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Another contender in the high value 2 way monitor/bookshelf category, the Armadillo TM, featuring the Vifa XT25SC90-04 1" Dual Ring Radiator Tweeter and the Peerless 830656 5-1/4" SDS Woofer. Another collaborative project designed by Mark65 and myself, with Mark doing most (99.9%) of the heavy lifting on the crossover design, and a bit of final tweaking (for a purely educational experience) by myself.
This was originally meant to be a surround speaker to go with the Armadillo CC, and can be built sealed in as little as 6 liters, at the expense of the low end. I decided to do the first ones in a 10 liter ported cab, lined and fairly well stuffed, with a tuning around 55hz. This gives a nice 1 db bump in the bass that sounds surprisingly full with most normal music, fans of hip hop, dubstep, or electronica will probably want a sub with these. But for everything else, these seem to do the trick just fine on their own.
The overall dimensions are 8" W x 12" H x 10.5" D with a 2" dia. x 5" long port. The sealed version Would be about 6-7" deep and heavily stuffed. A single dowel brace to tie the sides together seems adequate with 3/4" panels. The woofer and tweeter are 6" and 2" from the top edge of the cabinet, with the tweeter flush mounted and the woofer surface mounted. The port is recessed into the back panel 1/4" and glued in, with a 1/2" round-over on the outside end.
The crossovers are quite reasonable with a low parts count, we modeled for a P-core on the woofer and an 18 gauge air core on the tweeter. I used Dayton poly caps and a mix of Dayton and P.E. resistors. The schematic shows 3-5 ohms on the series resistor, the sim reflects the as built value of 3.3 ohms, things don't change too much between 3-5 ohms besides the very top end flattening out a bit. As always, try it at 3.3 and adjust to taste.
The final bill of materials for drivers and crossovers comes in at just under $140. A pair of cabs can be cut from a 1/4 sheet of MDF, if you want to buy a full sheet you can have it cut into 24" sections for easy transport and have enough for a pair in one section. A handy panel may not be enough if they cut them to exactly 48" (instead of the full sheets 49" width) so keep that in mind.
Woofer 264-1078
Tweeter 264-1014
1.2mH coil 255-102
0.13mH coil 255-204
100 ohm resistor 017-100 (get 2 of these per speaker)
20ohm resistor 004-20
3.3uF cap 027-420
4.3uF cap 027-419
6.2uF cap 027-427
Padding resistor 004-3.3 (as built/modeled value)
This was originally meant to be a surround speaker to go with the Armadillo CC, and can be built sealed in as little as 6 liters, at the expense of the low end. I decided to do the first ones in a 10 liter ported cab, lined and fairly well stuffed, with a tuning around 55hz. This gives a nice 1 db bump in the bass that sounds surprisingly full with most normal music, fans of hip hop, dubstep, or electronica will probably want a sub with these. But for everything else, these seem to do the trick just fine on their own.
The overall dimensions are 8" W x 12" H x 10.5" D with a 2" dia. x 5" long port. The sealed version Would be about 6-7" deep and heavily stuffed. A single dowel brace to tie the sides together seems adequate with 3/4" panels. The woofer and tweeter are 6" and 2" from the top edge of the cabinet, with the tweeter flush mounted and the woofer surface mounted. The port is recessed into the back panel 1/4" and glued in, with a 1/2" round-over on the outside end.
The crossovers are quite reasonable with a low parts count, we modeled for a P-core on the woofer and an 18 gauge air core on the tweeter. I used Dayton poly caps and a mix of Dayton and P.E. resistors. The schematic shows 3-5 ohms on the series resistor, the sim reflects the as built value of 3.3 ohms, things don't change too much between 3-5 ohms besides the very top end flattening out a bit. As always, try it at 3.3 and adjust to taste.
The final bill of materials for drivers and crossovers comes in at just under $140. A pair of cabs can be cut from a 1/4 sheet of MDF, if you want to buy a full sheet you can have it cut into 24" sections for easy transport and have enough for a pair in one section. A handy panel may not be enough if they cut them to exactly 48" (instead of the full sheets 49" width) so keep that in mind.
Woofer 264-1078
Tweeter 264-1014
1.2mH coil 255-102
0.13mH coil 255-204
100 ohm resistor 017-100 (get 2 of these per speaker)
20ohm resistor 004-20
3.3uF cap 027-420
4.3uF cap 027-419
6.2uF cap 027-427
Padding resistor 004-3.3 (as built/modeled value)
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