60 Degree DIY Mid Hi

May 8, 2011
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Sheldon, I would love to build a trap version that could be arrayed, but the complexity with all the angles would make it almost impossible to build as a DIY project.

You also have to remember the design concept was Max SPL and sound quality on a stick (which you noted). When you have multiple boxes in an array they are not stick mountable and your design would use different compromises.

A 60 trap version that could be arrayed in pairs would be great. It could be used as a single 60 degree or in pairs to cover 100 - 120 degrees and looks much better that the current configuration.
 
Feb 20, 2013
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Richmond, VA
To add on to what Peter said about the trap version - it's not impossible. I looked into building them, and somewhere deep in my archives there's a 3D cad version of the box that has 15 degree angles on either side of the box for 30 degree splay between them. There are several considerations in building it, however:
  1. The difficulty in cutting the baffles is extremely high. It requires either extensive table saw jig work or a large radial arm saw to do by hand, and custom ground (or changable) chamfer bits to CNC route. While this is clearly possible, as these kinds of baffles are used extensively in designs by companies such as d&b, Meyer, L'acoustics, JBL, and others, on a small scale it is pretty much unjustifiable to have the entire cabinet be a complete pain in the butt to build.
  2. The front of the cabinet becomes significantly larger to preserve a minimum internal width of 12" at the rear of the cabinet for where the 12" drivers fire into the horn.
    (If I recall correctly, it would have been nearly 600mm at the front, as compared to the current... 450? I don't remember.)
  3. The horn geometry for the bent horn would likely have to be changed, resulting in extensive prototyping issues.
  4. Ain't nobody got time for that.
If these were being made en-masse as a commercial product, this would be more of a possibility. For a DIY project, though, this is just too hard.
 
Feb 24, 2015
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I've had a read through the thread, but can't seem to find it. Sooo.....

What EQ settings are people using for the BMS 4594HE / XT1464?

Using a Powersoft X8 if that helps, so maybe FIR filters might be a shout as well....

Thanks!
Huw, I had not responded because my EQ's are FIR files, and are no doubt too large to fit into the X8's available tap count.
But I got to thinking...if you are using either rephase or FirDesigner, I could send the project file and you could resize accordingly.

Let me know if that would help....
Oh, if so, are you bi-amping or using the BMS passive xover?
 
Jan 15, 2011
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Here is my PM60 doing outfill duty. They worked very very well.
Very nice set up David, how did they perform in this role for you?
Hi Don,

The setup this particular night was for the comedian Gabriel Iglesias. For some unknown reason he has a huge draw in this area. Last year the count was over 12,000 (the marketing folks say 17,000 but that's a stretch) with over 2,000 turned away. This year, for the whole week of shows prior, we had been using JBL STX835 for some side fills. While those are good boxes, the PM60s had far more clarity over distance, which is why I wanted to give them a shot on the last night. There were powered 3 way with itech 4x3500s on each, with the linear phase FIR crossovers. The clarity at 200ft was unreal, especially when compared to the vertec.


Here is a photo from earlier in the week with the STX on outfill duty. This was the largest crowd besides fluffy, but you can get a good view of the space. For the comedian the stage line was stripped down to just the trailer and the decks the PM60s were on. As for the crowd, any and all flat ground (this side of the barricade) was densely filled with people.


 
Likes: Don J Davis
Huw, I had not responded because my EQ's are FIR files, and are no doubt too large to fit into the X8's available tap count.
But I got to thinking...if you are using either rephase or FirDesigner, I could send the project file and you could resize accordingly.

Let me know if that would help....
Oh, if so, are you bi-amping or using the BMS passive xover?
Hi Mark

bi-amping the BMS drivers :)
 

ivan cuic

New member
Oct 16, 2018
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Netherlands
hello,

I'm looking forward to build my first PM90. Was just wondering, I saw a tip if you wanna use CNC to build a box, is it better to use DXF file rather than PDF file. Any thoughts on this?
 
Feb 20, 2013
1,086
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Richmond, VA
hello,

I'm looking forward to build my first PM90. Was just wondering, I saw a tip if you wanna use CNC to build a box, is it better to use DXF file rather than PDF file. Any thoughts on this?
Hi. The reason for this is that the .dxf files are accurate and do not require anywhere near as much work to use to program CAM software. The PDF drawings would require an export, or manual measurement that may alter the final product and cause misfit pieces. Also it's just more time and effort you don't need to be spending. The .dxf files were posted along with the drawings.
 

ivan cuic

New member
Oct 16, 2018
4
1
3
24
Netherlands
Hi. The reason for this is that the .dxf files are accurate and do not require anywhere near as much work to use to program CAM software. The PDF drawings would require an export, or manual measurement that may alter the final product and cause misfit pieces. Also it's just more time and effort you don't need to be spending. The .dxf files were posted along with the drawings.
thanks Max, makes sense!

I've just spent my afternoon reading the whole thread again and I found final version of a plan, but I didn't found .dxf file. Would you mind sharing it with me? Cheers Ivan
 
Oct 15, 2018
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Dominica
Unfortunately I can't take the credit for building these, they were built by a local cab builder, but...

The boxes are removable to make it easier to fit the 12's. The handles are placed for a 2 man lift, probably not really needed but there's always a few of us setting up, these ones are also slightly wider and made out of 18mm so are heavier than the original. And yeah we will be laying them on their backs when transporting/storing.

Here are a few more pics of the build process...
How much will it cost to build 6 of these and ship it to Miami?
 
Feb 20, 2013
1,086
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Richmond, VA
thanks Max, makes sense!

I've just spent my afternoon reading the whole thread again and I found final version of a plan, but I didn't found .dxf file. Would you mind sharing it with me? Cheers Ivan
So technically I lied - I posted a .dwg file, which is a less standard sort of interchange file than a .dxf. It's fundamentally the same, though. Let me know if you really need me to export a .dxf instead of the .dwg.

And, many months later...

These are the dropbox links for the current .dwg and .pdf files. I will always keep these public facing ones as updated as possible if I make changes in the future, so check revision numbers and publication dates if you're wondering about a newer version.
https://www.dropbox.com/s/h16is6mbjig6fcy/pm90_current.pdf?dl=0
https://www.dropbox.com/s/xiuyecjy9k6weph/pm90_current.dwg?dl=0

This has been quite a journey, from not knowing a darn thing about building cabinets to having these plans in a somewhat presentable format. Next project: something simpler!
 
May 8, 2011
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Australia
Hi David,

Love your pictures of the PM60 next to the 4888's ... fantastic.

FWIW you can get resonably good results if you have about 5 bands of PEQ per band on an IIR crossover, but you will not quite get the magic you can get with FIR filtering.

Peter