JBL CBT-1000 Column Array Speakers

[John Renner]

Does anybody have any experience with these?
I have a church where the seating area is 40' wide by 50' deep. Roughly about 150-175 people but room for more. I currently have combing issues with the two R,L hung Yamaha 112iv two ways that we are currently using.

I was thinking that with this speaker, I could center hang it, Ceiling at center is 11'-2" with the sides at 9' , and cover the entire seating section without too much foldback from the back and side walls. I also have a Tannoy sub that is designed to be hung, it's not pretty but might fit above the drop ceiling.(coming through egg crate grid)

According to the specs, this should work, but I don't like having to recommend a single speaker that costs that much for such a small church without knowing it or having heard it. I am just trying to even out the volume throughout.

About the church, we have more of a symphony type of music, NO drums, cymbals, Bass, etc. We do have a violin, Flute, Sax, electric guitar, Piano, an Organ and several trumpets. Sometimes we have two flutes, or two violins, or two saxaphones, but it changes with a roster. Also, the congregation is singing along with the worship leaders, so there is no choir. We try to keep the overall volume in the back at 85db, but in the front with the trumpets, It can go well above. The guitar, was putting out 102db all by itself without any assistance from the PA. Kind of high stage levels .

 

[John Renner]

By the way, I am still awaiting the email to confirm my account. I don't know why I am not seeing it.

 

[Kevin Maxwell]

The Yamaha 112iv don’t look like speakers that are meant to be hung. That is your first problem.

Have you tried tuning off one of the speakers and see how it sounds. Sometimes a problem like you are describing can be helped if one of the speakers are lowered in volume just a little bit. You may have a different problem then you think you have. A Left Right hang will usually have some comb filtering problems but not usually something that anyone would ever notice with music. A center hang is a good idea for the vocals especially speech, but most people don’t like it for music. A Left Center Right hang can solve a lot of problems, if it is setup right.

As to the JBL speaker it may or may not work in your room. But I think it works better when used with more than just the one hung by itself. Isn’t there a companion piece that is meant to hang below it to extend the range to a full range speaker? Your ceiling height isn’t enough in my experience to hang a column speaker in the middle especially if you were to do the proper configuration with that JBL speaker system.

 

[John Renner]

Kevin, Thank you for replying.

No, I have not tried turning off just one of them, I will have to physically unplug them to do that, but I will try it. The reason those speakers got hung, is I was following the theory that the more equal distant the speakers were from front and back, it would help with the overall sound levels. I realize that these speakers are good workhorses but are cheap and not the best fidelity. The room is 50ft wide X 70ft deep Some of the reason I went with a left right hang, is because on the far left, starts the violin, flute, sax, sax, guitar, then along the front from left to right there are the worship leaders, Piano, and podium center of room then on the right, the organ and back on the right side the trumpets.

We are setup for mono going out to the speakers, we have reserved the L+R main outs for the recordings, Video out, Streaming etc. I know this might not be standard, but I've been trying to gain intelligibility and to some degree failing. I have no formal training in audio. But I have been using Yamaha book of audio as a reference.


Yes that JBL speaker does have an extension that can be used, but as I read the usage, is for if there is a balcony, which we don't have. The length of the bottom portion is 40" tall and if put at the peak of the ceiling, would be OK visually IMO. I looked at the CBT-70 Which are 24" tall but I believe I would absolutely need two of them. And that would be just the lower portions as well.

The reason I am looking at the column/Line array type is that
A: I have been getting complaints of volumes too loud
B: I can't hear
C: I can't understand
D: They say they have extremely high intelligibility
E: and not least, because years ago, I had a couple of EV line arrays, that were simply a 6:sqx48" long cabinet with 6- 3x5 speakers rated for 20W probably. I had them at a fairly low volume, and the wave of sound was all encompassing, and even though someone shouted at me from behind about 15ft, I could hardly hear him. But I could hear every detail of the music (Symphonic). So I have already been somewhat impressed favorably with the line array type of speaker.

 

[Rob Timmerman]

The reason I am looking at the column/Line array type is that
A: I have been getting complaints of volumes too loud
B: I can't hear
C: I can't understand
D: They say they have extremely high intelligibility

+1 on the note that your current speakers don't appear to be designed to be flown, and so are probably unsafe if they are currently flown.

I've used the Yamaha Club series, and they are decent boxes for the price. While you can certainly do better, I don't think that's the root cause of your issues.

If you're really targeting 85dB at the back for speech, I'd agree with the people who think it's too loud. Lowering the level can help with intelligibility in reverberant spaces, and make it easier to listen to. Plus, there's generally less distortion from the loudspeakers (as they aren't working as hard). If the issue is with the music, I'd start with the arrangements and the levels of the individual instruments. If the stage volume isn't under control, you're fighting an uphill battle getting vocal intelligibility.

How does the system sound with playback?

 

[John Renner]

Rob, I get the safety concern thank you for answering.

I have supported them with Kindorf/Unistrut from on top of the ceiling joists, screwed to the top of these joists. Then a double nutted 3/8" threaded rod comes down through the drop ceiling to another piece of Kindorf which in turn is screwed to the top of the speaker cabinet. From that top kindorf, there are two 3/8" threaded rods down each side of it to the bottom kindorf which is also screwed to the bottom, (to keep it angled and not sliding out) and double nutted again and the rods cut short. It's not the prettiest, but It has been there several years without loosening.
This speaker isn't that heavy, maybe 35lbs. When you consider that an 8/32 screw is rated at 40lbs, I trust this is safe enough. We are not in a normally earhquake area such as California. I am not a rigger, but I have worked in commercial construction and believe in overbuilding if I can.

But I know that could be construed as just being defensive, and I don't mean to be coming across that way. If I am wrong let me know - Please.

Decibels, No, we are not targeting 85 at the back, (especially for speech) we are using that as a MAX during worship, all instruments, all singing, and someone at the pulpit calling out words. for instance. The Speech range usually is from 65-75 Db

To mitigate stage volume, which was quite loud, and as you say, not under control, The guitar was mic'ed for overflow and recording, and had a marshall amp (2-12's), I have just changed the guitar amplifier to be a Mackie MK8 with a stomp box for some reverb, tonal control, and put it within 2' of the players head. Now he will play to his own volume, with a direct box instead, but now I have to put the guitar over the PA. Yesterday we tried that, and it seemed to work well.

We are going over the recordings now, to see if that changed the bleed-over into my other microphones and get some feedback from the musicians. The one of the guitarist says that in his opinion, the sound is better. Time will tell.


As far as how does the system sound with playback, what do you mean? with a commercial CD? or playing back what was recorded here?
Playing back what was recorded here, sounds pretty much like it was played to me. Younger ears are beginning to take over and I have to trust them to set what sounds proper. I cannot hear above 9khz, so I get some flack for that. Construction ears.

I just want to hand over the system with as few troubles as it is within my power to do.

 

[John Renner]

One last thought, other than the guitar, given the current layout, I don't know how to get trumpets or saxaphones to play softer. With the exeption of the Organ, Piano, and Guitar, all the instruments are the individuals I can't really ask them to switch to electronic versions as that request would be widely unpopular.

What I dont show on the drawing, there are two exit doors at the back of the stage area, and on either side, and office door that does get used. Where it says worship leaders" is a handicap ramp, and behind the pulpit and organ is a baptistry. pool.

 

[Rob Timmerman]

As far as how does the system sound with playback, what do you mean? with a commercial CD? or playing back what was recorded here?
Playing back what was recorded here, sounds pretty much like it was played to me. .

The idea here is to separate out impact of the "mix" from the system evaluation. Personally, I'd use something commercially available that I was familiar with how it's "supposed" to sound.

 

[Kevin Maxwell]

One last thought, other than the guitar, given the current layout, I don't know how to get trumpets or saxaphones to play softer. With the exeption of the Organ, Piano, and Guitar, all the instruments are the individuals I can't really ask them to switch to electronic versions as that request would be widely unpopular.

What I dont show on the drawing, there are two exit doors at the back of the stage area, and on either side, and office door that does get used. Where it says worship leaders" is a handicap ramp, and behind the pulpit and organ is a baptistry. pool.

Where are you located? Maybe someone local to you can stop by and lend a hand.

Are the horns mic-ed? I have been surprised at how some people can’t hear themselves on a stage. I have had trumpet players bring a clear Plexiglas disk that they put on the mic to reflect the sound of the trumpet back to themselves. I have seen sax players use the same thing but it doesn’t make any sense to me because the mic is aimed down and not reflecting back to the player. So you may get them to play softer if you can put a piece of Plexiglas in front of them reflecting back their sound to them.

Keep in mind one sound recommendation, just because there is a mic on something doesn’t mean it has to be turned up. Sometimes a player will think they have to play loud because they don’t have a mic on their instrument. Some instrumentalists can only play loud, they were never taught how to play properly. There have been many times I have wanted a device to put on a horn that will decrease the volume without affecting the tonality, I don’t know of one that exists.

I am curious what your sound system consists of and how it is configured. There are a lot of tricks and techniques for good or at least better sound and that is why there are books and schools that teach this stuff. A forum post isn’t going to answer all of you questions, but can help with specific questions.

You are trying to do sound reinforcement. That means in most places, especially like the one you are in that some things will carry without any amplification and some things will need amplification. You need to blend the two together. That is one reason why when someone asks me to record the output from the mixer (the House mix) I tell them no because it will sound out of balance. An instrument that is loud on stage and doesn’t need to be up in the house mix will then be missing from the recording.

At one outdoor concert we were setting up for the bass player and the guitar player showed up before we were done setting up and plugged in and started to wail away. This was a Doo-Wop group. We told them to just play loud enough so that they could hear themselves and let us bring it up to the level it needed to be for the audience. And remarkably they listened and did that. After the show all of the band members came up to us and said “we never heard ourselves so well”. Their groupies came up to us and said "they never sounded so good". If the musicians cooperate it can make a huge difference.

 

[John Renner]

Rob, Thank you for the explanation. I don't usually listen to much commercially available work so I will have to find some that would be adequate to test with.


Kevin. I am in Connecticut pretty much center of the state. Right alongside the Connecticut River.
The Horns are mic'ed but do not go into the reinforcement part of the PA, it is only for recording and other ante rooms. There is one mic right at the corner of the organ, and closest to the #1 trumpet but generally pointed at all of them. It is about 6ft away. Kind of like a choir mic would be.

Pretty much all of the instruments are mic'ed so thinking I can't be heard shouldn't be the issue. The Trumpets, Organ, and saxes are not going over the reinforcement PA. Just for outbound mixes.


I did change out the guitar amp with the mackie MK8 active monitor and close to the guitar I saw a drop of about 25-30 Db. So that is good. The rest of it sounds much quieter now, but I do feel like I am slightly straining to hear in the back. Now my issue is simply on the trumpet's side. I like the Idea of the plexiglass to reflect sound back to the trumpets, I will see if I get any flack from that idea from the pastor. It would be a fairly cheap fix and better than using mutes.

 

[Kevin Maxwell]

Rob, Thank you for the explanation. I don't usually listen to much commercially available work so I will have to find some that would be adequate to test with.


Kevin. I am in Connecticut pretty much center of the state. Right alongside the Connecticut River.
The Horns are mic'ed but do not go into the reinforcement part of the PA, it is only for recording and other ante rooms. There is one mic right at the corner of the organ, and closest to the #1 trumpet but generally pointed at all of them. It is about 6ft away. Kind of like a choir mic would be.

Pretty much all of the instruments are mic'ed so thinking I can't be heard shouldn't be the issue. The Trumpets, Organ, and saxes are not going over the reinforcement PA. Just for outbound mixes.


I did change out the guitar amp with the mackie MK8 active monitor and close to the guitar I saw a drop of about 25-30 Db. So that is good. The rest of it sounds much quieter now, but I do feel like I am slightly straining to hear in the back. Now my issue is simply on the trumpet's side. I like the Idea of the plexiglass to reflect sound back to the trumpets, I will see if I get any flack from that idea from the pastor. It would be a fairly cheap fix and better than using mutes.

The center of the state, is this just below Hartford or are you actually in Hartford? I’m also in CT I am in Fairfield, about 50mile from the dead center of CT. What kind of church is this? Do you have a list of what equipment you are using? I ask for the equipment list because it helps me to understand what you have to work with and if I am familiar with it I should also know the capabilities. If you want to PM me your phone number maybe we can talk. You can also PM me the equipment list in case you don’t want to post that publicly.