Loudspeaker Designs and Articles for the DIY Enthusiast
Jim Holtz's:

Big sound from a monitor sized
speaker design using high
value drivers.
Driver Selection

Since this was a design intended to give top performance in a monitor sized cabinet at an affordable price, we chose the NE149 based on feedback
from others that have compared it favorably to its high end siblings from Scan-Speak. The NE149 was an unknown quantity, so I even went so far as to size
the mid cut out to accommodate  SB Acoustics, Scan Revelator and Seas Excel 5 ½” drivers in case we were not satisfied with the NE149 performance. The
NE149 exceeded my expectations. It tested great and sounded better.
We also chose a Dayton RS28F tweeter and the trusty Dayton RS225-8 woofer to support the mid range. The two Dayton drivers are proven performers
whose sound quality far exceeds their price point. Both are superb drivers when used as designed that would require several times their cost to better their
performance, IMHO. I keep looking for a better 8” woofer that is low distortion, has a low F/3 and decent xmax that requires a reasonable sized cabinet for
bass extension and I can’t find one that doesn’t cost several times the cost of the new RS225-8. I also find the RS28F to be a real over achiever. Both offer
superb performance at affordable prices.

Curt: The advanced frame design of the NE149 made it look like an excellent candidate for the 6" tunnel mid enclosure Jim and I had in mind. Our concern
was that a large magnet assembly would impede the rear pressure wave and cause cavity resonance in the cylindrical enclosure. During testing with the
SB15 with its larger ferrite magnet, this proved not to be the case however. The design certainly could have moved ahead using the SB15, but at that point
we were too enamoured by the Vifa's midrange and elected to keep it in the midrange slot.  
Links to:

Main / Design Goals

Driver Selection

Cabinet Construction

Crossover Design


Listening Impressions