After completing a rather complex 3-way Open Back design, I wanted to design a satisfying, inexpensive alternative that could be built by anyone on a budget. Enter the CBS (Couldn't be Simpler) project.
Design goals:
All aluminum, high resolution drivers.
True Dipole throughout frequency range
No mid range suck-out experienced with many larger woofer, 2-way designs
Satisfying low end
Take advantage of AV receiver's existing electronic x/o
No additional passive shaping components
The drivers mount to a 3/4" MDF baffle measuring 24" tall by 10" wide. The woofer is mounted low to address floor-bounce and angled 5 degrees toward the listener. The full range driver is centered both horizontally and vertically on the baffle. The system is supported at 3 points using sorbothane pads. There is virtually no baffle noise at moderate volume.
A rather impressive Peerless 830987 3" all aluminum driver handles the full range duty at a cost of around $24 US per driver. Low frequencies are handled admirably by a HiVi M8N 8" all aluminum woofer, with an xmax of around 6mm, an Fs of 33 Hz and a measured Qts of around 55. This driver retails around $45 US.
As part of the minimalist concept, I run the Peerless driver from an A/V Receiver in pure direct mode (tone controls bypassed). The receiver's speaker type is set to small. The crossover frequency is set at 200 Hz. I use a single small plate amp to drive both HiVi woofers in parallel at a 4 ohm total load. The plate's crossover frequency is dialed-in to meet the roll-off of the Peerless driver and the level is matched accordingly. While this is clearly the most critical part of the setup, it can be done in a matter of minutes, with or without test equipment. I prefer plate amps that attenuate their slope at a rate of 24dB per octave, but I have also achieved good results with others at 12dB/oct.
Listening impressions are as follows: They have no right to sound this good, being so simple and inexpensive. The midrange is very authentic and low mids are driven with authority. Presentation is balanced and enveloping, especially with many jazz and classical CD's that have an emphasis on acoustic instruments. The timbre of both woodwind and brass instruments are also realistic. Vocal presentation is once again natural with no smearing. Resolution is high and they appear to image well. The peerless drivers crossed at 200Hz sound very comfortable in their skin, never straining or compressing at moderate levels.
This is my 2nd project using the Peerless 830987 drivers, and they continue to impress!
