What is the best size of subwoofer and where do i put them?
Subwoofer design and placement have developed rapidly over recent years. Today we have much more control over how this important band of frequencies is deployed. So how we can deliver a better bottom end?
Bass frequencies are typically those below about 250 Hz, but I want to focus on sub bass frequencies typically between 20 and 100 Hz. Our Dual 21 inch 4000 RMS sub woofer delivers over 139dB SPL and operates sweetly between 29 – 200 Hz.
The nature of the way in which we hear means we don’t perceive all frequencies equally and humans are less sensitive to frequencies below 100 Hz, which is why this region requires
special attention. Standard PA loudspeakers will go down to a reasonable frequency for reference purposes, but both will always benefit from the addition of subwoofers to enhance the bottom
end. Amplifiers designed to power subs tend to be lighter and more powerful than ever before and many have built in crossovers especially for subs.
For most venues we supply, large sub bass loudspeakers are needed to produce low-frequency sounds. Recently we took a step up from the traditional 18″ Sub woofer to the more powerful 21″. The issue remains the medium through which sound travels. Air is an inefficient conductor of vibrations, and bass vibrations are relatively slow, therefore, much more energy is needed to produce bass frequencies that match up to the same level as the corresponding higher frequencies. For this reason, we advise the use of 21″ or 18″ drivers to move much more air and give everyone the expected sound.
The best place to position the sub cabinets remains on the floor. Placing any loudspeaker against a large surface area results in a 6 dB increase in the radiating energy
For example, outside four subwoofers on the floor and close to a vertical surface could provide the equivalent output of as many as sixteen identical subwoofers. But a word of caution if your mixing from 100ft away and getting 100 dB SPL the listeners at the front of the venue will be getting 120dB SPL and those at the back 200 feet away will only be getting 94 dB SPL. Indoors the difference would not be that extreme.
If time and money is no object flying bass speakers is an option below the array but due to the weight putting subs on the floor remain the simplest and highly effective solution.