asterisk users - Jul 2010 - How to calculate number of speakers needed for PAGING and INTERCOM coverage area?

Hi Guys,

I am looking to buy a 25 Watt output CyberData VoIP amplifier and to use 2
Bogen sp308a speakers with it for a 40, 000 squar feet area and 21 feet
height. Is that enough? Is there calculator online I can use to determine
the number of speakers needed? I guess these speakers go in chain so I am
not sure if the full capacity of the speaker (30 watt) will be used.

I appreciate your advice.

Thanks,
Bruce
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bruce bruce ha scritto:
> Hi Guys,
> 
> I am looking to buy a 25 Watt output CyberData VoIP amplifier and to use
> 2 Bogen sp308a speakers with it for a 40, 000 squar feet area and 21
> feet height. Is that enough? Is there calculator online I can use to
> determine the number of speakers needed? I guess these speakers go in
> chain so I am not sure if the full capacity of the speaker (30 watt)
> will be used.
Hummmm interesting... i never checked this kind of product.

CyberData has calculator only for the 8W model, but... every speaker
they sell is 8w and the calculator say 69 speakers. You can attach 2
speakers to one amplifier in parallel (they say this also), this is
the maximum as the amplifier cannot reach 32W (4 speakers), but you
can try to use 4 speakers (2 in parallel + 2 in parallel) with a
little less than maximum 8w on each speaker.

I think a reasonable number of speakers may be less than half, but you
must check wath is in the area, also remember if this is a warehouse
to place the speakers where a person can be, not goods. :-)

For a so big installation think to use a voip interface and
professional product with low voltage line speakers, i think is less
expensive.

Bye.
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Thanks fro the input. The area is a 40000 square feet. So, you are saying
that if I use four speakers then they would not be as loud as needed?

Thanks again

2010/7/9 Massimo Nuvoli <massimo at archivio.it>
> bruce bruce ha scritto:
> > Hi Guys,
> >
> > I am looking to buy a 25 Watt output CyberData VoIP amplifier and to
use
> > 2 Bogen sp308a speakers with it for a 40, 000 squar feet area and 21
> > feet height. Is that enough? Is there calculator online I can use to
> > determine the number of speakers needed? I guess these speakers go in
> > chain so I am not sure if the full capacity of the speaker (30 watt)
> > will be used.
>
> Hummmm interesting... i never checked this kind of product.
>
> CyberData has calculator only for the 8W model, but... every speaker
> they sell is 8w and the calculator say 69 speakers. You can attach 2
> speakers to one amplifier in parallel (they say this also), this is
> the maximum as the amplifier cannot reach 32W (4 speakers), but you
> can try to use 4 speakers (2 in parallel + 2 in parallel) with a
> little less than maximum 8w on each speaker.
>
> I think a reasonable number of speakers may be less than half, but you
> must check wath is in the area, also remember if this is a warehouse
> to place the speakers where a person can be, not goods. :-)
>
> For a so big installation think to use a voip interface and
> professional product with low voltage line speakers, i think is less
> expensive.
>
> Bye.
>
> --
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In my experience using height for radius works, for example if you
have a 20 ft high ceiling then the coverage for one speaker would be
40 ft diameter circle (around 1200 sq ft). Of course overlapping 5 ft
has never killed anyone, but this really depends on the power of the
speaker, I usually deal with 70v speakers tapped at 16 or 8 watts
depending on how many speakers I put on one amplifier and the output
wattage of that amplifier.



On Fri, Jul 9, 2010 at 2:29 AM, bruce bruce <bruceb444 at gmail.com>
wrote:
> Hi Guys,
> I am looking to buy a 25 Watt output CyberData VoIP amplifier and to use 2
> Bogen sp308a speakers with it for a 40, 000 squar feet area and 21 feet
> height. Is that enough? Is there calculator online I can use to determine
> the number of speakers needed? I guess these speakers go in chain so I am
> not sure if the full capacity of the speaker (30 watt) will be used.
> I appreciate your advice.
> Thanks,
> Bruce
> --
> _____________________________________________________________________
> -- Bandwidth and Colocation Provided by http://www.api-digital.com --
> New to Asterisk? Join us for a live introductory webinar every Thurs:
> ? ? ? ? ? ? ? http://www.asterisk.org/hello
>
> asterisk-users mailing list
> To UNSUBSCRIBE or update options visit:
> ? http://lists.digium.com/mailman/listinfo/asterisk-users
>