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[Stephen Patterson]

My church is trying to improve our sound.  We are a non-instrumental church so our goal is speech/voice quality.  We've had a few pros do evaluations but cost is way out of our range (small church in a big building).

Bought a JBL CBT-70J, which sounds 10x better than current speakers (just holding it up on a ladder).  Asymmetrical appeals to us since current speakers are loud up front and inaudible in the back.  Room is 65' wide, 90' deep.  Just ordered another 70J yesterday (then found this forum today).

I'm looking for placement suggestions.  My current plan is to mount them directly on the rafter at the ceiling with a good downtilt (above where the old speakers are currently hanging).  I'd like to avoid hanging them down if possible.  (Speakers on the wall are old/dead but 13ft as a ref point).  Appreciate any suggestions.

[g'bye, Dick Rees]

My church is trying to improve our sound.  We are a non-instrumental church so our goal is speech/voice quality.  We've had a few pros do evaluations but cost is way out of our range (small church in a big building).

Bought a JBL CBT-70J, which sounds 10x better than current speakers (just holding it up on a ladder).  Asymmetrical appeals to us since current speakers are loud up front and inaudible in the back.  Room is 65' wide, 90' deep.  Just ordered another 70J yesterday (then found this forum today).

I'm looking for placement suggestions.  My current plan is to mount them directly on the rafter at the ceiling with a good downtilt (above where the old speakers are currently hanging).  I'd like to avoid hanging them down if possible.  (Speakers on the wall are old/dead but 13ft as a ref point).  Appreciate any suggestions.

Stephen...

The best placement for these (150 degree) speakers is a single line right in the middle of the space.  JBL should have some papers on this.  But most importantly:

You MUST have the properly certified flying hardware and you MUST have the installation done by a licensed, bonded contractor who is fully qualified to do such work.  THIS IS NOT A DIY SITUATION.  The validity of your liability insurance depends on it, to say the least.

Placing these units in the same relationship/position as your existing cabinets is incorrect.  You really need a knowledgeable professional to get the results you desire and to make full use of the funds you have committed to the project.

I DO think you have made a good choice on the speakers, though.

[Stephen Patterson]

Stephen...

The best placement for these (150 degree) speakers is a single line right in the middle of the space.  JBL should have some papers on this.  But most importantly:

You MUST have the properly certified flying hardware and you MUST have the installation done by a licensed, bonded contractor who is fully qualified to do such work.  THIS IS NOT A DIY SITUATION.  The validity of your liability insurance depends on it, to say the least.

Placing these units in the same relationship/position as your existing cabinets is incorrect.  You really need a knowledgeable professional to get the results you desire and to make full use of the funds you have committed to the project.

I DO think you have made a good choice on the speakers, though.

Thanks for the help and warning.  I need to see if our contractor (also a member of our church) is licensed for this kind of thing.  He was "guy on ladder."  I didn't realize that could impact insurance though - thanks!  Other speaker hadn't shipped so I was able to cancel.  I always saw two speakers in photos online but thought that might be the wrong setup after reading on here.

I think I hit a dead end if it needs to be lower than ceiling level.  People who sign checks don't want anything to be in front of the window.  Do you see any problem with mounting it right at the top in the middle?  Otherwise, I think we'll have to explore other speakers.

Much appreciated.

[g'bye, Dick Rees]

Thanks for the help and warning.  I need to see if our contractor (also a member of our church) is licensed for this kind of thing.  He was "guy on ladder."  I didn't realize that could impact insurance though - thanks!  Other speaker hadn't shipped so I was able to cancel.  I always saw two speakers in photos online but thought that might be the wrong setup after reading on here.

I think I hit a dead end if it needs to be lower than ceiling level.  People who sign checks don't want anything to be in front of the window.  Do you see any problem with mounting it right at the top in the middle?  Otherwise, I think we'll have to explore other speakers.

Much appreciated.

I can't say for absolute sure, but placing speakers in close proximity to reflective surfaces (boundaries) can produce some unwanted effects, thus minimizing  or decreasing the effectiveness of your setup.  The blunt statement is "do it right or don't do it at all". 

Considering the relatively large amount of visual space taken up by the existing speakers, I really can't see how smaller, narrower CHURCH WHITE speakers would detract more than the ugly boxes that are there now.  It's all about compromise, and if crystal clear sound for the service is the objective, then some give-and-take will have to occur.

Unfortunately, it's rather labor intensive to "try it and see".

Good luck getting any consensus out of a large group of people, even if you can prove your point beyond any reasonable objections.  I have one church I did where the oldest member of the congregation kept insisting that the money they paid me to upgrade their system was wasted, since the seat she sat in (the farthest corner in the rear of the Sanctuary) was "her seat" and she would never leave it to move to a seat where she could actually hear...which was unlikely because she was also quite deaf.

[Stephen Patterson]

I can't say for absolute sure, but placing speakers in close proximity to reflective surfaces (boundaries) can produce some unwanted effects, thus minimizing  or decreasing the effectiveness of your setup.  The blunt statement is "do it right or don't do it at all". 

Considering the relatively large amount of visual space taken up by the existing speakers, I really can't see how smaller, narrower CHURCH WHITE speakers would detract more than the ugly boxes that are there now.  It's all about compromise, and if crystal clear sound for the service is the objective, then some give-and-take will have to occur.

Unfortunately, it's rather labor intensive to "try it and see".

Good luck getting any consensus out of a large group of people, even if you can prove your point beyond any reasonable objections.  I have one church I did where the oldest member of the congregation kept insisting that the money they paid me to upgrade their system was wasted, since the seat she sat in (the farthest corner in the rear of the Sanctuary) was "her seat" and she would never leave it to move to a seat where she could actually hear...which was unlikely because she was also quite deaf.

True.  Thanks again for your help.

[Tom Young]

Asymmetrical appeals to us since current speakers are loud up front and inaudible in the back.  Room is 65' wide, 90' deep.  Just ordered another 70J yesterday (then found this forum today).

I think you are confused about what "asymmetrical" means.

I'm looking for placement suggestions.  My current plan is to mount them directly on the rafter at the ceiling with a good downtilt (above where the old speakers are currently hanging).  I'd like to avoid hanging them down if possible.  (Speakers on the wall are old/dead but 13ft as a ref point).  Appreciate any suggestions.

I cannot be sure, but it looks like hanging the CBT 70J's at that height in this space will result in not enough vertical (front-to-back) coverage.

The ideal position for CBT's (and most column loudspeakers) is with the center of the column between seated and standing height. In other words: fairly close to the floor.

Because the CBT 70J's are asymmetrical (the vertical coverage is tilted downwards, slightly), a few feet higher is possible.

Your CBT 70J speakers can be painted to blend in quite well with the wall surface.

Bottom line: use the free JBL coverage/aiming software to check your vertical coverage.

[Jerome Malsack]

With the JBL information you can see about a draftsman to do a scale drawing on the floor plan and the vertical plane for the speakers coverage to help sell the plan. 

It might be very old school to use some graph paper to create the same plans. 

[Brad Weber]

http://www.jblpro.com/products/installed/cbt/downloads.html  JBL provides this software to assist with locating and aiming the speakers.  It is limited to looking at only the vertical plane and only the direct sound, but should help you get some idea of the predicted results with different mounting heights and different vertical aiming angles.
 
I believe that the comments on the locations in plan and one or two arrays may relate to the fact that if the use is primarily speech then a mono system is often the preferred option.  The CBT 70J-1 has a very wide horizontal pattern, in many cases greater than 180 degrees up to and through vocal/speech frequencies, thus for a mono system it is rare when more than one array is appropriate for maximum intelligibility.

[Stephen Patterson]

http://www.jblpro.com/products/installed/cbt/downloads.html  JBL provides this software to assist with locating and aiming the speakers.  It is limited to looking at only the vertical plane and only the direct sound, but should help you get some idea of the predicted results with different mounting heights and different vertical aiming angles.
 
I believe that the comments on the locations in plan and one or two arrays may relate to the fact that if the use is primarily speech then a mono system is often the preferred option.  The CBT 70J-1 has a very wide horizontal pattern, in many cases greater than 180 degrees up to and through vocal/speech frequencies, thus for a mono system it is rare when more than one array is appropriate for maximum intelligibility.

Thanks everyone for the input.  At this point, I think we're going to test the one 70J at a few different heights/places and see how it goes.  Luckily, I only have to sell 3 people on it.

On the calculator, I get good coverage (pretty even levels) at 12-18 feet with some downtilt.  Maybe I'm missing something on there?  I think lower would be better if our front row (10ft away) was farther from the speakers.  Room is 65w x 90d... seating area starts 10 feet from the front and goes to 60 feet from the front.

[Tom Young]

On the calculator, I get good coverage (pretty even levels) at 12-18 feet with some downtilt.  Maybe I'm missing something on there?  I think lower would be better if our front row (10ft away) was farther from the speakers.  Room is 65w x 90d... seating area starts 10 feet from the front and goes to 60 feet from the front.

Trust me.....the front seats will be fine. I've got these in a sanctuary where the nearest seat is closer (than your 10") and it "works", both near to the speakers and at the rear.

And at 15'-18' above the floor you may not be covering all seats with the provided vertical coverage versus the seating depth.

Why mount them higher and tilt them down ? When perpendicular (not tilted), the vertical coverage is tilted down enough that 54" to the bottom of the CBT70J (from the floor) works quite well. And when mounted to a wall they look better (they stand out less) when not tilted.

One of the cool things about this speaker is that you can experiment and try both the 20 and 40 degree vertical patterns.

[Stephen Patterson]

Trust me.....the front seats will be fine. I've got these in a sanctuary where the nearest seat is closer (than your 10") and it "works", both near to the speakers and at the rear.

And at 15'-18' above the floor you may not be covering all seats with the provided vertical coverage versus the seating depth.

Why mount them higher and tilt them down ? When perpendicular (not tilted), the vertical coverage is tilted down enough that 54" to the bottom of the CBT70J (from the floor) works quite well. And when mounted to a wall they look better (they stand out less) when not tilted.

One of the cool things about this speaker is that you can experiment and try both the 20 and 40 degree vertical patterns.

Thanks Tom.  I'll try that, too.  I agree, I think it'd look a lot better.  Glad to hear it works well in a real life application.

side note - I found 30 yr old JBL 4612s behind those grills.  Hooked them up just to test.  Even they sound better than our flown speakers.  Not sure what's wrong with those.  We don't know what's inside the boxes (no record).  They're bi-amped with a DBX Driverack PA (configured for the room).  Guess I'll find out when they come down.

[Ivan Beaver]

side note - I found 30 yr old JBL 4612s behind those grills.  Hooked them up just to test.  Even they sound better than our flown speakers.  Not sure what's wrong with those.  We don't know what's inside the boxes (no record).  They're bi-amped with a DBX Driverack PA (configured for the room).  Guess I'll find out when they come down.

It could be as simple as there is ONE speaker on each side (the old JBLs) as compared to TWO speakers (current) that are more than likely causing lots of interference with each other-lowering the quality.

In audio-the LEAST number of speakers you can do a job with-the BETTER.  You want as few sources as possible-so there is less of a chance for interference.  More IS NOT better.

[ProSoundWeb Community]