RBH TK-5CT Build Quality

You’ve read a lot of RBH reviews over here and if you’re anything like me, you’ve thought, “Well, that’s nice, and if I ever hit the lottery, I’ll look into those.” At CES this year, we were sitting in the RBH room listening to the T-30LSE speakers (the very same ones Gene has) and I kept staring at the TK-5CT’s thinking, “Why aren’t we auditioning those?” We’d all already heard the T-30’s, and these newest RBH’s are actually within financial reach of a lot of our readers. As we stood up, I mentioned to Gene that I thought we should do a review and bada bing, bada boom, here we are.

Build Quality

The RBH TK-5CT’s come in three boxes – one for each speaker and one for the two bases. The high gloss black tops and bases were covered with a film of plastic to keep them in pristine condition during shipping. The towers are thinner than any of the towers I’ve reviewed and the bases are quite large which makes them the steadiest towers to date. The plinth (I love using that word) has a matte finished wood block that holds the main speaker away from the piano gloss base.

The TK-5CTs have a soft dome tweeter, two 5 ¾” midrange drivers, and an 8” side firing woofer. The woofer section has a rear port to increase the amount of usable bass the speaker can provide. The front grill is probably the sturdiest I’ve ever seen consisting of a 1/2” MDF and chrome posts. The grill came off and on easily and at first I was afraid that it was a little too easy but I never had a problem with them working themselves loose. The side grill is also removable and is constructed of the same quality of materials as the front grills with the exception that it doesn’t have posts. Instead they just sort of wedge in the hole enough so that they stay securely but not so much that they are impossible to take off. It is hard to take them off (this is a good thing in my opinion) but not impossible. The center of the tweeter is 39 ½ inches off the ground. This is a little taller than most of the towers I’ve reviewed including the Axiom m60’s that I use as a reference in my system.

The speakers are caped with a piano gloss black plate that angles up away from the front of the speaker. The remainder of the speaker is wrapped in a rosewood-colored vinyl veneer which is as good as any other vinyl veneer I’ve seen. The vertical edges of the speaker are harsh but the horizontal ones are pleasantly rounded. The high gloss piano black base is secured using four provided screws which mount into metal threaded inserts in the bottom of the speaker. I actually had a pretty hard time with these screws as they didn’t seem deep enough for a Phillips head screwdriver but were so wide that I had a hard time finding a flat head wide enough to tighten them without slipping. Make sure you are careful when installing the base. It is very easy to pull the threaded inserts loose. You’re not trying to torque them on, just get them good and snug and walk away. The top edge of the base is mitered so that the front of the base is slightly thinner in appearance than the back. This follows the angle of the top nicely and is a very interesting aesthetic touch. Near the four corners of the base are brass inserts to accept either a carpet spike or a screw with a rounded rubber head. The spikes actually have a nut adjustment which, while not as aesthetically pleasing as some of the spikes I’ve used, is infinitely easier to adjust. At a maximum useable length of about an inch, you may have to look into aftermarket spikes for your longer pile carpets.

Editor’s Note: One often hears that carpet spikes “tighten up” bass. But why? Well, think of it this way, the driver is moving in and out in order to make noise. If the cabinet is “floating” on the carpet rather than securely anchored to the floor, it is moving too. This can lead to a “muddy” sound that many notice. Coupling the speaker to the ground can help clear this up by increasing accuracy. As always, experiment for yourself and see if it makes a difference in your room.

One glaring omission on the TK-5CT’s is the lack of bi-amping ability. Even though this is an 8ohm speaker, it is relatively insensitive at 87dB (2.83 voltz @ 1 meter). When I first hooked them up, I used the Denon AVR-2307CI. This mid-level receiver has a number of very convenient options including the ability to choose a different setup for stereo versus multi-channel inputs. What does this mean? Well, with the TK-5CT’s, it means I can run them with a sub for movies and multi-channel music and then full range for two channel music – all without hitting a button! While the 2307CI powered the TK-5CT’s adequately, switching over to the Emotiva RSP-1 reference stereo processor and RPA-1 reference stereo amplifier brought a whole new level of audio quality. Most notably, everything was crisper, less muddy, with an overall increased fidelity to the playback. It takes a quality speaker to reveal those differences in electronics and the TK-5CT’s are just such a speaker. Aesthetically, I wasn’t very taken with the TK-5CT’s. They look fine with the grills on but the yellow fiberglass drivers just look wrong surrounded by the red finish. This is one of the few speakers that I prefer the grills on.

Taking the speakers apart I noted that each of the drivers save the 8” woofer was fully shielded, the baskets were all stamped and the enclosure was constructed out of ¾” MDF. The rear port was flared at both sides to reduce port chuffing or noise. The interior is lined with a thin layer of white polyfill that  appears to be mostly used to keep wires from vibrating against the side of the cabinet rather than any real dampening. When I first started exploring the insides, I thought that there was a solid brace across the speaker just below the bottom 5 3/4" woofer. This would make sense as it would isolate the 8” woofer from the other drivers. But when I got behind the tweeter and two 5 3/4" woofers, I realized that they were incased in a box that was only about half as deep as the speaker. A few minutes of investigation later and I found a hole leading up the back of the speaker just above the port. This means that the midranges and tweeter are enclosed in a smaller box but that the unused space behind them is still being used for the woofer (explaining the bass extension I experienced). Now, what is amazing is that I’ve seen this design before from RBH – on their flagship T-30LSE towers! It would have been cheaper and easier to just put a solid cross brace in there and forget about that unused space behind the mid/tweeter box. But that’s not a concession that RBH is willing to make. And I appreciate that.