The Design: The driver's parameters were relatively easy to work with and didn't require anything overly elaborate in order to sustain a flat in-cabin response. After some modeling, I arrived at a fairly straight-forward rear firing bass-reflex design.
The Build: For starters, here's a shot of the binding process. With the low temperatures this time of year, I feel more comfortable applying pressure in more places and letting the adhesives set for approximately an hour per joint. Notice the ratchet bar on the far side pushing the two parallel walls apart to form a perfect 90 deg. angle:
This enclosure is predicted to sustain relatively high vent velocity along the bottom octave so proper aerodynamics will be of moderate importance. The outer vent flare is beveled out to a 1.5" radius while the bevel along the inner 90 deg. bend is beveled out to a 1" radius:
The structural advantage of small radius bevels such as these is that the flare is solid throughout and has more glue joint surface than a typical notch-bent panel. The enclosure, itself, is another one of my screwless builds, though a set of drywall screws is being used as temporary clamps along the base:
Along the outside, the enclosure features a 0.5" radius bevel which keeps the corners from snagging and protects the edges from chipping upon impact:
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( 3.3 / 6 )The Goal: The object here was to implement a 4th order blow-through design featuring a single JL Audio 13W7. Upon the client's request the design had to be symmetrical.
The Design: This began as a much larger blow-through design that the client purchased as a set of blueprints. He has since decided to go with a full build, thus, in lieu of shipping expenses, the original design had to be revised with a somewhat lower target size and weight.
The Build: Even in it's compact form, the enclosure would be quite ample and cumbersome. By the sheer virtue of the woofer's weight distribution in a vertical mounting configuration, the mounting baffle had to be double-stacked:
Since the enclosure won't ship pre-loaded with a woofer, the client will require access to the mounting baffle between the two chambers. The design features a removable outer rear stack which reveals a square access opening just large enough to fit the woofer through:
A 0.75" lip extends out above and beneath the rear wall of the enclosure so that a second outer baffle can be flush-mounted across it's full width forming a rather inconspicuous access panel:
With a blow-through configuration, the enclosure doesn't stand to gain any functional or aesthetic benefit from rounded-over edges. As such, all exterior right angles are retained.
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( 3.4 / 19 )The Goal: The client was looking for a strong 30Hz - 80Hz solution in his 2003 Civic Sedan, using a pair of 1510 series subwoofers from Digital Designs.
The Design: Upon the client's request, the enclosure was engineered around the principles inherent in my original "HellBoy" design, but with emphasis on the fact that it would fire into the trunk and not directly into the cabin. Space constraints presented another issue, however, one that could be overcome.
The Build: This build was another in a series of firsts; in case, the first screwless enclosure to feature wood bending. As this alignment will yield substantially high vent velocity, a 6" radius outer flare was implemented to keep down the audible turbulence:
The best way to keep a flush mount inset in perfect alignment with the woofer cut-out is to trace it with a rabbeting bit. Here you see a pair of standard mounting holes cut into the double-stack:
Once the enclosure is fully assembled, the mounting cut-outs are traced with a 0.75" rabbeting bit in multiple passes. Afterward, they are beveled out with a 0.25" radius round-over bit (as are the short outer edges of the enclosure.) The long outer edges are beveled with a 1" round-over bit:
In the end, we wind up with a sturdy build with no sharp edges for the carped to snag on as the enclosure is taken in and out of the vehicle:
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( 3.6 / 56 )The Goal: The object here was to sustain an even low frequency extension throughout a medium size room. In addition to all-around powerful bass, this enclosure needed to be suitable for music and movies alike.
The Design: After reviewing the client's room layout and the proposed subwoofer position, I arrived at a corner-loading bass-reflex design. In addition to the single 10" woofer, the enclosure would also have to house a plate amp, which I incorporated into the compression chamber.
The Build: This was already the second in the series of my screwless home audio builds. Here, you see a little bit of pressure applied to one of the panels:
As you can see, the design, itself, is quite rudimentary. I always tell my clients that complexity doesn't automatically translate to performance. I try to keep my designs as straight-forward as possible whenever I can and, luckily, achieving the desired results in the client's listening environment did not call for anything overly exotic:
The finished product was this single-axis bass-reflex with a plate amp cut-out centered along the side and a flush-mount inset for the woofer. The slot-loaded vent terminates at a 1.5" radius flare:
As a fun bonus, this enclosure was scheduled to ship around the time when Steve from Digital Designs was coming out for a visit. We postponed the shipping date so that both Steve and I could sign the enclosure.
From the right to the left, we have Steve Milton, his brother, and me. Oh, and the enclosure, of course.
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( 3.7 / 43 )The Goal: The client was looking to achieve "big sound" with a small sub inside of an '88 Honda Civic hatchback. In addition to out-performing the client's old enclosure, this new one was to remain musical and sustain a wide response range.
The Design: Even though the 8W7 bares a relatively low efficiency bandwidth product, the overall loading characteristics inside the cabin made it possible to horn-load this little woofer via a large throat chamber and a tight throat gap. The result was a rear-loading horn with a rather high cross-sectional expansion rate.
The Build: I decided to make this my first completely screwless car audio enclosure. Screws were used temporarily along the top and the bottom of the enclosure serving as vertical clamps while the vertical panels were clamped horizontally using a series of ratchet bars:
As you can see in the picture below, the horn's cross-section expands quite rapidly, going from 58cm^2 at the throat to 464cm^2 at the mouth--that's almost twice the woofer's effective piston area. The inner vertical edge of the mouth is beveled with a 1.5" round-over:
Once all the panels bonded, the screws were removed and the holes were filled with MDF paste. Since no counter-sinks were necessary, the holes could be kept very small and, once the MDF paste cured, it was sanded flush, leaving almost no trace:
A 0.375" radius round-over was used along all of the outside corners for a "soft" finish:
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( 3.7 / 42 )
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