- 15′ room will cancel a 75 hz sound wave
- 20′ room will cancel a 56 hz sound wave
- 25′ room will cancel a 45 hz sound wave
- 30′ room will cancel a 37 hz sound wave
- In every case, the nearby frequencies will also be attenuated
- Phasing and position of each subwoofer is critical.
- A partially out of phase subwoofer will cancel some lower frequencies.
- Two subwoofers are typically required to achieve an ideal response curve.
In the field of sound system engineering, bass content is generally the most difficult to reproduce in sufficient quantity because of the nature of how humans hear low frequencies. We hear bass notes ever more softly as the frequency decreases. In particular, low-pitched percussion instruments present a significant challenge because their sharp transients get smeared by low-pass filtering. For these reasons, and because of the methods used to mix and master a recording, these instruments can sound noticeably artificial.
SW2 provides an improved method for the acoustic reproduction of low-pitched percussion instruments, a method that will restore their transient response and the associated acoustical energy that is partially lost during the recording and reproduction process.
It may require up to three times the average power being consumed to properly amplify an instrument like the bass drum. When driven to high output levels, even superior equipment can generate distortion that will diminish the clarity of a recording. This is why recordings are mastered with limited dynamic range, in order to prevent the distortion that would occur while amplifying those signals. In contrast, when listening to a live performance, instrument volumes are managed so that the listener’s ears aren’t pierced by middle frequencies like vocals, while drums are amplified to generate tremendous acoustical energy. This is one of the reasons why a live performance is so impressive. The setup for a live performance provides the equipment necessary to allow most instruments to be reproduced independently. Those signals have a dynamic range limited only by the equipment being used. In order to overcome these problems inherent in the reproduction of low-pitched percussion instruments, SW2 was designed.
If you have bookshelf speakers, set your receiver’s internal front speaker setting to “SMALL”. This protects the small drivers (6” or smaller) from damage due to excessive power pushed into their voice coils. Otherwise, set this parameter to “LARGE”.
The “small” setting engages a high-pass filter that smears the signal presented to your front speakers. All speakers have what is called a “mechanical” crossover point (low frequency roll off). This means that the characteristics of its largest driver along with the tightness of the air in the enclosure will not allow that driver to vibrate below a given frequency. If your front speakers have an 8” driver or larger, we highly recommend that you deliver them a full signal. When blended properly with a subwoofer, this will provide superior results.
The life of all electronic equipment is decreased when the circuits frequently heat up when turned on, and cool off when turned off. Set your subwoofer’s main switch to ON instead of AUTO, and use decent surge protectors. We also recommend that you initially set the phase to -180 and the crossover frequency higher than you think it should be on your subwoofer. This compensates for some “phase shifting” that occurs as an accidental side effect of the crossover’s electronics.
Every subwoofer has it’s own distinctive sound – just as every loudspeaker does. Some sound muddy, others don’t. Listen to them closely before you buy! We recommend at least 300 watts of continuous power because this tells you that the sub is built well enough and is durable enough to handle serious power and it should then last 20 to 30 years. We also recommend 10″ or 12″ drivers because these move a sufficient amount of air at low frequencies. Drivers larger than 12″ have more weight and inertia and require enormous amounts of power to vibrate them at over 90 times per second.
All speakers operate on alternating current that is pushed by a voltage of between +/-18V. This current vibrates back and forth through the wire at many different frequencies simultaneously. Imagine that current traveling the entire length of your wires at over 20,000 times per second. To do this, the current needs a wire of almost 1/4 inch in diameter or else the signal can loose its strength and clarity. That’s why you need good wires, but you don’t need gigantic wires the size of a garden hose.
Here’s where you need to spend some money. If you invest in a good pair of front speakers, you will enjoy them for 20 to 30 years. You must really take your time to find what’s right for you. We recommend that you listen to some very clean recordings at high volume.
Did you know that every person’s hearing is slightly different? This is due to factors like the size and shape of your ears and eardrums, the environmental noise you are subject to, and the eardrum’s loss of elasticity with age. It’s kind of similar to how everyone’s voice is different. For this reason, a given speaker will sound slightly different to you than it will to someone else. So you need to find the speaker that “sounds the best”, not “has the best specs”. The specs can be very misleading because most speakers are rated “@ 1 watt @ 1 meter”. This gives you no idea if they will distort at 100 watts at 4 meters.
The most difficult task for a speaker to perform is to present a soundstage. A pair of good speakers should be able to make it sound as if the lead singer is standing 10 to 15 feet directly in front of you, and each instrument has its own place on the stage. Here are a few great recordings:
A rainy night in Georgia (Soul Book – Rod Stewart).
I can’t tell you why (Hell Freezes Over – The Eagles).
Can’t stay away from you (Greatest Hits – Gloria Estefan).
More to come!
Room Cancellation problems
Subwoofer Integration problems
A ten minute phone call is all it takes. Describe your room dimensions and speaker placement, and we will tell you if we can improve your sound system. There is no charge for the call.