S55i Subwoofer

Available in In-Wall and In-Floor/Ceiling version.


The S55i Subwoofer
Following in the footsteps of the S90i, the S55i in-wall/in-ceiling subwoofer’s highly efficient and more compact design yields fast, dynamic, articulate results with accurate timbre. Whereas the extremely popular S90i requires a 6-inch deep wall for in-wall installation, the S55i can be placed in a 4-inch deep wall. Its smaller form factor will also provide additional placement flexibility in locations where the S90i is too tall.

We examined all types of transducer and cabinet loading options to determine a design that would complement the extraordinary dynamics and low distortion of our in-wall planar magnetic systems. The Regenerative Transmission Line® topology has proven to be ideal for ensuring a high performance, no-compromise low frequency solution across a range of installation options, but especially when installed in a stud bay, ceiling, or floor.

The S55i can be mounted in-ceiling, in-wall, under risers, in closets, and in floors. It is a rare example of a custom-centric design that offers competitive results versus the finest freestanding options. The S55i is a strong performer, featuring the quickness and tonality all our RTL subwoofers are known for, with bass extension to 35Hz. Its size makes it well suited to being custom-installed and thereby hidden behind its small paintable grill and bezel.

Pair either one or two S55i’s with the SW-1 or miniDSP-1 for an exceptional subwoofer system at an affordable price. The unique solution offered by the S55i complements not only Insight Series systems, but any system in which the customer demands an in-wall solution with no compromise performance. Previously, in-wall subwoofers presented a significant performance compromise. The S90i set the bar higher, and the smaller and less expensive S55i isn't far behind, offering a level of performance among in-wall subwoofers that was previously unavailable.

Please visit our Where To Buy page to locate your closest authorized Wisdom Audio dealer in North America, or International Distributor in markets outside North America.

S55i Specifications
All specifications are subject to change at any time, in order to improve the product.

Frequency response 30Hz – 80 Hz ± 3dB relative to the target curve
Impedance 8 ohms
Sensitivity 90 dB / 2.83V / 1m
Power handling, peak 240w
Maximum SPL 115dB / 30Hz / 1m
Shipping weight 43 lbs. (20 kg)


S55i .dwg, .dxf, pdf
To view the CAD drawings above, download SolidWorks eDrawings here.

All Model Dimensions

Owner's Manual
S55i Owner's Manual

Coming soon.