DIY sub kick mic, testing 3 woofer sizes

Inspired by some forum posts and videos I decided to try to build a sub kick mic. It's pretty simple, you just need a woofer, a cable and a way to mount the woofer. You can settle for a snare stand or finish it more 'pro' with a casing and a built in connector so you can use regular mic cables. I decided to try the latter. A woofer size of 6 to 8 inches is generally suggested. However, a drum recording handbook mentioned 5 to 6.5 inches. I got my hands on a 5.25", a 6.5" and an 8" woofer and gave them a try. All recordings are straight from the mics, without any EQ or other effects. Be sure to switch to HD and use good headphones or monitors or else you won't hear the sub low frequencies. Edit: I did a test regarding the remark that putting the sub kick further away from the resonant head will build up more low frequencies. I recorded at 3 distances (2, 10 and 20 cm or about 1, 4 and 8 inches) and normalized the levels to make up for volume levels. Then I listened and also checked with a frequency analyzer. My conclusion: there are no (or very small) differences in low frequencies but the recordings had a different character in the higher frequencies. This was just my test, maybe your results are different.