JTR Speakers

Less a question of serious versus casual than of how much room you are willing to give up. Kallos is the shallow line — 4.25 inches deep on the wall, or fully recessed with the 38IW — and it is a genuine performer: the 465 is 97 dB sensitive and rated at 123 dB usable output, which is more than a small or medium dedicated room will ever ask of it. Mounted flat to the front wall it also hands back the floor a tower would have taken, and in a small theater that is often the binding constraint.

Noesis goes further, and it goes lower. The 212HTR is rated 134 dB usable, and the 215RT plays to 18 Hz — in cabinets that are furniture-scale, the 215RT standing 70 inches tall and shipping at 236 pounds. That headroom earns its keep in a large dedicated room run at reference level. It earns much less in a small one where the seats are ten feet from the speakers.

So: a large dedicated room, or one where you want reference level without leaning on subwoofers, points to Noesis. A smaller dedicated room, a media room, or any space where the speakers cannot project into the floor points to Kallos — and not as a consolation.

The reputation comes from older horn designs, and it is not what a modern compression driver on a properly shaped waveguide does. The point of the horn is controlled directivity — the speaker sends its output at the seats in a defined pattern (60 x 60 across most of the Noesis line, 70 x 70 on the 215 models, 90 x 60 on the Kallos) instead of spraying it at the side walls. Less reflected sound arriving late is usually heard as more clarity, not less.

It is a different presentation, though, and worth being honest about: controlled directivity means aiming matters. A JTR pointed at the back wall rather than the seats will not sound the way it should, which is a large part of what installation is for.

The Kallos line can, comfortably. On-wall at 4.25 inches deep is shallower than most people expect, the 38IW disappears into the wall entirely, and the 12Sub is front-firing throughout so it can sit tight against a wall or inside cabinetry without choking.

The Noesis line is a harder sell outside a dedicated room, and we would rather say so than talk you into it. Matte black cabinets with large visible horns are not discreet, and the 212 and 215 models are big. If the speakers have to recede visually, start with Kallos.

Both use an 18-inch driver and a 2400-watt amplifier, so the driver and power are not the variable. The RS1 is sealed and measures 21 inches wide, 18 deep and 21 tall, rated to 22 Hz outdoors with room gain taking it lower. The 2400 is ported, rated to 12 Hz, and considerably larger at 20 wide, 22.5 deep and 30 tall.

The ported cabinet gives you more output in the bottom octave, which is where the very lowest film effects live. The sealed cabinet is smaller, easier to place, and in a typical room the difference is smaller than the specifications suggest once room gain is included. If the room is large or the goal is the bottom octave at volume, the ported models earn their size; otherwise the RS1 is usually the easier decision to live with.

Not in these four — though the question is a fair one, because normally cabinet shape and volume would matter a great deal.

What sets a subwoofer's sound is its net internal volume and its tuning, and these four share both, along with the same pair of 18-inch drivers, the same 4000-watt DSP amplifier and the same published response of 10.5–125 Hz. The external dimensions are a rearrangement rather than a redesign: in inches, width by depth by height, the 4000ULF is 20.5 x 39.5 x 41 and the LP is the same three figures reordered at 39.5 x 20.5 x 41, while the TL is 20.5 x 28 x 58 against the ST at 58 x 20.5 x 28. Work the volumes out and all four land within a third of a percent of each other, about 19 cubic feet in every case.

The things a cabinet's shape does change — internal standing waves, baffle diffraction — occur at wavelengths far shorter than a subwoofer is ever asked to reproduce. At 125 Hz a wavelength is about nine feet; at 20 Hz it is over fifty. The box is acoustically small at those frequencies whichever way up it stands.

Where the shape genuinely does change what you hear is where it lets you put the subwoofer — and that effect is far larger than anything happening inside the cabinet. An LP tucked under a riser, a TL standing in a corner and an ST lying behind the seats will measure very differently in the same room, because below 125 Hz the room dominates. So it is a placement decision rather than a performance one, with the caveat that placement is among the most consequential acoustic decisions in the whole system — which is why it is worth modeling with the Subwoofer Placement Calculator rather than guessing.

More than one, in almost every room. A single subwoofer can reach reference level easily — a Captivator 4000ULF will not run out of output in a domestic room — but output is not the problem multiple subwoofers solve. Room modes make bass loud at one seat and thin at the next, and no amount of power from a single location fixes that. Two subwoofers placed well usually cut seat-to-seat variation dramatically; four gets closer still.

You can model this before buying anything with our Subwoofer Placement Calculator, which shows how sub and seating positions interact and compares bass consistency across the seats.

They are passive, so the power has to come from somewhere, and the general recommendation is a dedicated amplifier rather than a receiver. Most of the line is 4 ohms, and a receiver's advertised power is measured into 8 ohms with only two channels driven — with every channel working there is far less available per channel than the number on the box suggests.

The exceptions are real, though. Surround and height speakers sit close to the seats, and halving the distance quarters the power needed, so a receiver drives those comfortably — the 110 family included. The 212HTR and 212RT are efficient enough to be easy anywhere in the room. And any of these speakers will play normal listening levels on a receiver quite happily; it is reference level in a larger room, on the less sensitive models, where an amplifier stops being optional.

Yes. Room correction runs in the receiver or processor, not in the subwoofer, so any Captivator works with Dirac Live exactly as any other subwoofer would. The subwoofer's own DSP handles its response; Dirac handles the room.

One thing to plan for early: Dirac Live Active Room Treatment addresses each subwoofer independently, so it needs four independent subwoofer outputs on the processor. Not every receiver has them, and it is much cheaper to choose the processor with that in mind than to discover the limit after the subwoofers are in the room.