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The Amplifier: A sheet is available describing the 300 watt TOBY--Bash amplifier and its controls. The purpose of this sheet is to cover the system specifications and user application.
The Frequency Control: The crossover knob should be at or slightly below the 12:00 position. This is the way the amplifier achieves a flat response in the Toby CUBE 14. The frequency graph that comes with your subwoofer is made at the 12:00 position which results in 3 dB down points of 30 and 100 Hz. If you wish, you may experiment with other positions above or below the 12:00 position. The very low bass level will remain unchanged, but the level of the higher bass will decrease below the 12:00 position, and increase above it. At any knob position you will hear only low bass, because higher frequencies are rolled off very sharply at 24dB per octave.
The Enclosure: The CUBE measures 14 x 14 x 14 inches. Internal volume is one cubic foot. This is undersized for the two woofers, but the amplifier has enough power to make up for the droop at very low frequencies and deliver a flat response down to 30 Hz. The advent of low cost high power digital amplifiers makes this possible. The bonus for the engineer is a stronger, lighter cabinet. The bonus for the user is a modestly sized speaker system that is easy to place in the room, yet powerful enough for DVD movie effects.
The Woofers: The CUBE 14 uses two long throw ten inch proprietary drivers with rubber edges and carbon doped cones. They are mounted on opposite sides of the enclosure to prevent it from "walking" on a hard surface. Any motion of the cabinet means a loss of bass power and accuracy. Both ten inch drivers are active, and are capable of excursions greater than one inch.
The Placement of Low Bass: It is often said that you can place the subwoofer anywhere in the room because the lows are not directional. It is true that, often in movies, the sub might be "anywhere in the room" which has five or more speakers surrounding the listener. However, it is not a good idea for stereo, where the sub needs to be near the front pair of speakers. Placement away from the front speakers ignores the arrival times and the inverse square rule-the level drops 6 dB per doubling of the distance. If the sub is your coffee table, the bass will come early, and be many times louder than the other speakers. We recommend placing the sub between the front speakers or beside one of them.
Effects of Placement of the Subwoofer: For your stereo speakers we always suggest that they be placed where human heads are. This means 3 to 6 feet high and 2 or 3 feet away from rear or side walls--no higher or lower, or in corners. This minimizes strong reflections which contaminate the sound in shorter wave lengths. Bass waves are long-11 feet for 100 Hz; 22 feet for 50 Hz-so reflections are not an issue with the sub. Go ahead and try a corner first. The bass will be the loudest and lowest in harmonic distortion. If the frequency balance with corner placement is poor in the room, try a position along a wall.
Disturbing the Neighbors: We already know the bass is not directional, so you can't "aim" it away from your neighbors like a tweeter. Fiberglass insulation in the walls has almost no effect on low frequencies. Placing the enclosure on a rubber pad has no effect, because the speaker cones radiate the bass, not the cabinet. Carpet or hardwood makes no difference.
Closing: A good subwoofer should be so low in distortion that its presentation should seem effortless. Although it is special to bring extended low frequencies in the room, the best part is the improved clarity of the small speakers which don't have to make bass and mid range from the same driver. The MUSIC is the winner!
Support: I'm sure you'll have more questions, so e-mail them to tobycorp@sbcglobal.net. Maybe I'll add them to this page. Toby Guynn Feb. 14, 2004