LCM Monitor Speaker - 40Hz waveguide - Bluetooth - DSP

LCM Nearfield monitor speaker

This is a near field mini-monitor, designed for excellent bass response, and intended for use at a desk or console. They are suitable for desktop, shelf, or wall mounting and optimized for small to medium sized rooms. The 55cm waveguide port is tuned to 44Hz and provides bass down to 40Hz in a small 14cm x 19cm x 17cm package (5.5 x 7.5 x 6.7 inch).

The recommended 4 channel DSP amplifier has bluetooth and 3.5mm input and functions as the crossover to split the signal between woofer and tweeter at 200Hz. (It will be possible to use other amplifiers but you will need to have a crossover of some form.)

The speaker prints in 2 halves which glue together with a tongue and groove joint. I also made a version for wooden side panels. This will cut the amount of plastic needed and the print time. I've included desk stands with 5 and 10 degrees tilt.

If you like it, please hit like!

I suggest using this amplifier with the Sigma Studio DSP project:
https://www.thingiverse.com/thing:4761687
There are two versions of the DSP project, one which uses a rotary encoder and switches to control EQ and tone controls, and a simple version with only has a volume control. (Remove the .txt extension from the .dspproj files to open them in Sigma Studio.)

Video shootout with 10" Pro Studio Monitor and with BL2

Bill of materials

Drivers:
Woofer:
https://www.parts-express.com/Tang-Band-W3-1876S-3-Mini-Subwoofer-264-909
Tweeter:
https://www.parts-express.com/Tectonic-TEBM35C10-4-BMR-2-Full-Range-Speaker-4-Ohm-297-216

Bill of materials, fully printed version, per speaker:

• Tang Band W3 1876S 3" Subwoofer driver
• Tectonic TEBM35C10-4 2" BMR driver
• Glue
• Speaker wire
• Polyfill speaker stuffing, or similar, enough for 0.4 liters
• 4x M2 x 8mm screws for tweeter
• 6x M3 x 10mm screws for woofer

Bluetack or foam speaker gasket material Bill of materials, wood panel version, per speaker:

Tang Band W3 1876S 3" Subwoofer driver

• Tectonic TEBM35C10-4 2" BMR driver
• Glue
• Speaker wire
• Polyfill speaker stuffing, or similar, enough for 0.4 liters
• 4x M2 x 8mm screws for tweeter
• 6x M3 x 10mm screws for woofer
• Bluetack or foam speaker gasket material
• 2x Wood or MDF panels 19cm x 17.2cm (approx 7.5 x 6.7 inch)

(Optional) 20x M3 x 10mm screws for side panels

Printing and Assembly

Printing:
Use at least 3 perimeters, I recommend at least 30% infill.

After printing:

Note: for good bass performance it is important to make sure all glue joints are airtight, as well as the gaskets for the drivers and the cable exits.

Clear any stringing from the port

• If making the half-wood version: Glue on the side panels, making sure to get a good seal all around. Use some glue between the wall of the tweeter chamber and the panel to prevent buzzing. It's probably a good idea to apply more sealant after the glue has set.
• Put masking tape on the outside around the perimeter of the glue joint, to avoid dribbles making a mess of the outside.
• Glue the left and right half together using plenty of glue, I suggest clear gorilla glue or slow cure epoxy. Clamp the the two halves together until fully dry.
• Push the speaker wire through the holes
• Use bluetack or foam to make gaskets for the speakers
• Stuff the tweeter chamber only with polyfill or teddy bear stuffing.(The bass chamber should not have any stuffing.)
• Connect the wires to the drivers
• Screw the drivers in place
• Seal the holes for the wires with bluetack or silicone

Category: Audio