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[Ivan Beaver]

Ivan, measurement is a whole 'nuther topic.

To get back to the topic, if you can produce data that shows that your stick system can perform well enough in a given situation, I'm all ears.  But I'm not a fan of using destructive interference to attack a point made in good faith.

What sort of data are you looking for? The website gives the basic information.

Generally the best way to determine "suitability" (coverage-SPL-freq response et) is to model the speaker in question.  This is easily done via the free Direct software.

Maybe you are looking for something else.  What would that be?  And do other manufacturers offer this as well that give you more information

The FIRST and most important aspect of "performs well enough in a given situation", is to determine WHAT that situation requires and what sort of performance you are ACTUALLY looking for.

A SIMPLE SPL number (with no weighting or time) is kinda useless.

For example here are some numbers from my show last night.

This was the warm up act-I did not stay the whole time-but am QUITE SURE it got quite a bit louder after I left-there were still 4 hours left in the show.  The full range system still had around 10-15dB headroom (before limiters) in it when I left.  The subs were probably a bit less than 10dB left.

This was measured with a NTI XL2 meter.  It is good to 144dB.

FOH was around 125' from the stage.  The rear wall was around 240' from the stage.  Venue capacity was 5000, but maybe half full when I left.

I measured this during the first 2 acts over a variety of songs and it was pretty consistent.

Here is what I was measuring at FOH.

A slow was around 103dB.  A peak was around 112-114dB.

C slow was around 120dB.  C peak around 130-133dB

The actual freq response was a typical low freq "haystack".

Below 100Hz was typically 40dB higher than above 200hz.

Most of the music was centered around 50Hz, but did get down to 25Hz or so at times.  Which was around the same level as 50Hz.

So what number would you say is a "simple SPL" that describes the system loudness and capability?

It really depends on more specifics.  The level below 100Hz had a ratio of 10,000 times that of the rest of the spectrum.

So it was "carrying" a lot of the weight-so to speak.

I'm sorry-but simple answers result in wrong answers in complex situations.

[Jeremy Silverthorn]

Thank you to Ray & the others for their feedback.  First off, I want to clarify something, the 2-man AV team I am a part of work for the client, we are not a rental house & we don't have any other clients. We are a full time AV staff, that throughout the year produces & edits videos for the company, as well as various AV tasks for smaller meetings & events. Then once a year we have this large convention where we are providing, setting up & running pretty much all of the AV gear (we hire out for staging, pipe & drape, projectors & screens & the lighting) but we own a random collection of gear... speakers, wireless mics, mixers, cameras, computers, video switcher, etc. that we cobble together to setup & run this big show.

We purchased the 4 Carvin SOS's & 2 large Carvin speakers 10-15 years ago so we wouldn't have to take down the speakers & amps we use every week in our office meeting rooms!  Through the years the company has purchased various gear, so they wouldn't be renting it every year (the top brass don't get that by renting we can always have newer/better gear though... they finally figured that out after buying a couple sets of video projectors through the years that were never quite up to the task!) Plus they seem to neglect the fact that the gear we do own has a useful life & needs to be replaced at some point!

The speakers are packed away & only get used once a year and sometimes they take a little coaxing to warm up & come to life, so that's why I'm not sure if they may need repair or replacing sometime soon.  I think this year I may just try the two large speakers up front and another set of the smaller speakers down each side of the room on a delay.  (The room we're in this year is long & narrow)  I think adding in the third set will just add to the mess of sound.

I'm still very curious about the stick/sub type system and how that would work for our application... will have to look into renting one of these systems sometime in the future.  Can anyone recommend a dealer/vendor/rental house in S. Florida?  Thanks again

[Don T. Williams]

If the room is long and narrow, the K Array KR202 type system would not be the best for this room.  If the room was "turned sideways" they would probably kick butt.  Look for a higher Q system and delay speakers properly adjusted.

If your existing speaker requires "a little coaxing to warm up"  there is something wrong!  Don't trust them!

[Mac Kerr]

If the room is long and narrow, the K Array KR202 type system would not be the best for this room.  If the room was "turned sideways" they would probably kick butt.  Look for a higher Q system and delay speakers properly adjusted.

If your existing speaker requires "a little coaxing to warm up"  there is something wrong!  Don't trust them!

Has anyone had a good experience with the KR202s? In fairly extensive listening tests and a tryout at a real show, I found them totally unsuitable for every type of use. They are essentially omnidirectional at all frequencies in the horizontal plane and just sound terrible.

There is a great attraction to a very skinny speaker in small rooms, but I have yet to find it. The best I have used so far is the JBL CBT-70J, which is much bulkier than the K-Array and others of that ilk.

Mac

[Ray Aberle]

First off, I want to clarify something, the 2-man AV team I am a part of work for the client, we are not a rental house & we don't have any other clients. We are a full time AV staff, that throughout the year produces & edits videos for the company, as well as various AV tasks for smaller meetings & events. Then once a year we have this large convention where we are providing, setting up & running pretty much all of the AV gear (we hire out for staging, pipe & drape, projectors & screens & the lighting) but we own a random collection of gear... speakers, wireless mics, mixers, cameras, computers, video switcher, etc. that we cobble together to setup & run this big show.

Great to hear the rest of the story. I'm gonna respond in more detail, when I'm not busy trying to flip gear before I get off work tonight!

-Ray

[Art Welter]

[quote author=Jeremy Silverthorn
I'm still very curious about the stick/sub type system and how that would work for our application... will have to look into renting one of these systems sometime in the future.  Can anyone recommend a dealer/vendor/rental house in S. Florida?  Thanks again
[/quote]Jeremy,
I am located in DeLand Florida, between Orlando and Daytona Beach- not South, but not all the way North, and not located in "dizzy world" :^).

I have stick/sub systems and standard cone/HF horn, and multiple driver virtual single point source designs, and subs from small bass reflex to large-ish "tapped horn" designs.

If you are interested in hearing the pros and cons of each, contact me to set up a time- best after December 8 when I will have my own property with adequate space to do some demos without complaining neighbors across the street ;^).

Cheers,

Art
Welter Systems, Inc.

[Speed Daemon]

Has anyone had a good experience with the KR202s? In fairly extensive listening tests and a tryout at a real show, I found them totally unsuitable for every type of use. They are essentially omnidirectional at all frequencies in the horizontal plane and just sound terrible.

There is a great attraction to a very skinny speaker in small rooms, but I have yet to find it. The best I have used so far is the JBL CBT-70J, which is much bulkier than the K-Array and others of that ilk.

Mac

This is what you're going to find with any loudspeaker that doesn't have a baffle, horn or some other mechanism to direct the sound in some way.  Column speakers can at least offer a little baffle, but sticks sacrifice all mechanical advantage for aesthetics.  Whatever directionality they offer on the vertical axis will be centered around one frequency for systems that employ only one type of driver and one spacing interval.  Performance will decrease, and can get downright awful at other frequencies.  This is the kind of thing that we saw in high school physics class with those wave tanks.

The same principles apply to TV and radio broadcast antennas.  The ones that stack simple dipole elements can produce a narrow cone of RF energy that covers a large area, right out to where the curvature of the earth finally blocks the line of sight signal.  But on the horizontal axis, propagation is omnidirectional.  More sophisticated designs can produce a bit of a cardioid pattern, but that's about it. Us old-timers have lots of memories of multipath "ghosting" and "picket fence" interference that is the equivalent of room reverberation in the RF world.

Look at the KR202 spec sheet:

https://www.k-array.com/phocadownload/Products/Portable/KR202/KR202_Datasheet_Ver1_Rev4.pdf

Edit: whoops! there is a stated coverage for both axes.  It can play loud, but it cannot focus the horizontal.  If you're in an open field, and sight lines are of utmost importance, these would be just the thing to use.

[Marcus Baeumler]

...
Look at the KR202 spec sheet:

https://www.k-array.com/phocadownload/Products/Portable/KR202/KR202_Datasheet_Ver1_Rev4.pdf

Note that the coverage for this so-called "line array" is "Omni" on H and V axes.  It can play loud, but it cannot focus.  Whatever line array effect that they purport to have apparently isn't enough that they want to show the plots of it.  If you're in an open field, and sight lines are of utmost importance, these would be just the thing to use.

I think you are looking at the wrong specs.
The sub is shown as omni, the sticks as 110° x 7°-35°.

Not trying to judge how realistic these specs are or in which frequency range they can be achieved.

[Speed Daemon]

I think you are looking at the wrong specs.
The sub is shown as omni, the sticks as 110° x 7°-35°.

Not trying to judge how realistic these specs are or in which frequency range they can be achieved.

Thanks for the correction, Marcus!  I did miss that.  Must have moved that column right out of the frame when I made the PDF big enough for my tired eyes to read.  My bad.

So those numbers aren't bad, but don't tell the story of a SPL/angle of incidence plot, or even better, at a range of frequencies.  That's what I was hoping to see.  Best would be having all that measured by an independent lab with no vested interest in the outcome.  Manufacturer-supplied specs require a grain of salt IMO.

[Don T. Williams]

To answer Mac and others wondering about the KR202, I use them extensively and in the right circumstances, they work very well for me.  As I stated earlier on this thread, they worked so well for a Thanksgiving prayer breakfast last week in a college gym, that I have been offered a series of jobs for that university.  As I also stated in that post, they are not the solution for every event and do not work well for many venues.  They are just one of many tools that I use.  I have a DB Tech T12/T8/T4 line array system, JBL 835P/828P's, a lot of QSC K series products, and other brands of gear.  I just received a quote on DLS SM80/TH118's to add to my "tool kit".  They are all just "tools of the trade".

About the KR202 (and in my case the older KR200's in my rental inventory) specifically, I find they work best in large reverberant rooms with flat seating.  We have a 4400 seat arena here with a large floor.  When events are set up only on the floor, especially when they are "turned sideways", I haven't found anything that works better.  It is much better than the "new" (two year old) house line array in both coverage and sound quality.  I am careful to elevate the system so the center of the "columns" is at the listeners head height.  I usually do this by placing added subwoofer(s) under the KR200 sub.  The added subs also help with louder bass heavy events.

I find the 7 degree vertical coverage doesn't excite the room as much as other speaker types.  I have had no luck using them in the 35 degree position.  I have used them for both indoor and outdoor events for every thing from bluegrass to moderate volume rock groups (with the added subs) with event sizes of up to about 2,000 people.  I also carefully adjusted their angle to match the rake of a grand stand that seated 5K for a school graduation, and again they worked very well.

They have a very wide horizontal dispersion and are surprisingly smooth and even.  They need just a little (but not a lot) of eq to sound their best.  They have several internal eq setting, but I have only found one that works for me, so I leave it on that setting.  The fact that they actually get me jobs speaks highly for the system.  This this is not a function of how unobtrusive they look.  I get jobs because of how well they work.  Demos in churches resulted in four sales in the last two years, but I sold a lot more point and shoot systems and a few line arrays in the same period.  Again it is just one tool that in the right setting can work very well.  Just my opinion, but they are worth a look!

[ProSoundWeb Community]