3-way Vented Floorstanding Speaker - Results

The results compare very favorably with the initial goals. More importantly, I'm very happy with the sound of these speakers, though I'm naturally biased :) The bass is tight, deep and not boomy. Telarc's 1812 cannons are impressive. High volume are just as nice. The ScanSpeak tweeter is sweet but not overly bright. I could listen to these speakers all day without fatigue.

These speakers are currently powered by a 100 wpc Pioneer integrated amp. The room measures roughly 25 by 12 feet and has a sloping cathedral ceilings up to about 15 ft. Logistical reasons have forced me to place the speakers about 6 feet apart, and some 20 feet from the listening couch which is against one wall. One speaker is near a wall while the other is almost centered between the 12 ft span and some 4 ft from the rear wall. From the couch, imaging in this setup is mediocre at best. This is not surprising given the relative distances involved. Increasing the seperation of the speakers to at least 9 feet by moving the speaker from its central location towards the other wall significantly improves imaging, despite the 20 ft couch distance. This is the setup I use when doing real listening (which is when the kids are tucked into bed and the speaker can be safely relocated).

Final external dimensions are 16.25 inches deep (16.75 at base), 11.75 inches wide (13.375 at base) and 50.5 inches tall. Approximate internal volume is 2.9 cu. ft. for the woofer and 0.25 cu. ft. for the midrange. Finished weight is over 75 pounds per speaker.

Cost (in USD) works out to - $52 ( AC-10 , on sale), $38.50 ( 5N313 , on sale), $53.75 ( D2905/9000 ), $30 (wood, MDF, hardware, etc.) and $100 (crossover) or $274.25 per speaker. Crossover design was $35 from Madisound.

After breaking in the speakers with a few days of listening, I tried to measure the frequency response with a Radio Shack handheld SPL meter (cat. 33-2050) and Stereophile's Test 2 and 3 CDs. The SPL meter is rated at 32Hz to 10 KHz +-3 dB and yielded a measured response of 89.5 +- 5 dB from 32Hz to 10KHz. Measurements were made in-room at 1 meter and 2.83 V (1KHz) and thus suffered from room interaction. Measurements taken below 32 Hz and above 10 KHz dropped immediately, showing the limited range of the meter. There was 5 dB dip in the 125 to 250 Hz range probably due to room suckout. Placing the speaker adjacent the wall exhibited a reinforced low end, yielding a +5 dB bump in the 50 to 100 Hz range and removed the 125 to 250 Hz dip mentioned above. There was also a +5 dB peak centered at 6300 Hz. My wife and I then did some listening and could not hear this peak from the test CD. We concluded that this was most likely due to the inaccuracy of the SPL meter Unfortunately, I did not have the chance to measure these outdoors to compare them to the LEAP predicted response - maybe some day.

In summary, I'm extremely pleased with the entire project. The sound of these speakers rivals those of commercial speakers costing a while lot more. The results are extremely satisfying, and the accessible crossover means that future crossover tweaking is still possible (though not planned).

29-September-2000

Note: The contents in these pages are provided without any guarantee, written or implied. Readers are free to use them at their own risk, for personal use only. No commercial use is allowed without prior written consent from the author.