IWTS-155 LCR THX Ultra2  

Top THX-certified performance, between 2 x 4" studs!

sm_IWTS-155_LCR_front.jpg“The IWTS-155 LCR solves the dilemma of getting the best sound possible when you have to retro-fit between 16"-on-center studs. A perfect solution!—Peter Tribeman, President, Atlantic Technology

THX  Ultra2 Performance that fits everywhere!
The IWTS-155 LCR  is a premium-performance in-wall speaker that addresses the need for no-compromise performance with the flexibility to mount either horizontally or vertically in standard 16"-on-center stud-framed walls.It is a perfect solution for retro-fit applications and its small footprint makes it particularly inconspicuous when installed.

The 155's MDF baffle continues Atlantic's use of non-resonant baffle material for in-wall speakers, resulting in far better acoustic performance than speakers that use 'ringy' plastic or resonance-prone aluminum baffles or enclosures.

As a final touch, the 155 has two easily-accessible controls on the front panel (Boundary Compensation and HF Level) to adjust for varying placement and room acoustics situations.

The required GFR-155 grille/frame assembly is packaged and sold separately, so the grilles can be installed and painted during the construction phase, and the speakers themselves can be installed later on.

Rated for Medium to Large Rooms
View Room Size Ratings



Surround Options for IWTS-155 LCREXCITElogo-final-09.JPG
IC 8.3/6.3e
IWTS-14/30 SR

Feature List

  • Sonic performance is a perfect match with our other Atlantic THX in-walls
  • Easy horizontal mounting between standard 16"-on-center, 3 1/2"-deep wall construction
  • Backbox (IN-BOX-155) sold separately, required for THX-certified performance
  • Boundary Compensation and High Frequency sound-optimization controls
  • The GFR-155 grille/frame assembly (required) is packaged and sold separately for maximum installation/scheduling flexibility
ico_pdf.gif Manuals
ico_pdf.gif Brochures
ico_pdf.gif Installation
ico_wm.gif Video

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Model IWTS-155 LCR
Drivers Dual 5 1/4" (135mm) GLH* long throw woofers w/Butyl rubber surrounds and high power motors
1' (25mm) Low Resonance Tweeter w/Neodymium magnet and Ferrofluid cooling
Configuration 2-way

High Frequency Level
Boundary (Near wall/corner or mid-wall)

Frequency Response 58Hz - 20kHz +/-3dB
Sensitivity 89dB, 1 watt, 1 meter
Impedance 6 Ohms
Crossover frequencies 2100Hz
Recommended amplifier power 10 - 150 Watts RMS
Optimum wall volume .5 cu.ft.
Overall Dimensions (W x H x D) 15 1/2x 8 1/2 x 3 3/4" (395 x 216 x 97mm)
Cutout dimensions (W x H) 14 1/4 x 7 1/8" (362 x 181mm)
New Construction Bracket (optional) IN-NC-155 (use only if IN-BOX-155 is not being used)
Back Box (optional, but req'd for THX certification) IN-BOX 155 LCR for new construction
Weight 8 lbs. (3.6kg)
* GLH: Graphite-Loaded Homopolymer
Atlantic Technology reserves the right to change specifications or appearance at any time without notice.


The IWTS-155 LCR is the perfect answer to the seemingly contradictory demands of no-compromise performance and the ability to fit horizontally between standard 16"-on-center studs. This system represents a combination of superlative audio performance, simple installation, and innovative features that are unmatched by virtually any other custom-installed system.thm_IWTS-155_LCR_rear.jpg

This THX-certified (pending) front-channel speaker forms the heart of a top-performance home theater system. It is a 2-way system with a two long-excursion 5 1/4” woofers, and the very latest version of Atlantic’s exclusive 1” Low Resonance Tweeter (LRT™).

Use the 155 as a center channel speaker with either of Atlantic's other THX-certified in-wall speakers, the IWCB-727 or the IWTS-30 LCR. Because of its ability to fit horizontally between standard stud spacing, the 155 makes a perfect center channel match for these speakers, with absolutely no drop-off in performance or output.

Alternately, you can use three 155's across the front LCR stage--either vertically, horizontally, or a V-H-V combination--for a virtually perfectly, seamless front theater sound.

Front Panel Controls:thm_IWTS-155_LCR_front.jpg

- HF level—Adjusts tweeter’s output for varying room acoustics

- Boundary—Adjusts upper-bass/lower-mid response to correct for “boundary gain” when speaker is too close to corner

The optional IN-BOX-155 back box provides the proper enclosure volume for optimum THX-certified woofer response, and minimizes acoustic bleed-through from one room to another.

Separate GFR-155 grille/frame—Grille/frame assembly is sold separately from speaker portion, to maximize installation scheduling convenience.

This speaker’s THX certification is your assurance that the IWTS-155 LCR belongs in the very highest category of precision, high-performance audio devices.