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FredT
07-19-2009, 02:34 PM
This a follow up to a thread that was posted a few months ago. The original thread can be found here: http://techtalk.parts-express.com/showthread.php?t=209376

I had long since sold the last pair of Art Arrays when Howard, the owner of the prototype pair, posted this message, and Pete Schumacher graciously offered a revised and improved crossover design that was intended to attenuate some response anomalies and also to reduce the tweeter's distortion. I had no plans to build another pair, but my sons gave me a large PE gift certificate for Father's day, and I ordered the parts to build another pair with both the old first order and Pete's revised 2nd order woofer / 3rd order tweeter crossovers.

If I may digress a moment, I'm a hard core line array fan. My main speakers are Selah Audio XT-8 arrays, and almost everybody who has heard a good pair of line arrays such as the XT-8's or Danny Ritchie's latest LS-9 design would agree they are impressive. On the other side of the spectrum, many diy'ers have built budget line arrays using buyout drivers, and these are inexpensive to build and fun to listen to. When designing the Art Arrays I was looking for something in between, costing far less than the Selah or GR Research arrays but offering better quality drivers than the buyout arrays, and especially drivers that would continue to be available in the future.

The Art Arrays are described in the above referenced thread so I won't repeat all that. The important characteristic of these speakers is that they offer a good taste of line array sound for under $500. Instead I'll summarize the difference between the original crossover and the one that Pete designed.

First, the difference isn't as great as I would have expected. My first reaction was that there seemed to be no difference. Then, upon listening carefully to some jazz tracks with brushes sliding across cymbals I noticed the sound was more like "sssssssssss" with Pete's crossover versus "SHSHSHSH" with the first order. I also noticed on the Dorian recording of Mussorgsky's Pictures at an Exhibition performed on a large pipe organ, there was more treble distortion when played loud, especially with a Krell solid state amp driving the speakers. Finally, after listening to Pete's crossover for a couple of days I switched back to the original design and perceived a slightly "shouty" sound with the originals, much like the experience of switching from a high end two way speaker to the typical Fostex-based single driver speaker.

I disassembled the speakers last week to finish the enclosures, and I reassembled them using 12 ga Belden 5000 series cable versus the 16ga Wal Mart auto dept zip cord I had used originally, and the treble resolution increased significantly along with a corresponding reduction in the speakers' fatigue factor. With the Belden cable the differences between the PS crossover and the original are more pronounced. This is true regardless of whether the speakers are driven by a high power solid state amp or by my 3.5 watt Bottlehead Paramour SET tube amps.

Here's the link to a picture of the latest Art Arrays: http://fredt300b.smugmug.com/gallery/2046580_z6mom#595445502_AA4oG

Thanks, Pete, for offering this crossover design.

djg
07-19-2009, 05:11 PM
Smugmug. Motorcyclist? advrider?

Nice speakers, I like your equipment rack also.

Steve Henry
07-19-2009, 06:05 PM
Fred - from your new photo pages, is it correct that PE is offering a "kit" price for this design, again? I may have misinterpreted.

howard
07-19-2009, 08:59 PM
Fred,
I appreciate what you have done and I hope this will encourage others to try this project. As I have spent more time with them I encountered some of what you heard in the highs. I hope that at some point in the future maybe Pete will stop in Ste. Gen or maybe I can bring them to the city to do some measuring. For my own satisfaction and because all I had to do was swap some banana plugs I am now listening to the speakers using my Rane 2 way and a couple of Dayton APA 150 amps. To me, this sounds the best. I had never heard a line array until this one and I am very happy with what I hear. Maybe I will put something together with better drivers in the future but I like the sound I have now. How much wire would I need to redo the high section as you described?
Howard

Pete Schumacher ®
07-19-2009, 09:08 PM
My pleasure to help out in any way I could.

Wow, those things are BEASTS!!! I'm sure they crank pretty effortlessly.

Glad to hear it worked out for you. At least now, with the higher order XO, you won't have to worry about really turning them up and stressing that tweeter.

Pete Schumacher ®
07-19-2009, 09:09 PM
Fred,
I appreciate what you have done and I hope this will encourage others to try this project. As I have spent more time with them I encountered some of what you heard in the highs. I hope that at some point in the future maybe Pete will stop in Ste. Gen or maybe I can bring them to the city to do some measuring. For my own satisfaction and because all I had to do was swap some banana plugs I am now listening to the speakers using my Rane 2 way and a couple of Dayton APA 150 amps. To me, this sounds the best. I had never heard a line array until this one and I am very happy with what I hear. Maybe I will put something together with better drivers in the future but I like the sound I have now. How much wire would I need to redo the high section as you described?
Howard

Next time I make a trip to St Gen, I'd be glad to stop by.

I don't know how you can do much better than active XOs.

Angaria
07-19-2009, 09:22 PM
How do you deal with the final combined wiring on your arrays as it seems you end up large combined wire thickness? Terminal strips or... ? Thanks.

FredT
07-20-2009, 05:55 AM
Fred - from your new photo pages, is it correct that PE is offering a "kit" price for this design, again? I may have misinterpreted.

Sorry, a few years ago they were offering the "kit" with all the parts at a very attracitve price. I haven't discussed it with them since, but I'll put together a new parts list using Pete's crossover and check to find out what price they're willing to offer. I will post a message in this thread when I find out.

FredT
07-20-2009, 06:08 AM
How do you deal with the final combined wiring on your arrays as it seems you end up large combined wire thickness? Terminal strips or... ? Thanks.

I strip the insulation off a short length of the 12ga Belden cable and solder the driver leads to that piece. The woofers are wired in two groups of four, so there are only two positive and two negative leads to the woofer crossover. The Belden 5000 cable is comprised of tightly wound strands which will just fit the #095-282 .205" 16-14 female disconnects, which I use to connect the drivers in the woofer array.

I also used PE #260-304 bi-wire terminal strips, so only one 12ga wire goes to each connector on the terminal strip. Instead of bi-wiring I connect the tweeter series resistor between the two positive terminals, enabling me to easily swap out different value resistors until the tweeter level is right for the room and equipment I'm using.

Steve Henry
07-20-2009, 08:33 AM
Sorry, a few years ago they were offering the "kit" with all the parts at a very attracitve price. I haven't discussed it with them since, but I'll put together a new parts list using Pete's crossover and check to find out what price they're willing to offer. I will post a message in this thread when I find out.

Thanks, Fred.

blamus
07-27-2009, 07:11 PM
keeping my eyes on this thread, if a kit with the kind of pricing like last time I'll have to go for it. Maybe they can CNC the cabinets too just like the tritrix and have a recession buster array!

Steve Henry
07-27-2009, 08:38 PM
keeping my eyes on this thread, if a kit with the kind of pricing like last time I'll have to go for it. Maybe they can CNC the cabinets too just like the tritrix and have a recession buster array!

Now that would rock!

howard
07-27-2009, 09:44 PM
If you are in Irving, Texas I would stay in touch with Fred T. It would not surprise me to see him sell the ones he made at a very reasonable price. He has made several line arrays and has a great one that he hangs on to.
Howard

rogoll
07-27-2009, 10:44 PM
What is the impedence presented to the amp?

Steve Henry
07-27-2009, 11:49 PM
What is the impedence presented to the amp?

The write-up says 8 ohms, 94 db sensitivity.