Sixth-Order Bandpass Subwoofer Enclosure Design Calculator
|Explanation of Terms|
|Qts, Vas, and Fs, are the electro-mechanical parameters for your woofer. They are also commonly referred to as the "Thiele-Small" parameters. You can get these from the paperwork that came with your speakers, from the dealer where you purchased your speakers, or from the manufacturer of the speaker (they are sometimes hard to contact, however).|
|F3(L) - the frequency where the response is down by 3 dB (on the low end of the passband). This will be the first number in the "Passband" box when you calculate an enclosure.|
|F3(H) - the frequency where the response is down by 3 dB (on the high end of the passband). This will be the second number in the "Passband" box when you calculate an enclosure.|
|Vf - the internal volume of the front chamber of the enclosure.|
|Vr - the internal volume of the rear chamber of the enclosure.|
|Fb(F) - the frequency that the vent in the front chamber of the enclosure needs to be tuned to.|
|Fb(R) - the frequency that the vent in the rear chamber of the enclosure needs to be tuned to.|
|Passband - refers to the range of frequencies that will be allowed to pass through the speaker system (the frequencies you will be able to hear/feel). Any frequencies above or below the passband will be attenuated (reduced).|
|Gain - the amount of boost(or in some designs the amount of attenuation) in sound pressure level(SPL). This is usually referred to in speaker design with other terms, which serve to make it a valid reference point.|
A typical specification for a bandpass enclosure would be :
Efficiency/Sensitivity : 94 dB @ 1W/1M.
This means that this design is capable of creating a sound pressure level of 94 dB when a signal of 1 watt is applied to it, and is measured with the measuring instrument 1 meter (approximately 3.28 feet) away from the speaker system.
Typical Sixth-Order Bandpass
| This style of enclosure is patented by the Bose Corporation, information provided is for personal use only.|