4-way active PA. Techno system! Build thread

m R g S r

Member
2011-01-07 5:59 am
I will make this my build thread for my DIY 4 way active PA.

The anchor of the system will be my designed PAL12 tapped horn subs.
Thread here:
http://www.diyaudio.com/forums/subwoofers/232219-325-lab-12-based-pa-tapped-horn-35hz-extension.html

The system will consist of:

(2) PAL12 subwoofers 30-100hz (Eminence LAB 12)
(2) Double 15" super compact midbass 100-500Hz (celestion 15" ts-be-15300)
(4) 8" sealed back midrange 500-2000ish maybe 2200Hz (Eminence Alpha 8a)
(2) 10" round horn waveguides, 1" compression drivers. 2000hz or 2200hz and up (18 sound ND1070)

Amps:
QSC RMX 4050HD
QSC RMX 1450
QSC RMX 850
Crown D45

Processing:
DBX driverack 260 (4 way mono)

8c 13awg wire for each left and right, will make setup super easy.
All Neutrik Speakon connectors

There are very limited size restrictions (for transport purposes) hence the undersized midbass (and no horns booo!)
 
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m R g S r

Member
2011-01-07 5:59 am
Got one midbass almost complete.
imageehl.jpg

imageqzl.jpg


Might add a little more 18mm bracing
imageivu.jpg


imagezhj.jpg

imagegro.jpg
 

m R g S r

Member
2011-01-07 5:59 am
This is the way I plan to run the cabinets tapped horn turned down on its side for the base, then the midbass standing up
imagevfpi.jpg


Quick pic after I dragged both subs out to test fit in the car....
imagefetz.jpg


Got started on the second midbass as well.
imageefw.jpg
 
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This is the way I plan to run the cabinets tapped horn turned down on its side for the base, then the midbass standing up
I would strongly encourage you to use the sub vertically to get (most) of the mid and high frequencies above head level, or use the sub as a base and put a pole under the mids.

The system below, (also using Lab 12s for LF in a similar size cabinet as the Pal plus waveguides), uses a speaker cord box as a stand to elevate the top cabinets (containing one 10", two 6.5", and two HF drivers) to 67.5 inches high. The cabinets use interlocking dowel pins and ratchet straps to secure the tall system against the crowd and wind.

People can stand only a few feet in front of the system and not hurt their ears, and without the HF being absorbed by them, it carries much further.

The whole system fits in a small trailer, avoiding abusing the interior of my Mustang.
Building the trailer was a lot easier than building any of the cabinets...

Art
 

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4-Way active PA

Nice system break down weltersys! It all fits in that trailer? What about the amps and processors? Curious how the system looks up close be very interesting what you other guy's are building. Any plans for the trailer OR should I look at Popular Mechanics mags? Thanks! I love this site!:)
 

turbodawg

Member
2004-02-13 12:51 am
Hmm thanks art. I'll see what I can come up with.

I would agree with Art. IMHO everything above 200hz or so should be above head height. So, bottom of your mains cab at least 6ft off the ground. Tough to say about your kick/mid bins, typically a kick bin would be around chest/head level but would only be used 80-200hz or less. 400hz coming out of those double 15's at torso to head level is going to be absorbed by the the crowd, not to mention deafening to be in front of.
 

turbodawg

Member
2004-02-13 12:51 am
I'm still thinking this is going to be sub bass shy. The kind of top/kick setup you have would typically be paired with 2x 18" horn subs each side or 2x 2x18 reflex on each side.

My 15" reflex have similar estimated max output to the PAL12 (~125db 1m) and match up well with normal 10" PA tops on 200w.

You may want to seriously consider putting the subs together and corner loading them in most venues.
 
Nice system break down weltersys! It all fits in that trailer? What about the amps and processors? Curious how the system looks up close be very interesting what you other guy's are building. Any plans for the trailer OR should I look at Popular Mechanics mags? Thanks! I love this site!:)
The entire sound system other than a few items which go in the trunk of the tow vehicle fits in the trailer, list below.

No plans for the trailer, it's basically a box on top of a kit trailer bought at a Menard's, a store like Home Depot or Lowe's .
I have seen some trailer kits for cheap at Harbor Freight.
It is overweight, but I had the kit, which had been a land/ice yacht in it's first incarnation about 25 years ago .

Like Turbodawg, I am also curious as to how mRgSr plans to deploy a pair of wide angle waveguides per side.
If horizontal, their dispersion will be about three times as wide at the crossover point as the 15" mids.
If vertical, there will be radical HF comb filtering at various distance from the stack.
Of course, for techno, that might be a good thing ;).

Art
 

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