Size Matters: Choosing the Right FFT for Bass
A common mistake is using a small FFT size (like 128 or 256) when trying to measure subwoofers. Because low frequencies have long wavelengths, a small FFT doesn’t have enough “time” to accurately resolve the frequency.
The Resolution Rule
- For High Frequencies: Small FFTs are fine and very fast.
- For Subwoofers: You need at least 32k or 64k FFT sizes to see the detail below 40Hz.
The Smaart v9 Way: Use **MTW (Multi-Time Window)**. Smaart v9 handles this for you by automatically using larger windows for the lows and smaller windows for the highs. It’s the “Set and Forget” way to ensure your sub alignment is mathematically accurate.