Active 2-Way Desktop Speakers with Micro Subwoofers

This is a compact 2-way desktop speaker using the Tectonic TEBM35C10-4 BMR 2" Full-Range Speaker and the Tang Band W3-2052SC 3" RBM Subwoofer. When paired with an appropriate DSP crossing the two drivers at approximately 300Hz, this speaker can achieve a flat frequency response from 40Hz to 20KHz, which is incredible for a speaker of this size. This is NOT an incredibly loud speaker. Due to the limited displacement of micro-subwoofer drivers, these are limited to around 80dB before distortion becomes noticeable at low frequencies. If you use less bass at louder volumes, they can easily be used at higher SPL. Approximate speaker dimensions are 7.5" x 4.5" x 6" H x W x D. Bill of Materials: Electronics - Dayton Audio KABD-430 All In One Amp/DSP (Qty. 1 per pair) (or separate amplifiers and DSP)

Electrical - Parts Express speaker wire terminal #260-301 or #260-302 (Qty. 4 per pair) - 18 AWG wire (Qty. 4' per pair) - Solder - Note: Spade connections could be used instead of direct soldering. I did not attempt to identify the correct size spade terminals.

Drivers - Tectonic TEBM35C10-4 (Qty. 2 per pair) - Tang Band W3-2052SC (Qty. 2 per pair) - Dayton Audio ND90-PR (Qty. 2 per pair)

Mechanical & Miscellaneous - M3 x 5 x 4 LG heat set inserts (Qty. 36 per pair - same as Voron BOM spec) - M2.5 x 4 heat set inserts (Qty. 8 per pair - for Tectonic driver. Designed for CNC kitchen ones) - M3 button head cap screws (Qty. 36 per pair. Various lengths; I recommend getting a set like this: https://a.co/d/09dy4BRt) - M3 washers (Minimum qty. 8 per pair - included in the above M3 screw set) - M2.5 x 8 or M2.5 x 6 button head cap screws (Qty. 8 per pair) - 5mm wide foam tape - 2mm or 3mm thick (Qty. 5' per pair) - Hot glue (seals the Tectonic driver's wire pass through hole) - Polyfill (Qty. ???)

Generic Print Settings - Use whatever filament you deem appropriate for your intended use area; i.e. don't use PLA in a hot car. I prefer to use ABS or ASA. - Print the boxes on their backs with as many walls as needed to make the vertical walls solid. Use 40% infill to make the rear rigid. Supports may be used for the baffle mounting lugs. - Print the baffles upright with the same settings as the boxes. Supports should be used.

Generic Assembly Instructions - Install all heat set inserts. - Solder wires onto the drivers and assembling the drivers into the baffle. Note driver terminal polarity. Washers should be used under the heads of the M3 screws used to mount the subwoofer driver to increase bearing area. Leave sufficient extra wire for ease of assembly. It can be trimmed later. - Seal the Tectonic driver's wire penetration with hot glue or equivalent. This is critical to sealing the speaker as a whole. Do not skip this. - Add foam tape in the groove around the front of the box. Do not leave gaps. - Route the wires through the back of the box. Trim to an appropriate length. Solder each driver's set of wires to the binding posts, maintaining proper polarity. - Screw the binding post terminals onto the box. Label each terminal "W" and "T" for "woofer" and "Tweeter" for easy reference later. - Lightly stuff the box with polyfill. Ensure the polyfill surrounds the wires to prevent rattling. - Secure the baffle to the box. - Install the passive radiator, including its weights and gasket.

Other Notes The Tectonic full-range is quite a bit more sensitive (read: louder) than the subwoofer. Additionally, baffle step losses mean the output of the subwoofer is much reduced compared to the full-range. As such, the DSP should lower the output of the full-range driver. My DSP is configured to lower the output of the Tectonic driver by 16dB after the crossover. Your mileage may vary.