DIY Lightweight Compact 2-Way PA Speaker

Yea I looked at the recommended enclosures from the major driver manufacturers. Some look attractive but I have some doubts regarding the output for sure.

I think I may have found a way to do this using dual B&C 12NDL88's. They are super light and very efficient. I did a quick sketch up to get started.
Looks like you are struggling to get 2x12 into your form factor. It’s dual-10 territory. But that NDL88 is one hell of a nice driver. A dual 12 that is a bit bigger than what you originally wanted, comes in under 50 pounds and can knock you on your *** is worth something. Then you go and build a nice little 10”/1” that weighs in around 25…. For those times when you’re feeling lazy.

My dual 12 weighs 90 pounds apiece. All ferrite, with a 2” CD of course. It’s a b*tch getting them on the poles.
 
It could work, but the response above 600Hz will be ugly, you would want to use a HF horn that could be crossed lower than the RCF 94.
The Fulcrum Acoustics US212 will give you an idea what the short "V" horn does to the upper response of two relatively flat 12" woofers:
View attachment 1333373
Considering your desire to use a passive crossover, I wouldn't advise using a "V" loading.

Using 2x12" front loaded really requires a 2.5 way crossover (rolling off the lower woofer to avoid comb filter problems in the crossover region) to get decent upper mid sound. That makes for a more complicated crossover.

Using a single 14" B&C 14NDL88 would get you ~125dB while still within Xmax, save about 10 pounds of driver weight over 2x12", and simplify both cabinet construction and the crossover.

Definitely a lot easier than the SynTripP 😉

Art
Thank you for clearing that up. I kinda figured that might be the case and to be honest
 
Looks like you are struggling to get 2x12 into your form factor. It’s dual-10 territory. But that NDL88 is one hell of a nice driver. A dual 12 that is a bit bigger than what you originally wanted, comes in under 50 pounds and can knock you on your *** is worth something. Then you go and build a nice little 10”/1” that weighs in around 25…. For those times when you’re feeling lazy.

My dual 12 weighs 90 pounds apiece. All ferrite, with a 2” CD of course. It’s a b*tch getting them on the poles.
Thanks for the encouragement on the dual 12, and I may still do a slightly larger simple flat baffle dual 12/1.4 to replace my Renkus CT5's which are really meant to be install speakers and are very heavy. They get very little use but it is still nice to have something bigger for the few situations where I need them. The cost would be fairly reasonable. I will say though, those bulky, heavy CT5's sound very nice and throw a long way with minimal power.

For the moment, I intend to build a simple 2-way using the B&C NDL88 and 18Sound ND1460/RCF HF94. I hope to have the prototype cabinet constructed and drivers installed by the end of the month. Still debating the active/passive thing. I would like to keep my amp rack as small as possible so I'm inclined to go through the crossover design learning curve but I'll cross that bridge in a few weeks.
 
And thank you all for your input and guidance. I really do enjoy projects/building things particularly when I feel there is a legitimate benefit to others in the industry. I had seriously considered the SynTrip and there is no doubt in my mind it is a great performer but while I fancy myself a decent woodworker, it is not what I would consider a simple build.
 
A simple single 12/1.4 was what I was originally thinking early on, as it has the same surface area as two 8’s but beats them in all other respects when trying to get down to 80 Hz. At least a premium driver would. And easily comes in at 40 pounds with any neo drivers. There are 2.5” VC drivers all over the place for $200 that might not have any more output than a pair of premium 8’s, but the highest output 12’s have bigger coils, more throw, and of course go for more money. 12NDL88 isn’t the absolute highest output driver out there, but it’s damn close if you don’t need bass bass. They may really be onto something with that 3.5”VC motor - they managed to keep the weight down, where every 4”-er out there is 13+ pounds. Most of them were intended as compact subs, though.
 
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A simple single 12/1.4 was what I was originally thinking early on, as it has the same surface area as two 8’s but beats them in all other respects when trying to get down to 80 Hz. At least a premium driver would. And easily comes in at 40 pounds with any neo drivers.
Yea it takes some of us little longer to come to the right conclusion. 😉 but I guess early on I had it in my head that I wanted a very narrow cabinet.

12NDL88 isn’t the absolute highest output driver out there, but it’s damn close if you don’t need bass bass.
I have no hands on experience with it yet but the specs for the price look pretty dam good. I see 18sound has a12NW350 that is very similar and Beyma has the 12P80NdV2 which looks absolutely incredible but it is also $150 more here in the US. Also Faital12FX600
 
Okay here is what I ended up with. Weight should be right 37Lb using 18mm BB for plywood. I basically ended up using the B&C's recommended box volume and tuning parameters. Cost should be under $1,500. Outer dimensions are pretty much 24.5T x 13.5W x 16.1D.

If I am careful, I can get two cabinets out of one 4x8 sheet of plywood. I am lucky enough to have a local supplier that carries 4x8's. Should be a fun weekend.
 

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Basically, everything needs stiffening ribs. The braces don’t need to be solid all the way across. I’ll ususlly put one in behind the driver - with a half-moon cutout. Can put vertical strips along the side walls between it and the top and bottom. Double-thick the front baffle if you can since stiffening it is harder.
 
So I spent the day the cutting panels. Good so far except the weight. Somehow I manage to underestimate the weight of 18mm BB. I believe the enclosure will end up closer to 30Lbs. Do you all have any opinions on the RCF ND950 vs 18Sound 1460? Or is there another driver high frequency driver I should be looking at? I am looking for a very clean mid range.
 
Well I want very clean mid range from 750Hz up and clean, undistorted at 20K but I think we all know that isn't possible from a single compression driver. The two aforementioned drivers are pretty much equal cost for me as of today.
 
Have you thought about using a coaxial mid/HF compression driver - well within your budget and will crossover at 400Hz. Add a pair of 10s crossed over at 120Hz to your subs and you have a compact lightweight system. 15mm ply is more than adequate if the enclosure is designed correctly with no big flat panels. It's what I'm using on my 21" subs!
 
In general bracing adds more stability than thicker panels. 12mm is getting more complicated to join. So more work and clamping tools is needed to build such a cabinet. 15-18mm can be nailed and screwed by any DIYS capable person. That is just my experience.
The heavier is better thing from HIFI is nothing to make a PA man happy.
 
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