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[Jerome Malsack]

Crown amp is XLS  and is not setup for the first option  Parallel to operate into lower Ohms ratings. 

http://www.crownaudio.com/media/pdf/legacy/133465-6.pdf

[Brad Weber]

Unless what I have done something very wrong in having 5 on a channel of a crown xls 402. I know the ohm load is wrong it should only be 4 speakers, but it is the best I can manage right now. Sound quality while just playing a keyboard is not clear. The speakers seem to be bad and most likely should be not considered as usable going forward. Maybe the design is good and relevant and just should have the proper speakers installed.

 I am going to get pictures tonight and will include one of the ceiling layout. I hope that will give a complete overview of this. I was originally hoping to use the existing speaker system but discovered it is the biggest problem.

The original setup may have had the 10 total speakers wired in some series-parallel fashion that presented a total 4 Ohm or greater load to the amp, which is also why it then ran into one channel.  That would make sense in terms of the impedance and the power ratings and it should have worked fine.
 
Assuming you rewired the speakers to apparently have five speakers wired in parallel on each amplifier channel then that may have done two things.  First, it could have resulted in a 1.6 Ohm nominal, and possibly even lower at some frequencies, impedance per channel, which is less than the amplifier is rated to drive.  That could stress the amplifier.  Second, by lowering the impedance and using two channels you're now running more power into half as many speakers so it may be overpowering the speakers.  You can turn down the front panel attenuators on the amp to attenuate the inut signal, but that does not reduce the potential output of the amplifier.
 
So the system may not have been working properly but the changes made don't necesssarily seem to be ones that would improve the situation.
 
 
You also made a comment earlier about one of the concerns with the existing system being some coverage issues.  If you install a new system then you probably want to be pretty confident it will address those concerns and not just provide different but similar results.  That's why it is important to focus on what you are trying to do and how a new system addresses that and not simply assuming that new or different will be better.

[Ivan Beaver]

You also made a comment earlier about one of the concerns with the existing system being some coverage issues.  If you install a new system then you probably want to be pretty confident it will address those concerns and not just provide different but similar results.  That's why it is important to focus on what you are trying to do and how a new system addresses that and not simply assuming that new or different will be better.

Yeah-the best way to insure coverage is to  get suggestions from people who do not know the situation/budget etc from the internet-so it must be true-------------------

As with any project you have to define the target-and that includes budget.

THEN and only then-can you start to get decent suggestions.

[Cyrus Masters]

Yeah-the best way to insure coverage is to  get suggestions from people who do not know the situation/budget etc from the internet-so it must be true-------------------

As with any project you have to define the target-and that includes budget.

THEN and only then-can you start to get decent suggestions.

   I think I have enough info to describe the current situation to launch from. Right now the system is powered by a Crown xls 402 amp running two channels into a csi sds-8 speaker distribution block one speaker wire to each individual speaker of five 20 watt, 8 ohm Sound Advance CT-8 speakers per channel. Please note they do not have transducers to change how they could work.

 
distibution block


ceiling





Each photo should be clickable to open larger in your browser from photo bucket. There are a  couple more that are viewable there as well. On the second page of this thread I attempted a simple paint image to display the floor plan. Just ask if I am missing anything more.

  This is what it is. Instead of asking for speaker suggestions, a better question is what could or should be done to improve on this? Even if it costs 700 bucks great; that is a wish not real. 1,800 is also doable right now with out going to raise aditional money. So if the solution is surprising simple great, if it requires more then the 1800 on hand at the moment it will just have to be completed next quarter.

 Giving the volume levels from the list http://www.industrialnoisecontrol.com/comparative-noise-examples.htm , I would say the average volume would be 60-70db. I doubt there woud ever be a need to hit 80 unless I am there left by myself..

[Cyrus Masters]

The original setup may have had the 10 total speakers wired in some series-parallel fashion that presented a total 4 Ohm or greater load to the amp, which is also why it then ran into one channel.  That would make sense in terms of the impedance and the power ratings and it should have worked fine.
 
Assuming you rewired the speakers to apparently have five speakers wired in parallel on each amplifier channel then that may have done two things.  First, it could have resulted in a 1.6 Ohm nominal, and possibly even lower at some frequencies, impedance per channel, which is less than the amplifier is rated to drive.  That could stress the amplifier.  Second, by lowering the impedance and using two channels you're now running more power into half as many speakers so it may be overpowering the speakers.  You can turn down the front panel attenuators on the amp to attenuate the inut signal, but that does not reduce the potential output of the amplifier.
 
So the system may not have been working properly but the changes made don't necesssarily seem to be ones that would improve the situation. 

 I know I have not been able to correct things properly, yet. The way it was, was the system was shoe horned into the pulplit. one amp channel ran the house the other channel powered a couple monitors. A balanced mic line was run back into the sound room and patched into the speaker block to run all 14 speakers in the nursey, foyer and worship hall.

[Ivan Beaver]

A balanced mic line was run back into the sound room and patched into the speaker block to run all 14 speakers in the nursey, foyer and worship hall.

So now there are 14 speakers hooked to the amp.  What are the monitors hooked to if you are using both channels for the ones in the sanc.

Are there any volume controls for the other areas?

Are you sure there are no "impedance compensation" resistors behind that patch panel?

[Cyrus Masters]

So now there are 14 speakers hooked to the amp.  What are the monitors hooked to if you are using both channels for the ones in the sanc.

Are there any volume controls for the other areas?

Are you sure there are no "impedance compensation" resistors behind that patch panel?

 14 speakers were on one channel, I tried to reduce the load by dropping the monitors, foyer, nursery speakers. Now I have 5 to a side of the amp It did make an improvement in the room sound, but it is still not right. I did lower the input levels of the amp when I did this to about 1/4 of full but I may still have an overdrive problem. The is a volume control in the foyer for the foyer and the same in the nursery.

 Here is some information on the speaker distribution block. It is an unpowered device so I am unsure how it would maintain impedance
http://www.worldeyecam.com/store/speco-csi-sds-8-8-pair-speaker-distr.html

CSI SDS-8 8 PAIR SPEAKER DISTRIBUTION

  The SDS-8 is a speaker distribution center which is manufactured by Speco to accommodate up to 8 pairs of speakers. The SDS-8 distribution center comes equipped with a 1 channel input, 4/8/16 ohm impedance maintenance, a 300W max power, as well as a 100W RMS power, and a rack mountable black metal housing. The SDS-8 distribution center also consists of a lightweight size, and comes easy to use for all operators to help save money.

Features:

•8 Pair Rack Mount Stereo Speaker Selector

Specifications:

•Audio Output : 8 Speaker Pairs
•Channel Input : 1
•Dimensions : 3-1/4"(H_ X 1-1/2"(W) X 15"(D)
•Housing : Black Metal Rack Mountable
•Maintains Impedance : 4,8,16 Ohm
•Max Power : 300 Watts
•RMS Power : 100 Watts

[Ivan Beaver]

14 speakers were on one channel, I tried to reduce the load by dropping the monitors, foyer, nursery speakers. Now I have 5 to a side of the amp It did make an improvement in the room sound, but it is still not right. I did lower the input levels of the amp when I did this to about 1/4 of full but I may still have an overdrive problem. The is a volume control in the foyer for the foyer and the same in the nursery.

 Here is some information on the speaker distribution block. It is an unpowered device so I am unsure how it would maintain impedance
http://www.worldeyecam.com/store/speco-csi-sds-8-8-pair-speaker-distr.html

CSI SDS-8 8 PAIR SPEAKER DISTRIBUTION

  The SDS-8 is a speaker distribution center which is manufactured by Speco to accommodate up to 8 pairs of speakers. The SDS-8 distribution center comes equipped with a 1 channel input, 4/8/16 ohm impedance maintenance, a 300W max power, as well as a 100W RMS power, and a rack mountable black metal housing. The SDS-8 distribution center also consists of a lightweight size, and comes easy to use for all operators to help save money.

Features:

•8 Pair Rack Mount Stereo Speaker Selector

Specifications:

•Audio Output : 8 Speaker Pairs
•Channel Input : 1
•Dimensions : 3-1/4"(H_ X 1-1/2"(W) X 15"(D)
•Housing : Black Metal Rack Mountable
•Maintains Impedance : 4,8,16 Ohm
•Max Power : 300 Watts
•RMS Power : 100 Watts

I don't know about this one-but I have seen similar products that just have a series resistor with the terminals.  So no matter how many speakers are hooked up-then they are still in series with the resistor (the 100 watt RMS rating is my reasoning) so the load is not as low as one would think on the amp.

[Tim Perry]

Why not get a couple QSC K-12  (or similar) , put them on tripod stands left and right. Hook then up and go.

After a couple weeks they will effectively turn invisible. No one looks at speakers except other sound guys.

[Tim Perry]

I don't know about this one-but I have seen similar products that just have a series resistor with the terminals.  So no matter how many speakers are hooked up-then they are still in series with the resistor (the 100 watt RMS rating is my reasoning) so the load is not as low as one would think on the amp.

My guess would be that this thing switches speakers into series/parallel  depending on how many button are pushed.

[ProSoundWeb Community]