Soffit mounted WMTW surrounds

[Paul W]

I need to upgrade my rear channel and surround speakers and have been pondering the WMTW config. (12" max height limit)

Location is the trickey part...the underside junction of the wall and plant ledges running along the side walls (the plant ledges look like an 8' ceiling near the speakers). So, a sloppy waveguide I don't know how to model. The side/rears would point directly at the listening position, the rear/surrounds bounce off the back wall for a diffuse effect.

Here's the concept so far. SS 18W8531 woofers in a sealed box (overkill, but I have them in a closet), Seas MCA15RCY mid, 27TDFC tweeter (don't have these yet). Woofer-mid xo would be 1st order series fed by a 2k low-pass. Mid-tweet would be mounted on an "invertable" sub-baffle so that, in real life, location can be reversed and I can experiment with xo order to get the best overall response from my unintended waveguide.

I'm not trying to "nail" a design yet...just exploring concepts at this point. Any other configurations I should add to the mixing pot this weekend?

[cjd]

This sounds very similar to one of the things I've been pondering - think we already established this fact though.

Pics would be useful here I think. Soon as I get things rolling again (was out of town for a few days) I'll see about tossing some of my thoughts into images.

And, aside from any visual demands, is there a reason you're going with the Seas drivers? Or just 'cause you wanna?

I know I will not be going Seas in my HT - just can't justify the cost. RS stuff would match Seas well enough in surround duty and we might manage a two-for-one that way. :P

Regardless, should be fun to see what develops.

C

[Paul W]

I used the same Seas drivers in a project for a friend this summer and came away very impressed with performance for the moderate cost. Also want to build something good enough that I won't be tempted to replace...rather play with crossovers than woodworking.

The sims this weekend looked great for the "low and slow" woof-mid crossover (though I did switch to parallel 1st order). The mid drops away quicker than 1st order below crossover, but it seems to work okay. Excursion also okay with the large mid.

Still no real clue about the reflections off nearby surfaces. Grill cloth is needed, so toying with the idea of 3-4 layers of 1/4" felt on the baffle...layers cut and shaped to minimize launch to the surface above.

[cjd]

The tweeter, I'll agree is a top choice. The other two drivers (re-reading I note that it's one SS), well - absolutely good stuff.

I'll be doing the 27TDFC, just probably will go with RS125 mid and very likely RS180 (a pair perhaps) for woofer. Different approach in the end I think.

C

[Paul W]

Stay in touch...I'd really like to see how yours evolve. The environment we're putting these in may ultimately play a larger role than our choice of drivers!