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[Lance Rectanus]

Stereo in your application is pretty much a myth for several reasons.  Buy one speaker, a USB-p and you're set with minimal $$$$.

I've been looking for an excuse to buy a Peavey USB-p!

Hopefully, I've attached a picture of my proposed installation: the white rectangle is the "screen" and the black rectangles are the speakers. Dick, if you don't mind, would you please expand on why stereo is a myth for this type of situation. I know that perfect stereo only exists in a couple of "seats", but it seems to me that two speakers would reproduce certain sound effects better than a single speaker would. If I wouldn't gain anything by using a L&R setup, would you suggest that the single speaker be mounted below the center of the screen? I'm thinking that center/above would spray too much sound over the whole ceiling.

[David Allred]

I've been looking for an excuse to buy a Peavey USB-p!

Hopefully, I've attached a picture of my proposed installation: the white rectangle is the "screen" and the black rectangles are the speakers. Dick, if you don't mind, would you please expand on why stereo is a myth for this type of situation. I know that perfect stereo only exists in a couple of "seats", but it seems to me that two speakers would reproduce certain sound effects better than a single speaker would. If I wouldn't gain anything by using a L&R setup, would you suggest that the single speaker be mounted below the center of the screen? I'm thinking that center/above would spray too much sound over the whole ceiling.

Stereo for watching a movie is REALLY important to most people.  Pre-schoolers and maybe older probably don't know or care.  I would argue that sound quality is not THAT important.  Comb filtering?  Again, probably... who cares.  2 speakers, spread, will give you more coverage and more even volume at lowers levels.  I would imagine low volume is what you want most of the time.

[Chrysander 'C.R.' Young]

My $0.02 -

Since you are on a budget and you needs are very modest, I would take a different tactic:  I would forgo powered speakers.  You would have to run AC power to them and figure out some way to remotely power them on and off easily.  This is not cheap.

A small mixer, power amp, and pair of speakers new or scoured off CL or the 'Bay could be had and pressed into service easily and cheaply.  There are a plethora of small PA cabs that can be wall mounted easily and aimed (EV SX series, Peavey PR series, to name just two).  CL around these parts abounds with older, but very capable, used speakers, powered mixers, and the like.

As stated, this is just my $0.02.  YMMV. 

[Luke Geis]

Stereo is cool no doubt, but there are just certain times where it just doesn't matter. This sort of falls into that category. I also don't like the idea of lots of speakers on stands around children. As for coverage, all that can be done is to go by the specs. Without actually measuring or seeing a good plot who knows, but it should be at least somewhat accurate to the stated spec.

What is less understood is that the coverage listed in the specs only pertains to the horn portion of the speaker. So while it may be 60* nominal, it will only be so for frequencies above the crossover point. So yes it is not accurate to say that the simple number is it, but at least knowing what that number means helps narrow it down to a reasonable level of expectation. 60* is less than 90* and if the speakers have the same relative crossover point and horn size ( which is rather likely ) then you can at least half expect the coverage to follow the listed spec with an exceptable degree. When things are mission critical, then it might matter more.....

[Lance Rectanus]

Stereo is cool no doubt, but there are just certain times where it just doesn't matter. This sort of falls into that category. I also don't like the idea of lots of speakers on stands around children. As for coverage, all that can be done is to go by the specs. Without actually measuring or seeing a good plot who knows, but it should be at least somewhat accurate to the stated spec.

What is less understood is that the coverage listed in the specs only pertains to the horn portion of the speaker. So while it may be 60* nominal ...

Safety is the main reason for upgrading to a permanently installed system: too many wires and tripod legs for people to trip over. Plus, it is too time confusing and difficult for the average person to set up (speakers + projector + laptop).

I was studying the polar patterns for the Turbosound iX12 and the coverage doesn't match the published spec until it goes above 1000 Hz in the horizontal. The vertical plots have some really weird interference/cancellation things going on above 1200 Hz. In both plots everything below 500 is pretty much omnidirectional. Its almost as if you need a physically larger device to control as you go lower. Hmmm - sounds like I've heard that before!

Thanks to all for your interaction on this project. I haven't decided which way I will go, but I do feel more informed on the subject.

[Luke Geis]

general rule of thumb is that anything from about 250hz down is essentially omni directional. This changes based on several factors, but in general you can count on that as being true. The speaker is directional to some degree above that point. As I mentioned the stated spec coverage of a speaker will not occur until you reach frequencies that are present in the horn which are of course at or around the crossover point. In this case 1000khz. The most typical crossover points set around 1.2 -1.6khz while some speakers set theirs around 2.1khz. 1khz in any speaker is fairly directional regardless of crossover or horn loading but it would not follow the vertical and horizontal coverage's stated in most specs. I.E. It will be X deg. in directionality in both the Vertical and Horizontal directions. The horn of the speaker is what will give a nominal 90* X 50* spec. Which may explain why there is a weirdness to the 1khz area withe the Turbosound. The horn is likely interacting with the woofer.

Back on point though. Yes, ideally you would prefer to utilize the pocket space that you noted in your picture. In which case two speakers would yield a nice stereo sound and cover the room rather well. As an added bonus, you will keep wires and any stands out of the path of children. This being the case any of the speakers listed above will still do the job magnitudes better than the Fender passport system does.

While others may say that passive is an easier task, you will have a very tough time beating the powered versions. You have to run a cable to the speaker anyway, so how bad is it run two? The level of DSP and technology that is put in powered speakers these days just can't be overlooked. They perform VERY WELL and often are set to a degree of performance better than most sound people are capable of acquiring.

[Jean-Pierre Coetzee]

general rule of thumb is that anything from about 250hz down is essentially omni directional. This changes based on several factors, but in general you can count on that as being true. The speaker is directional to some degree above that point. As I mentioned the stated spec coverage of a speaker will not occur until you reach frequencies that are present in the horn which are of course at or around the crossover point. In this case 1000khz. The most typical crossover points set around 1.2 -1.6khz while some speakers set theirs around 2.1khz. 1khz in any speaker is fairly directional regardless of crossover or horn loading but it would not follow the vertical and horizontal coverage's stated in most specs. I.E. It will be X deg. in directionality in both the Vertical and Horizontal directions. The horn of the speaker is what will give a nominal 90* X 50* spec. Which may explain why there is a weirdness to the 1khz area withe the Turbosound. The horn is likely interacting with the woofer.

Back on point though. Yes, ideally you would prefer to utilize the pocket space that you noted in your picture. In which case two speakers would yield a nice stereo sound and cover the room rather well. As an added bonus, you will keep wires and any stands out of the path of children. This being the case any of the speakers listed above will still do the job magnitudes better than the Fender passport system does.

While others may say that passive is an easier task, you will have a very tough time beating the powered versions. You have to run a cable to the speaker anyway, so how bad is it run two? The level of DSP and technology that is put in powered speakers these days just can't be overlooked. They perform VERY WELL and often are set to a degree of performance better than most sound people are capable of acquiring.

Regarding the running two cables vs one, for an fixed install I would honestly just make up or get made up a siamese cable with power and signal together, I have had no issue running mic level through a decent XLR cable next to power cables, I doubt line level will have any issue.

Just make sure you follow code when you select the cabling and correctly install it.

[Ivan Beaver]

Stereo for watching a movie is REALLY important to most people. 

But ONLY if they are within the stereo image.  In a larger room, most people are NOT in the stereo image.

And unless EACH speaker covers the ENTIRE seating area BY ITSELF, stereo is NOT a good idea.  This is because people who are out of the coverage of the "other" speaker will not be getting the information provided by that speaker.  ie they will be missing parts of the music or dialog.

When looking at a sound system for a large area, stereo is usually NOT the way to go.  There are exceptions, but they are rare.

I have done a good number of LCR crossmatrixed systems.  If well designed and ESPECIALLY if well tuned, they can be stunning in every seat.

But if not tuned properly or operated properly, they will REALLY screw up the sound.

[Lance Rectanus]

I pulled the trigger and am going to go with 2 of the JBL Eon 612, the Mackie ProDX4 mixer and the Furman M8-S power sequencer.


The speakers will be mounted roughly 10 feet above floor level and roughly 15 feet apart. Taking Ivan's most recent comments into account, I should be able to cover the intended area (approx. 20' deep x 30' wide starting 10' from the base of the wall where the speakers will be mounted) fairly well with both of these speakers. Again, the intended usage is for pre-schoolers 5 days a week and K-6 kids one day a week for 15 minutes, so my listening audience doesn't have the highest expectations. If we can use the setup for more than this, BONUS!


My thought process, if anyone is interested: I was leaning towards the Turbosound iX12's, but those aren't "expected" in stock for 4 weeks. That tells me that they possibly haven't left China yet, so who knows when they will actually land in the US. On paper the DBR's and ZLX's aren't the equal of the others at the same price point. No one had anything to say negative or positive about any of these speaker options, so I will report back with my experience.

[Michael Lascuola]

Although it's probably too late, and may have been only my experience, ordering "not yet in stock" Turbosounds from Sweetwater got iX and iQ boxes in my driveway faster than an average eBay order for something that *was* in stock.

YMMV, of course.

[ProSoundWeb Community]