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Title: Mono sum + HPF
Post by: luis Markson on April 19, 2011, 03:24:59 AM
For a retail environments,  I am assuming that in ceiling speakers are summed to mono?

I'm looking at a particular powered system that requires a HPF @ 80Hz. Without delving into expensive DSP what cost effective units existed for mono summing that include a HPF?
Title: Re: Mono sum + HPF
Post by: Chris Carpenter on April 19, 2011, 03:50:25 AM
For a retail environments,  I am assuming that in ceiling speakers are summed to mono?

I'm looking at a particular powered system that requires a HPF @ 80Hz. Without delving into expensive DSP what cost effective units existed for mono summing that include a HPF?
For a retail environment, your typically looking at a 70v system. Quite a few places run these with integrated mixer/amplifier units that can take a line level signal. They usually do the summing on their own. HPF shouldn't really be necessary at retail volume levels.

What particular powered system, and for what application?
Title: Re: Mono sum + HPF
Post by: luis Markson on April 19, 2011, 04:33:24 AM
For a retail environment, your typically looking at a 70v system. Quite a few places run these with integrated mixer/amplifier units that can take a line level signal. They usually do the summing on their own. HPF shouldn't really be necessary at retail volume levels.

What particular powered system, and for what application?

I'm looking at this:

http://www.atprofessional.com.au/products/mk100.php

The space is a one room rectangle aprox' 10m x 5m

Subtle, ambient music
Title: Re: Mono sum + HPF
Post by: Brad Weber on April 19, 2011, 07:51:00 AM
For a retail environments,  I am assuming that in ceiling speakers are summed to mono?
Typically, although some retail applications will try to create stereo zones.

I'm looking at a particular powered system that requires a HPF @ 80Hz. Without delving into expensive DSP what cost effective units existed for mono summing that include a HPF?
So you're looking at the MK100A version and having to deal with an IEC power cord at each speaker location?  The manufacturer doesn't seem to offer information online beyond the basic product page data so I'm not sure where it is identified that the speaker needs an 80Hz high pass filter, but if it does then it seems that a 70V system might make sense as even cheaper transformers could probably handle that at ambient music levels without transformer low frequency saturation or response being a concern.
Title: Re: Mono sum + HPF
Post by: luis Markson on April 19, 2011, 08:17:41 AM
Typically, although some retail applications will try to create stereo zones.
So you're looking at the MK100A version and having to deal with an IEC power cord at each speaker location?  The manufacturer doesn't seem to offer information online beyond the basic product page data so I'm not sure where it is identified that the speaker needs an 80Hz high pass filter, but if it does then it seems that a 70V system might make sense as even cheaper transformers could probably handle that at ambient music levels without transformer low frequency saturation or response being a concern.

I'm trying to figure out if I can get away with 1 unit. The filter was recommended via a phone conversation.
Title: Re: Mono sum + HPF
Post by: Brad Weber on April 19, 2011, 10:52:11 AM
I'm trying to figure out if I can get away with 1 unit. The filter was recommended via a phone conversation.
How high will the speaker be mounted?  And do they provide any directivity information beyond the very nebulous 'high frequency dispersion' below 8kHz of 120 +/-10 degrees?  I'm a little curious as to how they get such wide dispersion from a simple single 4" full range driver.  Just for some comparison, an Atlas Sound FA114 in a FA97-4 enclosure is almost hemispherical at 1kHz and has a -6dB coverage of 135 degrees at 2kHz, about 100 degrees at 4kHz and around 50 degrees at 8kHz.  And the -6dB pattern for a Bose DS 40F is similar with about 120 degrees at 1kHz, 150 degrees at 2kHz, 100 degrees at 4kHz and 50 degrees at 8kHz.
 
And don't forget that with wide dispersion speakers the distance a listener is from the speaker can vary significantly within the -6dB coverage pattern.  Say the ceiling is 10' high and the listeners are standing, so a person directly under the speaker would be around 5' from it while someone 60 degrees off axis would be about 10' away from the speaker and thus more like 10-12dB down in level relative to the listener on axis.  Without any overlap from other speakers to compensate that could be a factor.
Title: Re: Mono sum + HPF
Post by: luis Markson on April 19, 2011, 07:25:17 PM
How high will the speaker be mounted?  And do they provide any directivity information beyond the very nebulous 'high frequency dispersion' below 8kHz of 120 +/-10 degrees?  I'm a little curious as to how they get such wide dispersion from a simple single 4" full range driver.  Just for some comparison, an Atlas Sound FA114 in a FA97-4 enclosure is almost hemispherical at 1kHz and has a -6dB coverage of 135 degrees at 2kHz, about 100 degrees at 4kHz and around 50 degrees at 8kHz.  And the -6dB pattern for a Bose DS 40F is similar with about 120 degrees at 1kHz, 150 degrees at 2kHz, 100 degrees at 4kHz and 50 degrees at 8kHz.
 
And don't forget that with wide dispersion speakers the distance a listener is from the speaker can vary significantly within the -6dB coverage pattern.  Say the ceiling is 10' high and the listeners are standing, so a person directly under the speaker would be around 5' from it while someone 60 degrees off axis would be about 10' away from the speaker and thus more like 10-12dB down in level relative to the listener on axis.  Without any overlap from other speakers to compensate that could be a factor.

I have more detailed specs on a printed brochure, I'll pull them out tonight...

I'm not sure of the placement yet, I'm looking for reasources to help determine that.

The ceiling height is about 8'
Title: Re: Mono sum + HPF
Post by: luis Markson on April 19, 2011, 08:54:20 PM
I have more detailed specs on a printed brochure, I'll pull them out tonight...

I'm not sure of the placement yet, I'm looking for reasources to help determine that.

The ceiling height is about 8'

Who are the main players in the constant voltage, in ceiling install market? Currently I am aware of Bose, QSC, Martin and Atlas...
Title: Re: Mono sum + HPF
Post by: Brad Weber on April 19, 2011, 10:07:19 PM
Who are the main players in the constant voltage, in ceiling install market? Currently I am aware of Base, QSC, Martin and Atlas...
Also Tannoy, TOA, JBL, Soundtube, Lowell and I'm sure I'm missing some others.
Title: Re: Mono sum + HPF
Post by: Chris Carpenter on April 19, 2011, 10:13:43 PM
Also Tannoy, TOA, JBL, Soundtube, Lowell and I'm sure I'm missing some others.
Ive been seeing more and more Bogen gear.
Title: Re: Mono sum + HPF
Post by: luis Markson on April 19, 2011, 11:45:41 PM
What is the simplest, entry level system design software package that exists?
Title: Re: Mono sum + HPF
Post by: Marcus Baeumler on April 20, 2011, 02:02:00 AM
What is the simplest, entry level system design software package that exists?
Thatīs probably EASE Focus. It is used by several manufacturers.
For example you can download it from QSCīs website with their speaker models included.


Marcus
Title: Re: Mono sum + HPF
Post by: luis Markson on April 20, 2011, 03:16:27 AM
Thatīs probably EASE Focus. It is used by several manufacturers.
For example you can download it from QSCīs website with their speaker models included.


Marcus

Aweasome...cheers...
Title: Re: Mono sum + HPF
Post by: luis Markson on April 20, 2011, 10:20:51 PM
Specs for MK100A

(http://img862.imageshack.us/img862/9159/photo139.jpg) (http://img862.imageshack.us/i/photo139.jpg/)

Uploaded with ImageShack.us (http://imageshack.us)

(http://img715.imageshack.us/img715/8767/photo138mr.jpg) (http://img715.imageshack.us/i/photo138mr.jpg/)

Uploaded with ImageShack.us (http://imageshack.us)

(http://img685.imageshack.us/img685/8056/photo137rr.jpg) (http://img685.imageshack.us/i/photo137rr.jpg/)

Uploaded with ImageShack.us (http://imageshack.us)


Title: Re: Mono sum + HPF
Post by: luis Markson on April 21, 2011, 01:45:16 AM
What is the simplest, entry level system design software package that exists?
Thatīs probably EASE Focus. It is used by several manufacturers.
For example you can download it from QSCīs website with their speaker models included.


Marcus

How would you go about making considerations for a pitched ceiling?

Title: Re: Mono sum + HPF
Post by: Brad Weber on April 21, 2011, 08:19:54 AM
Specs for MK100A

(http://img862.imageshack.us/img862/9159/photo139.jpg) (http://img862.imageshack.us/i/photo139.jpg/)

Uploaded with ImageShack.us (http://imageshack.us/)

(http://img715.imageshack.us/img715/8767/photo138mr.jpg) (http://img715.imageshack.us/i/photo138mr.jpg/)

Uploaded with ImageShack.us (http://imageshack.us/)

(http://img685.imageshack.us/img685/8056/photo137rr.jpg) (http://img685.imageshack.us/i/photo137rr.jpg/)

Uploaded with ImageShack.us (http://imageshack.us/)
Thanks for the added tech info!  What I see seems pretty typical of a 4" driver in a can with limited directionality below 2kHz and beaming above 6kHz.
 
I guess what to do depends on what you are trying to do.  Getting anywhere near even coverage of a 10m x 5m (33' x 16-1/2') space with people standing and an 8' ceiling would definitely require more than one speaker as that creates a rather small coverage area per speaker.  However, for this application even coverage may not really be a factor and the goal may instead be to draw patrons toward a specific point.
 
Many of the ceiling speaker manufacturers provide associated design tools. JBL and TOA offer downloadable design software specifically for their distributed ceiling speaker products while Tannoy and QSC offer versions of EASE Address for the same purpose.  SoundTube has a simple online calculator for recommended spacing and Atlas provides an Excel spreadsheet for their Strategy series speakers.  These are intended to be used for typical situations and some, if not all, may not allow for modeling features such as sloped ceilings.  If you want to do that then most of the manufacturers also provide EASE and/or CLF data that can be used in other modeling programs.
Title: Re: Mono sum + HPF
Post by: Chris Carpenter on April 21, 2011, 06:36:40 PM
Thatīs probably EASE Focus. It is used by several manufacturers.
For example you can download it from QSCīs website with their speaker models included.


Marcus


How would you go about making considerations for a pitched ceiling?
EASE Focus has settings for this, youll just need to play around with the program.
Title: Re: Mono sum + HPF
Post by: luis Markson on April 21, 2011, 09:36:50 PM
EASE Focus has settings for this, youll just need to play around with the program.

I've had a fiddle with EASE address. If I go with a 70v solution that seems to be the right software. Unfortunately I've got a house full of macs and EASE is windows only. I think I'm going to have to try running Parallels or something similar.

I'll have a look at EASE focus next time I'm on a PC.
Title: Re: Mono sum + HPF
Post by: Marcus Baeumler on April 22, 2011, 02:25:55 AM
I've had a fiddle with EASE address. If I go with a 70v solution that seems to be the right software. Unfortunately I've got a house full of macs and EASE is windows only. I think I'm going to have to try running Parallels or something similar.

I'll have a look at EASE address next time I'm on a PC.


btw: you found the right program... I mixed up EASE Focus and EASE Adress. Adress is for ceiling speakers and Focus for line arrays.
Marcus