I've recently scrapped a Wharfedale DX2 sub (70w, 8" driver 15l sealed cab). I transferred the driver to a 24l ported cab.
Wow!
The ported cab uses a 28w amp for bass, yet it outperforms the original 70w DX2. An LFE improvement was expected + 2-3db for the port. The results give me pause. Maybe throwing more power at the problem isn't the best first option.
Wow!
The ported cab uses a 28w amp for bass, yet it outperforms the original 70w DX2. An LFE improvement was expected + 2-3db for the port. The results give me pause. Maybe throwing more power at the problem isn't the best first option.
The power the speaker receives is the voltage squared/impedance.
Your sealed cabinet impedance is probably higher than the ported, so even with a greater voltage (+3dB) the actual power delivered to the driver may be less.
The output around Fb (port tuning) can be near +10dB more than a sealed cabinet (far more than you expected), which may sound as much as four times as loud with the same input level due to the subjective "equal loudness" contours of normal hearing.
In the example above, the 24L bass reflex (light gray) at 11volts input (30.25 watts into a nominal 4 ohms) is +6.7 dB at 43Hz than the 15L sealed (black) using 16volts (64watts into a nominal 4 ohms), twice the "power".
The bass reflex would easily sound more than twice as loud around 43 Hz, while at 20Hz the sealed would sound even more than twice as loud.
That said, most pop music has little content below 30Hz where the two match, so the bass reflex would sound considerably louder.
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