Klipsch THX Ultra2 Build Quality

The Ultra2 arrived as a pretty impressive pile of boxes, comprising 10 shipping cartons. Packed inside the cartons were three KL-650-THX (LCR), two KL-525-THX, (back surrounds) two KS-525-THX (side surround) speakers, two KW-120-THX subwoofers and one KA-1000 power amp.

Figure 1: KL-650 THX without and with grill cover

Figure 2: KL-525 back surround and KS-525 side surround, grille covers off.

Figure 3: KW-120 subwoofer and KA-1000 2-channel subwoofer amplifier

Each item was shipped housed in its own carton, well-braced internally with Styrofoam and wrapped in a protective cover.  In Figures 5a - e we see the unpack sequence for one of the KW-120 subwoofers, illustrating Klipsch’s approach to product packaging.

Figures 5a - e: Klipsch KW-120 Product Pack

Note top & bottom Styrofoam inserts stabilizing the KW-120 within the carton, cardboard edge bracing, the essential plastic & foam wrap around the unit itself and the inclusion of the Speakon connector-tipped speaker cable. (More on the included cable later).                                                                                              

Once out of their cartons you’re no doubt going to be impressed by the appearance of these loudspeakers. With or without grille cloth they look great!  Industrial art would be an apt description. Surprised to read of a plain box cabinet being referred to as “art”? It’s the finish that makes all the difference in this case. The appearance of the Galaxy Black finish featured in the Klipsch THX Ultra2 system cannot be captured in a photo that does justice to its striking beauty. Both aesthetically pleasing and functional, the choice of this particular finish with this system was brilliant. How so?

Aesthetically speaking, the Galaxy Black finish has a subtle way of lessening the visual impact of having 9 speakers clustered together in a home theatre. The finish is somewhat lighter than straight piano or charcoal black, not uncommon colors in the world of loudspeakers. Less stark than either piano or charcoal black, the finish is nevertheless dark enough to ensure the speakers present minimal visual distraction.

Inside Look

For the inside look we’ll use one of the KW-120 subs as the specimen of interest.

Peeling off the grill cloth, the sub appears pretty much as seen in Figure 3 above. The four studs to which the grill cloth is attached are actually the heads of the 4 bolts holding the aluminum fascia in place.  Removing the fascia we can then remove the driver.

I laid the KW-120 on its back and proceeded to remove the bolts securing the driver in place. Once I had removed them all, I found the driver at first wouldn’t budge. It seemed like the thing was stuck in place. As it turns out, it wasn’t stuck at all. In actuality I had encountered a driver that was far, far heavier than I had anticipated. I haven’t weighed the driver and cabinet separately, but it wouldn’t surprise me at all if the driver turned out to weigh more than the substantial cabinet into which it is normally bolted.

Figure 7a – b: KW-120 Subwoofer Driver

Figures 7a - b are a couple images of the driver extracted from the cabinet, now sitting on top of it. Once out of the cabinet it was easy to see why the unit was so weighty. The motor assembly is an interesting structure with an interesting history. Kerry Geist, an engineer at Klipsch, wrote in response to my question regarding the possibility the motor assembly was originally designed for use in a larger drive:

“Yes, the KW-120 uses essentially the same motor assembly as one of our 15" subwoofer drivers. However, the motor structure was further improved by adding a copper shorting ring to the yoke to reduce the distortion caused by variations in voice coil inductance. The advantage of using an existing motor design was simply a matter of using a design we already had experience with, and felt we didn’t need a huge engineering effort to develop into a 12” high-displacement version.  We already had plenty of engineering hours wrapped up in the original 15” design...we were just using that “developed” platform as a jumping off point to develop the 12” THX version.  The displacement and power handling requirements between the two drivers were very similar...it was an easy choice to make. Other than the shorting ring modification, I’m not aware of any other changes to the motor assembly itself.  The soft parts of the driver (cone, suspension, dust-cap, etc…) and housing were different of course.  As far as I can remember, the voice coil design is different, but they’re both based around a 3” diameter / 2” coil length format.”

Looking inside the now driverless cabinet, we get a great view of the interior. (Though not evident in any of the photos, the faceplate is double-thickness). There are a number of interesting features.

Figure 8a - b: Klipsch KW-120 Cabinet Interior

The cabinet is cross braced. The brace itself spans the top, bottom and side panels. It also serves to secure the substantial motor structure of the driver. The brace, along with the cabinets various panels, are reinforced with glue blocks placed throughout.

In the background of Figure 8a - b can be seen the interior end of the cabinets duct. The exterior end of the duct can be seen at the top of cabinet’s faceplate in Figure 3. The duct is in fact a collection of panels built into the interior of the cabinet, running parallel to the top and back panels. The interior end of the duct opens at a point just above the Neutrik input jack position on the back panel. The duct also serves as a useful handhold, which comes in handy when its time to move the cabinets around. The cabinets were not stuffed.