3 way sealed high spl studio monitor

Large format studio monitors cost unreasonably much. A decent pair of nearfields can be had at about $800 a pair. Large format monitors start at about $12000 a pair.

I'm hoping to build a high SPL, large format, sealed 3 way monitor. Fundamental flaws were spotted in my last idea, this is another attempt.

I would have liked to build something with a 3" midrange like the ATC SCM 150, but in this case, I'm going for something robust, simple and relatively cheap - I'm willing to live with the attendant compromises.

So my current idea is to have a SEAS T35C002 in a Jantzen waveguide with a Beyma 8CMV2 midrange and a couple of 15" subwoofers intended for sealed cabinets. By keeping everything sealed, it can be
built without complications, and that is a priority for me. Crossover will probably be @ ~100 Hz and ~ 2.2 KHz...

Class D amplifiers and a MiniDSP or similar will handle crossover and amplification duties. I reckon I can build something like this at under $4000 a pair... and there is nothing I can buy at this price point which will accomplish what I'm going for.

Appreciate any and all inputs.
 

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A crossover point of 2.2kHz for a 8" is on the edge, especially for that Beyma unit with breakup starting at 2.5kHz. For a little more money you can buy much better high output midwoofers nowadays, check Faitalpro or 18sound drivers.
But this is just my opinion.
 
Hi Audiothings,
Nice to see you back.
Ok one point: you plan to use 2x15". From my experience you may run into trouble about the box moving/walking at high spl level.
One convenient way to counteract that could be to use them on the side of enclosure ( push-push) and make strong physical connection between their magnet inside the box: the vibration will cancel each others, which will in turn make the cabinet much quieter from a vibrational point of view.
If you still want to put them in wall obviously this won't work... but you could slot load them.
It could give you possibility to try push- pull configuration too if you wan't.
Check for PPSL ( or SLPP some vey good info from member DJK -RIP) on subwoofer subsection to have an idea.
 
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I would use one 15" sub, namely peerless stw 350f, two 16ohm 18 sound 6.5' 6nd430 and a tweeter to match. As in monitors use separate amp for each range (3 way) and 4th order Bessel active crossovers.

cheers,
 
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Consider 6" drivers as well. This driver measures very well and has been used in high-end diy projects and prosound applications.
Eighteen Sound - Professional loudspeakers

This Peerless tweeter looks hard to beat for the money. The metal grill can be easily removed for better performance. Looks like it would possibly work on that waveguide.
Peerless DA32TX00-08 1-1/4" Corundum Dome Tweeter

I would move the crossover up to at least 200hz to keep excursion down. An MTM looks like an option since that tweeter can handle a 1.5khz crossover.
 
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Hi, about subs, as Audiothings already talked about previous idea he needs serious SPL level for professional application.
Target is 115dbspl at 1meter more or less and with closed box.
2x15" Dayton could offer that. 😉
 
My bad, found the previous thread : target is 110db spl.
My brain may have integrated the inwall gain in low end... that said headroom is a desirable feature in that case, always better to have it: this way it doesn't crush transients which will happen in the sub/low way.
 
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How about...

Yorkville Unity U15? Yes it's a PA speaker. In my case, I bought a used pair, crossovers didn't work. But that was ok, because I wanted to run them active EQ, I gutted them, put in some fiberglass batting, made them sealed and use them as home hi-fi speakers. If by "studio monitor" you mean something that you sit a few feet from, perhaps not these speakers. But for $2000-ish (US, double for you?) + some wiring and EQ-ing, you get a pretty good speaker.