Product Review

Product Review

Spatially Challenged

It’s hard to tell the story of these speakers without also telling a little one of my own.

Like so many others, my home theater was for many years part and parcel incorporated into the living room. My wife and I get along just fine, and we compromised well: She put up with those big ugly boxes (a.k.a. speakers), and I put up with country style wall paper. There were times though when I wanted to get away to a movie-only zone without being preoccupied with whether I’m disturbing anyone, or, more importantly, if anyone is disturbing me. Beyond that, I’m supposed to be an Associate Editor for a recognized web-zine. I of all people should have a dedicated room. right?

Trouble was, we had no space, at least none that loaned itself to a home theater. There was plenty of real estate in the basement but none of it contiguous: A load bearing wall through the middle precluded the creation of a normal sized theater.

In a fit of courage (or perhaps madness), I conceived a two-seater theater in an unfinished 10×11 space. The acoustically knowledgeable among you will already be making assumptions about the sound (as I did), but casual consultation with acquaintances, including one at THX, assured me it could work. A substantial opening at rear right, lots of absorption and diffusion in the right places, a notch filter on the subwoofer, and indeed the room sounds way better than our living room ever did. When it’s 100% done, I’ll do an article on how it all came together.

I did get one warning though: The rear surrounds are going to be tricky .

The only way a pair of monopoles could be placed such that they did not shout, Hey, over here! was to place them on the floor, pointed at the ceiling. Not a bad surround sound field but not a practical solution (the cat kept wanting to park himself on one or the other during a movie). I’ve always advocated dipole surrounds, but the textbook correct placement would put the right surround speaker somewhere in mid-air, precisely where we walk in. Then a press release came across my virtual desk: In-Ceiling Di-Pole speakers from Atlantic Technology.

Since you almost never see reviews of in-wall speakers for obvious reasons, I decided to offer up my ceiling to you our readers and give these a try.

Location of the IWST-8 speakers under review in The 007 Theater

The IWTS-8

The IWTS-8 is the larger of two models specifically designed for ceiling installations. Its 4-1/2 depth requirement actually makes in-wall installation in normal 2×4 construction impossible without some serious fudging.

When fellow Secrets staff member Sandy Bird came over to check them out, his first reaction was, Oh, you’ve used car speakers. He was half serious I think. While I’m told a pair of coaxially mounted tweeters over a woofer is a common configuration in the car audio world, the IWTS-8 has nothing in common with a car speaker. They are made entirely in the USA to Atlantic Technology’s spec and are not an adaptation of an existing design or product.

The IWTS-8, through a set of jumpers and switches, can be configured to operate in one of three modes:

Tri-Vector. The two tweeters are out of phase with each other (the two domes move in the opposite direction at the same time). Note that this is mode is not called dipole since it only operates as such above 2kHz.

Monopole. The two tweeters are in phase with each other (the two domes move in the same direction at the same time).

Stereo. The two tweeters get their own input, as do the separate voice coils in the woofer. Basically, think of it as two conventional speakers right next to each other. Reminds me of the prescribed arrangement for the rear speakers in a THX Ultra2 set-up. We’ll talk about that later too.

Crossover board and input terminals

There is also a treble adjustment switch on the tweeter baffle with three settings: flat, reduced, and boosted. The intention is to compensate for how far off-axis you are (the further off, the less treble you get). It is a very mild adjustment, 2 dB either way, which Atlantic Technology feels is appropriate for the purpose.

We elected to try a pair, configured as TriVector, to the left and right of the seating area, placing them as far apart as possible, equidistant to the seats, without the right surround channel being out of the room. Our seating arrangement puts our heads right in line with one of the ceiling’s main runners, so we plotted the surrounds’ placement just back of that line.

At 8 pounds+, these speakers are not exactly feather weight, and as such I did not feel comfortable asking the acoustical ceiling tiles to hold all that mass. Our solution was to make mounts out of 1/2 MDF board, cut to a length of 23-3/4 (the width of a ceiling tile), thereby spanning the distance between two main runners and thus putting all the weight on the grid. Using the supplied template, I traced the 9-1/2 circle onto the MDF, making sure it would place the speaker right where we wanted it, and cut the hole with a jigsaw.

I placed the board on top of the ceiling tile, being careful to position it where I wanted the speaker, and then used a utility knife to cut the tile, letting the MDF’s hole be my guide.


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