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17
Speaker Building
Crossover Design
3
To begin the crossover design process,
I took measurements with The Pipe on the
floor and an Omnimic on a six-foot stand and
approximately two feet from it—about 45°
off-axis. I could have measured on-axis to
make a prettier, flatter frequency response
graph, but it wouldn’t sound that way from
where I typically listen from.
After playing with a couple of different
crossover options, I found that a simple
2nd-order filter for the tweeter and the woofer
would work perfectly. The tweeters have two
Audyn 3.9 µF caps (wired in parallel for a 7.8
µF value) in series, and a 0.47 mH 18 AWG
Jantzen inductor in parallel.
The two woofers on each side of the
amp are wired in parallel (which helps them
keep up with the tweeters) and have a 0.95
mH 18 AWG Jantzen inductor in series with
a 50 µF electrolytic capacitor in parallel.
Altogether, this approximates a 1,500 Hz
2-way crossover.
About the Designer: Chris Perez
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Parts List
Part #
Description
Qty
To be completely honest, The Pipe
sounded (and measured) pretty darn
good without the tweeters connected.
The highs were a bit muffled, and a
bit of intermodulation distortion (also
referred to as Doppler distortion)
could be heard. Adding the tweeters
and crossovers made The Pipe just
sing. Bluetooth syncs and streams
flawlessly, allowing me to keep my
phone at my side while using it as
the source.
I added grills and handles to protect
the speakers. The tweeter grills are
repurposed computer fan guards,
and the woofer grill is polished
steel shelving that I had found at
Mendelson’s Liquidation Outlet
). The PVC is finished
in Rust-Oleum
®
Satin Finish Blue and
Rust-Oleum
®
Crystal Clear Enamel.
Conclusion
4
110
105
100
95
90
85
80
75
70
65
60
55
50
180
120
60
0
-60
-120
-180
10
100
1000
10000
100000
Phase (Degrees)
SPL (dB)
Woofer+Tweeter SystemResponse
Back View
Chris Perez has built, taken apart, and rebuilt speakers for over 20 years, and is a former Parts Express Technical Advisor. Chris’s
creativity and attention to detail are second to none, and he usually finds ways for his speaker designs to bend the laws of physics.
Also mentioned in
this article
5
• Updated software and improved hardware
• Compact, portable, accurate, affordable
• Intuitive software—open the box,
start testing in minutes
• Perfect for setting up home theater systems
• Optimized for use with netbooks
and laptops
• Accurate response down to 5 Hz,
fully calibrated, includes FRD file
• For professionals and hobbyists—design
and tune speaker systems and arrays
Dayton Audio OmniMic V2 Precision Measurement System
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