#RE BOX CALCULATOR DRIVER#

Speakers with loose suspension have a higher Vas and use larger enclosures. Stiff speakers have lower Vas and tend to use small enclosures. Vas is the volume of air that has the same compliance as the speaker's suspension. You should notice that, unlike sealed enclosures, the impedance is lowest at the resonant frequency. This image (below) shows the impedance curve for a ported enclosure. Enclosures of different sizes will produce different resonant frequencies.

#RE BOX CALCULATOR DRIVER#

You can see how the resonant frequency shifts when the driver is mounted in an enclosure. The image below shows the impedance curve with a woofer in 1 ft^3 and in an infinitely large enclosure. The fc is higher than the fs with a given driver. The voltage applied to the speaker is constant for all frequencies.ДЎ5Hz 25Hz 35Hz 45Hz 55Hz 65Hz 75Hz 85Hz 95HzДЇc is the resonant frequency of the driver in a sealed enclosure. You can see by the bar graph that the current flow through the voice coil is the least at resonance. Put your mouse/cursor over the different frequencies below the following impedance curve. The image below shows how a speaker's impedance changes across the audio spectrum. The speaker's impedance may go from 4 ohms to more than 20 ohms at resonance. At resonance, the speaker's impedance increases dramatically. I would strongly recommend reading it before you continue with this page.ДЇs is the resonant frequency of a speaker in free air (not in an enclosure). If you haven't already read the speakers page of this site. Understanding the Thiele/Small Parameters

Re box calculator