Home
Back
Sealed Box Volume Formula:
| From: | To: |
The Subwoofer Box Calculator helps determine the optimal sealed enclosure volume for a subwoofer based on its Thiele/Small parameters. Proper box volume is crucial for achieving the desired frequency response and sound quality.
The calculator uses the sealed box volume formula:
Where:
Explanation: This formula calculates the ideal sealed enclosure volume that will produce a flat frequency response (Qtc = 0.707) for the given subwoofer parameters.
Details: The enclosure volume significantly affects the subwoofer's frequency response, power handling, and transient response. Too small a box increases Qtc, resulting in a boomy sound, while too large a box reduces efficiency.
Tips: Enter Vas in cubic feet and Qts (typically between 0.2 and 0.6 for most subwoofers). Qts must not equal 1 (division by zero). For ported boxes, additional calculations are needed.
Q1: Where can I find Vas and Qts for my subwoofer?
A: These parameters are usually provided in the subwoofer's specifications sheet or can be measured using specialized equipment.
Q2: What if my Qts is exactly 1?
A: The formula becomes undefined at Qts=1. In practice, most subwoofers have Qts values significantly different from 1.
Q3: How does this differ for ported boxes?
A: Ported box calculations are more complex, involving tuning frequency and port dimensions. This calculator is for sealed enclosures only.
Q4: What is a typical box volume range?
A: For car audio, sealed boxes typically range from 0.5 to 2.0 cubic feet depending on subwoofer size and parameters.
Q5: Should I add volume for bracing and the subwoofer itself?
A: Yes, the calculated volume is net internal volume. You'll need to account for speaker displacement and any internal bracing when building the box.