Thanks for the fine words. I'll try to live up to them.

On the DIY front I will attend the Dayton (Parts Express sponsored) DIY speaker event on October 23rd in Springboro, Ohio and likely the Atlanta area DIY event (date not established as far as I know but this fall). I'll likely bring the Linus 2 array to Dayton and the Needles array to Atlanta. In Dayton I will give a workshop on line array design. For what it is worth Rick Craig of Selah Audio will be in Des Moines for the Iowa DIY speaker event (October 23rd) and will show off his Omegarray design (built by Jim Holtz) on the 22rd.

I can not help you on the EROS design. I haven't built the EROS. Perhaps you confuse me with Jim Gutterman (Jim G on the Parts Express forum).

I'm thinking of an open baffle line array but I haven't pulled the trigger yet. Dipole speakers have both their pluses and minuses so I'm still weighing what I can accomplish that would be different and better than past work.

Let us hear about your projects as you progress.

Jim

I just finished the baffles on my PE 69 cent mid and PT2 array. I went ahead and bought 16 of the PT2's - figured I'd take your advice:-) It's open baffle but it'll be so close to a wall, I don't expect much dipole effect.

Here's a pic:

I know the baffle looks a little odd but the array will be sitting right next to some very large bass boxes and the effective baffle will be another two feet to the side of the mids. Don't know how the extreme width of baffle will affect it but it won't hurt in getting the most outta the lows. I'll start wiring tomorrow and hopefully get to fire them up before the day's out. Thanks for all your help.

Allan

Very nice looking speaker.
http://www.tolvan.com/edge/ Will help predict the ob cutoff. I think it is about 344m/s /( baffle width-meters). 3' is about 340 hz.

How will you do the x-over? Are the PT2s open back? Will you use a notch filter for the pt2 driver?

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Linc

I just went with a width that fit into the space I have available. I never even bothered to calculate the LF cutoff because I'll get what I'll get anyway - I just made them as wide as possible:-)

"How will you do the x-over? Are the PT2s open back? Will you use a notch filter for the pt2 driver?"

I'm actively crossing them (3-way) triamped using an Outlaw 7.1 amp and an Ashly XR2001 XO. The whole affair is open back and the PT2's are sealead anyway. They're monopole so open baffle or sealed won't make any difference.

I don't plan on any notch filters or BSC at this point. If anything, I'd consider a notch filter for the mid drivers. They have a nasty peak between 7-10Khz, but I'll probably end up leaving the XO point somewhere between 3-5khz. More than likely (hopefully) it'll be a non-issue.

Thanks the photo of your project. I'm sure that you will enjoy your arrays. If you have to place them close to a wall, you might try to attenuate the backwave a bit (batts of fiberglas or layers of acoustic foam located behind the baffle are two ways) if you hear any sound blurring. Generally, dipoles want to have 3-4' spacing from the wall to excel. Let us hear about your results.

Jim

Photos of both at http://fredt300b.smugmug.com/gallery/132721/1/4831163

With a good sub the power handling capacity is enormous, and its 95 dB efficiency will let it play very loud with as little as 10 watts driving it. I use a Consonance Ella amp in triode mode, which clips at about 25 watts, and have never felt the need for more power. I did try a 110 watt/ch Sonic Frontiers Power 2 amp but liked the Ella more. Building a Linus 2 with a good diy sub will set you back about $1,400.

Another line array you might want to consider if you can swing another $600 is the GR Research Alpha LS. For very loud music I would choose the Alpha over the Linus. The Alpha does not need a sub, has even more power handling capacity than the Linus, and can play as loud as 130+ dB; approaching the ear-damaging levels I once heard at an AD/DC concert (in my younger days). The Alpha LS parts kit is $2,000. The enclosure is double walled 3/4" mdf, so building it is more work than the single walled Linus, and each enclosure weighs about twice as much, but it's as inert as as a lead coffin. I only heard the Alpha once driven by a high quality 30 watt solid state amp, but as I recall it will play quite a bit louder than the Linus without sounding strained. You can read about the Alpha LS on the Audio Circle GR Research forum.

Either of these two will play louder than the Eros, but to my ears neither offers the "high end" delicacy.