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8" Speaker using Inexpensive Components

I built this speaker with the idea that a good sounding speaker didn't need to use expensive components.  I plan to use this a for background music while I am working at the computer/workbench. 

I have been doing some testing and the numbers look really good and it sounds great (better than my KRK Rokits 6's)

8in Speaker 

Here is the MEASURED frequency fesponse which is flat (+/- .5dB) between 50Hz and 15KHz. The dips between 1k and 2k aren't real -- they are reflections since I don't have an anechoic chamber for testing.  They move in frequency depending on microphone/speaker position.  Measurements were taken using a Soundblaster SB0490 USB sound card for the output and a Behringer ECM8000 Reference Microphone connected to a Blue Icicle (USB audio input).  The sweep was done using DFFS3 software (trial mode).  I like this software and would normally purchase it but I can't justify the $330 price.  I have been looking at TrueRTA but it doesn't seem to have a slow sweep option.

8in Speaker Test Setup  8in Speaker Frequency Response Plot 

Specifications
External Dimensions
 24 15/16" Tall x 14 13/16" Deep x 10 3/16" Wide
Internal Dimensions 24" Tall x 13 3/4" Deep x 9 1/4" Wide
Internal Volume 1.683 cu. ft. (not including vent/speakers/etc.)
Port
 Rectangular 9 1/4" Wide x  1" Tall x 4" Deep
Fb
 55Hz
Power Handling
 60Watts RMS
Impedance
 8 Ohms
Damping Material
 Moderate Damping with Polyester Batting

This was built in a 2-way configuration with a 3500Hz crossover point.

Parts List
1/2" Baltic Birch Plywood (actually 12mm)
 Free (Already Had)
Goldwood 2" x 5" Piezo Tweeter (Parts Express 270-041)
 $2.25
GRS 8" Full-range Speaker (Parts Express 292-430)
 $12.50
Jansten 0.35mH Inductor (Parts Express 255-030)
 $4.42
0.22uF 100V Capacitor (Parts Express 020-1840)
 $0.29
100ohm 1 W Resistor (need 2 of 10 pack) (Parts Express 003-100)
$0.69
Square Speaker Terminal (Parts Express 260-297)
 $1.21
Misc 18ga Wire
Free (Already Had)
Polyester Batting
Free (Already Had)
Handle (from old kitchen cabinet)
 Free (Already Had)
Total
 $21.36
 

I'll put up drawings and a Solidworks model of the design when I get it documented.  Here are some more photos in the meantime.

routed panel panel test fit  back of front panel  back view  front of speaker

and one more photo for Jason who said the port didn't show up well:

8in speaker port

and a video of the routing: