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Loudspeaker Designs and Articles for the DIY Enthusiast
The
Mavericks
A Design utilizing both
Quasi-Transient Perfect
&
Conventional Crossovers
Cabinet Construction:

Wayne Wendel was responsible for the gorgeous cabinets. Thank You Wayne!!!
I left him with a crude drawing of the cabinet design, and gave him free reign over the actual construction. As you can see, his imagination and abilities
resulted in a design which garnered many compliments at the 2009 DIY Iowa get together. It was also his idea to build matching separate enclosures for
the crossovers. -Another great idea, as it made crossover modifications a snap to accomplish. Speakon connectors were utilized for simple, one plug
connection between them and the speakers.
The enclosure houses a transmission line for the woofer, and a
sealed cab for the midrange. The TL is a classic tapered line with a
10;1 taper ratio, and is approximately of the same 48 liter volume as
a similar vented enclosure, so for once there was no size penalty for
using a TL design. The line has only one fold and exits on the lower
back of the enclosure. I used Martin King’s TL alignment tables for
this design, but chose a slightly lower tuning then recommended by
the tables. While measuring the actual f3 can be problematic, the
audible performance suggests significant output into the low 30’s.  

The sealed mid enclosure, with a volume of about 7 liters, might be
considered by some quite large for a 4” driver. I found it was ‘just’
adequate to mitigate the typical issues with reflection and standing
waves which can plague sealed designs.

As built, the front baffle and top are 1.5” thick, while, the sides are 1”
thick. The actual enclosure is ¾” MDF which is covered on the front
and top with ¾” solid wood, while the sides are finished with ¼”
veneered plywood.

I fussed for some time with the stuffing, and ended up with stuffing
the front half of the woofer line only. I added a 1” piece of foam
directly behind and below the woofer keep the polyfill from shifting
too much. Figure about one and a half to two bags of polyfill per
woofer line. I lined the sides and back of the mid enclosure with 1”
foam, and stuffing the remaining space with polyfill. There are 2
braces in the woofer enclosure, one running from the front baffle to
the TL divider panel a couple of inches below the woofer cutout, and
one running from side to side several inches below that. The extra
enclosure thickness really tightened up the bass and midrange, so I’
d recommend staying with those thicknesses.
The enclosure houses a transmission line for the woofer, and a
sealed cab for the midrange. The TL is a classic tapered line with a
10;1 taper ratio, and is approximately of the same 48 liter volume as
a similar vented enclosure, so for once there was no size penalty for
using a TL design. The line has only one fold and exits on the lower
back of the enclosure. I used Martin King’s TL alignment tables for
this design, but chose a slightly lower tuning then recommended by
the tables. While measuring the actual f3 can be problematic, the
audible performance suggests significant output into the low 30’s.  
Links to:
Design Goals and Driver Selection
Cabinet Construction and Drawings
Crossover Design 1
Crossover Design 2
Bill of Materials
Measurements
Listening Impressions
Click on drawing above for the full size drawing, plus the working drawings