But it captures the frequencies. It doesn’t add lower frequencies.
An acoustic subwoofer like DW’s woofer drum does (by extending the size of the kick, or sometimes the diameter too).
When using SK with a smaller drum (say 18”) it doesn’t suddenly give you extra lows as if you would play a 24”.
So it is certainly depending on the actual size it is used for as different sizes give different frequw cirs (and thus audible sounds).
Otherwise we would all just play one easy to go size for our bass drums.
That is why Yamaha calls their SK a sub frequency capturing device.
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