Which has more bottom?

[ToneT]

A Double headed, no-hole bass drum
B Bass drum with Kick Port

 

[Andy]

All other things being equal, a bass drum with full reso head will always offer a longer + more full sounding low end "bloom", and typically deliver that audible low end better in an unmic'd gig situation, but may not be the most flexible option when mic'd, either studio or live, depending on the music style.

Which option produces the most / lowest frequencies when subjected to measurement examination, I'm not sure.

 

[johnjssmith]

I'd tend to agree with Andy, if the heads are tuned properly an unported reso head will sound deeper/have a bit more bottom end.

 

[Morrisman]

If you like to bury/sink the beater into the drum, the kickport will let the air pressure escape and make it easier to hold the beater down.
Sound wise, I think the kickport is most effective on smaller kicks, like a 20”. It probably lowers the pitch of 22’s and 24’s, but possibly below the useful/audible frequency range.
So for larger drums, the kickport changes the feel compared to a solid headed drum, rather than the sound.

 

[Bozozoid]

I've heard some full reso bass drums live in my day youngster and they were unbelievable. Earth moving and warm....no comparison.

 

[MusiQmaN]

There is quite a lot in between too.

I use a DW head with the small ports AND a 4” hole, centred and closer to the bottom.

I had a Kickport for a while but it is a heavy item and it didn’t do much extra.

 

[larryace]

Unported for the most bottom ftw...especially for an unmiced bass drum. I like to put one T shirt inside the drum to absorb the most annoying of the bouncy reflections. That is my recipe for an umiced bass drum. With a pretty tight reso head that goes BOING! when thumped, like a tympani. I use a JA, JAW batter head tuning. Just loose enough to make a clean note

 

[dboomer]

If you actually measure frequency, the double headed, no port drum will go lower in frequency. However the ported head will have a bump a bit higher in frequency that will appear to most people as having more low end. Engineers call this “Q”

The way the port works is to cut off some of the extreme low end and add it back in a bit higher where it becomes louder but not lower. Think “lows” vs “thump”.

 

[C.M. Jones]

My bass is always ported. It's a matter of feel more than sound for me. I don't like the response of unported resonant heads. They have minds of their own. I'm intolerant of disobedient bass drums.