the seperation between subs and mains can be quite profound.
so it would depend on how you want to 'tango' or what the subwoofers can handle.
limiters are better than compressors?
depends on how soft the softest audio is.
too soft and it goes unheard, bringing it up will make things more existant.
compressing everything isnt really the best unless the speaker outputs everything better.
not everybody wants to listen to notes that are too close together, and then garbled up by whatever frequency and phase response the speaker has.
if it were me, i would start with a limiter only on the mains.
then decide if the majority of my songs that i usually play have very soft passages.
then i would want another limiter for the soft, no different than the limiter for the loud.. except opposite.
compressing the vocals can really sound stupid.
DJ speakers generally sound stupid anyways.
i have heard subwoofers that try to fool people into thinking they are doing something musical.. simply because you hear a lot of racket coming out of the subwoofer box.
kinda like running across the room to dive into a coca-cola and finding out it is pepsi.
a shock with a different 'meaning' than you expected.
should is not the same as must.
if you havent blown a subwoofer yet, maybe you dont need it.
you could try to check the output voltages of your amplifier to see if the bursts are anywhere close to the danger limit.
and you could maybe put a limiter on there (or a compressor) to try and raise the volume.
a compressor can over-work a voice coil and make it run hotter.
i have also heard stories of too much musicality from the subwoofer can cause it to detonate into heat and kill the coil.
there is a lot of design aspects going on.
and i really dont know if it is better to use an equalizer to flatten out the sound, or use a compressor to flatten out the sound.
obviously, they are supposed to work as a team.
consequences can happen when you choose the wrong team.
we live in a trial and error world, and people arent always forgiving enough to share their problems with other people.
simply because another person said they blew the same speaker model that you have.. if you werent there, you really dont know what the compressor was doing.
your compressor could be different, to say that it is more healthy or less healthy.
and sometimes i would assume it is the same right?
if you do try a compressor or limiter.. i would say, at the very least.. listen for distortion and try to check your heat levels.
maybe you can get a decent reading from the dust cap.. or from the side of the speaker.
maybe from the air inside the box.
i dont know how your subwoofer is in the box, and i dont know if reading the heat through a dustcap is enough to catch a thermal problem before it destroys something.
what doesnt destroy the speaker (or the amplifier) then leads to the question, does it sound any better?
people have different tastes, they might enjoy a subwoofer flopping around.. spinning and twirling without doing much else.
and some other people would rather listen to the soft mud that many subs put out.
maybe you are lucky enough to rise above both of them.
safety should come from heat checking and listening for distortion.
if you pass those two tests, it should be safe to play around with the results to see if you can make yourself happier.
ask the crowd which one they like better.
dont make the mistake of asking only two or three people.
maybe dont make the mistake of asking the crowd on the microphone?
i would probably ask on the microphone and suffer any consequences.
if you had an equalizer, you wouldnt have to put yourself in the situation of what is right and what is wrong.
your results would be on the screen.
as long as the microphone is accurate, there shouldnt be any problem.