with 1-4 TH118s, dependent on program material.
The SM80 IIRC uses a 350w RMS B&C 12" coaxial. ie, a high-power 15" coaxial will probably have more output, and therefore need more subwoofers to keep up.
Chris
Putting it in Danley terms for a moment, the SM80 is recommended to be partnered with 1-4 TH118s, dependent on program material.
The SM80 IIRC uses a 350w RMS B&C 12" coaxial. ie, a high-power 15" coaxial will probably have more output, and therefore need more subwoofers to keep up.
Chris
Thanks for the reference. I did several openair screenings with the help of local dj's and his equipment. EV 12 inch 2-ways + smallish EV sub. I agree about more dynamic headroom beeing welcome (isn't it always). Hope to have a bit of a subboost by using the shipping container as a really big baffle.