If you have a spare speaker or perhaps an old subwoofer you no longer use, you can convert it to a subkick and get that extra "umpf" when recording a bass-drum.

In case you didn't know, a microphone is basically a speaker and vice versa, and a big membrane is better at detecting low frequencies (plus it's more likely to withstand the air-pressure).

The only problem is that the signal from a speaker is not balanced, and therefor prone to noise, one way to mitigate this is to eq your way out of the problem, after all only the low frequencies are needed, so the 50/60Hz noise (depending on your location) from the mains is the main thing you need to worry about.

Another way is to just use a linedriver placed as close as possible to the sub-kick.

This one I made using an old e-drum:

I used hairbands to make a "floating" speaker-mount, a mesh head on the speakerside, and a dampened normal head on the other side.

I've even seen people using a free-floating speaker with great results, so perhaps it's a bit overkill to use a drum, but it looks nice.