The Armonicos, by Chuck Morris
These were inspired by the design theme of DIY Indiana, 2014 – to design a system based on a series network.
Spanish for “Harmonious”, the Armonicos represent my first full an attempt of design from start to finish. I wanted something unique in appearance and design, using mid-level priced components, and the ability to be replicated by others. I want to thank Ben for convincing me to try a series crossover design and for his very informative write-ups.
The drivers are the Eclipse, W6520R-4, 6.5″ woofer and SB Acoustics, SB26STAC, 1″ soft dome tweeter. I was introduced to the Eclipse woofer at Jeff Bagby’s crossover design seminar and felt it to be well worth its moderate cost. Both drivers exhibit a wide flat response with a generous overlap in freq. response and low distortion.
The enclosure is formed from a section of 10″ dia PVC pipe. MDF was used to form the top and bottom caps. A 1″ thick Oak baffle was inlaid for the front. Rustoleum Crimson metallic paint and ebony stain for the front and feet. They are ported using a 2″ dia flared port, down-firing and tuned to 42Hz. This gives an f3/6/10 of 39/34/30 respectively.
The crossover is a series design (per Ludicrosity rules) and is 2nd order on the woofer and 3rd order on the tweeter resulting in BW3, BW5 alignments, respectively. The tweeter is wired in normal polarity. The crossover point is about 1900Hz.
The cabinet is 17.8L (.63 cu ft) and is vented, tuned to 42Hz Chuck’s version used a PVC pipe as part of the enclosure, but we give you a more conventional box in the drawings.
The Bare Bones kit gives you the drivers and specified crossover parts. Chuck used the Sonic Caps on the tweeter leg and is an upgrade option. Here is what you get:
- 2 x SB26STAC Tweeters
- 2 x Eclipse, W6520R-4 Mid Woofer
- 2 x Crossover parts, featuring Solen Capacitors, “Zisters” and specified inductors.
- Complete plans
If you like, we can assemble and test the crossovers for you at an additional cost.