Last Updated on August 26, 2025 by DB DYNAMIX AUDIO

Introducing our first blueprint design for the site, "The Labyrinth Infra Resonator".  The design is based on a typical Helmholtz resonator that takes advantages of a lengthen, low volume compression chamber to increase control and alter the phase before the vent resonances of the long, massive port take over and reinforce the bottom end . 

I modeled this design with the intention of mimicking the low frequency extension of an infinite baffle subwoofer system in an automobile, so expect this design to be 2-3 db down from around 38 to 30 hz in comparison to a typical 33 hz tuned ported box for the same driver(s).  Above around 38 hz, the response resembles an acoustic suspension up until around the 70 hz region where a huge vent resonance peak occurs (typical of designs that utilize extremely long ports) so it would be wise to keep this in mind when setting your eq and crossovers to help blend it into your midbass and front stage.  Also as you would expect from any bass reflex design, group delay will impact the sound in comparison to an infinite baffle setup but the group delay models slightly better than a typical 33 hz tuned ported box, especially in the 50-30 hz region.

The strengths of this design are in its bandwidth as it has an estimated bandwidth between 70-17 hz.  Its biggest strength is in its efficiency at 30-17 hz.  The amplitude response graphs I modeled of this design and a standard 33 hz ported box showed similar output at 30 hz for both design alignments then the 33 hz ported box dropping to 4 db down at 25 hz and then to a little bit over 10 db down at 20 hz.  Bottom line is that this box design should move massive amounts of air.

This box is intended for 2 12 inch subwoofers.  Drivers with a minimum of 14-16 mm of xmax are recommended and power kept at its typical rms.  A single 15 would also work in this box but I recommend a driver with a minimum of 20 mm of xmax in that case.  Any of the monster spl subs that are available today will work fine with this enclosure but may sound a bit peaky within 3-5 hz above and below 20 hz due to the way they were designed.  The limiting factor with those drivers would be mounting depth since this box only offers less than 12 inches of depth after you take inconsideration spacing if a pole vent is present.

Please keep in mind that everyone will have different results with this enclosure design.  I tried to design it based on what I feel would be the best balance I could achieve for the widest selection of drivers available and the most common installations they would be used in  Some drivers may excel in this enclosure and other may not.  There are also a multitude of other factors to take into consideration such as the listening environment you intend on using this design in that includes things like the losses from panel vibrations, absorption losses due to various materials and the actual physical dimensions of the environment which can cause constructive and destructive interference at various frequencies.  Regardless, be safe testing it out and have fun experimenting.  There are many more crazy, out of the box thinking, enclosure designs on the way!

Enclosure Cut Sheet Dimensions

External Dimension of Enclosure When Completely Assembled:  40 inches wide x 18 inches tall x 24 inches deep

All dimensions are assuming 3/4" building material is used for all of the components.

2 front speaker baffles (red):  16.5 inches tall x 33.25 inches wide

2 top/bottom panels (brown):  40 inches wide x 24 inches deep

1 port side wall (teal):  23.25 inches deep x 16.5 inches tall

1 internal port side wall (blue):  18.75 inches deep x 16.5 inches tall

1 internal rear port panel (pink):  28.75 inches wide x 16.5 inches tall

1 internal port panel (yellow):  28.75 inches wide x 16.5 inches tall

1 side wall panel (purple):  23.25 inches deep x 16.5 inches tall

1 back wall panel (green):  38.5 inches wide x 16.5 inches tall

Design Notes:

Although I did not include 45 degree angles or rounding of any edges in this blueprint design,  I highly recommend you include them in your construction as it will help with the overall sound quality and efficiency of the enclosure.