Ashley's Bookshelf Speakers:
Shelf and corner braces
Lots of yellow carpenter's glue!
Note the Jasper Circle Jig, perfect circles!
Some construction pics:
Scan Speak resistive vent and unmounted crossover
Drivers mounted ready for Clio testing
The crossover gets its own box.
Lots of soldering.
Ashley's second speaker project is the design and construction of bookshelf speakers based on the Dayton 8 inch (#295-310) and Dayton silk dome (#275-070).  The links immediately below jump to pages containing measured T-S specifications and specifics of box and crossover design plus the Clio measurements on the final product.  It should be noted that, even after extensive break-in, the woofer specs differ from the published values.  The tweeter specs also differ (Fs, anyway).  We selected the two lowest Fs samples from 10 sets of tweeters (the selected ones had Fs = 1050 to 1080 Hz).  Since Ashley wanted to cross over as low as possible (8 inch mid/bass) she elected to incorporate a somewhat steep 3rd order Butterworth alignment with a Zobel on each driver and additional resonant peak equalization of the tweeter.  Before adding the last filter noticeable resonance occurred at about 1000 Hz.  The rubber surround on the Dayton woofer could have accounted for some of this resonance, but it practically disappeared with the additional tweeter filtration.  Power handling by the tweeter should be considerably improved, as well.  The woofer is crossed over higher than the tweeter to help flatten response and to help with phasing.  To avoid additional crossover complexity and cost, Ashley opted to use a Scan Speak resistive vent to reduce the woofer/box resonance impedance.  The "aperiodic" vent also allowed her to keep her enclosures as small a possible.  The crossovers were mounted in their own boxes to allow later modification if desired and to further reduce the required speaker box volume.
T-S parameters:
Crossover design:
Sealed box details:
Clio test data:
Subjective listening experience:
I have set Ashley's speakers next to Farm's line array and my own Energy C-2 for A/B listening comparisons.

Observation #1: Ashley's speakers are very efficient (Clio testing reveals 6 dB more efficient than the Energy speakers) but are much less efficient than Farm's.

Observation #2: Ashley's speakers have extremely articulate bass, not deep, but very well controlled and crisp.  We'll follow up with some spectral decay waterfall plots when our Clio software upgrade arrives.

Observation #3: Ashley's speakers have midrange clarity and balance easily surpassing the Energy speaker performance  and rivaling Farm's array.

Observation #4: Ashley's boxes have considerably less wall vibration than the Energy speakers.   (I had thought that was one of the selling points of the whole Connoisseur line -----the C-2s were $600 per pair!)  Farm's array, of course, has almost no detectable wall vibration at the same SPL level.

Observation #5: Even my aged hearing appreciates the more detailed high end compared to Farm's full-range array.  I must concede that the metal dome Energy has a good high end, too.  The younger listeners have detected a harshness, however, in the Energy high end.  I attribute this to the 20k ring of the metal dome.  I can't hear 20k anymore, so I'm forced to rely on the opinions of those who can.

Which brings me to Observation #6: Every single listener (I polled at least 50 teens and a dozen fellow teachers) preferred the sound of Ashley's speakers to the Energy C-2s.  The opinions were divided when comparing Ashley's and Farm's.  I suspect that the novel look of the tower array added subjectively to the opinion-forming process.

Conclusion:
If I had been able to choose between Ashley's speakers and the Energys when I bought bookshelf speakers, I would have chosen Ashley's hands down.  NO CONTEST!!!  I'd have been willing to pay at least the same amount.  Her material costs were just a tiny fraction of the $600 I spent.  Everything taken into account, Ashley's material cost was under $75 per speaker (including box, paint, plexiglass, stuffing, drivers, crossover components, etc.).  Unfortunately, the DIY 2001 events are all back East.  The $150 categories would have a worthy challenger.
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