Speaker question

Save for active speakers. 300W for an 18″ sub will make it barely move and puts a strain on your top end built-in amp.

Also using lower amp load than recommended (so 4 Ohm instead of 8 Ohm) can cause serious damage to the amp (up to burning it out).

I personally would never work with passive speakers again (as a DJ, sound engineering bigger events and concerts obviously a different story) with the current power and quality of active speakers.

I use a (Mackie HD-Series) 18″ sub with two 12″ tops, total of 2,000W RMS and I usually turn the sub down 3dB. Have no problem playing 150-200 people rooms.

Depends on location. Since I have a closed “booth” I can’t put it under there (have seen DJs stick that bulky thing under their DJ table though, even behind a nice cloth. Did a small afternoon function yesterday and had it to one side with one top on a pole then the other top on the other side of the room on a stand. But you could easily have the sub at any convenient spot in the room and your tops where they need to be.

Bass sound that low is omni-directional, so you can’t hear what direction it is coming from. And those low frequencies bounce very well off walls, so there is really not much to win overthinking the position of your sub.

One tip though: don’t put it in a corner or to close and parallel to a wall. If you have no choice, at least angle it to the back wall. This will help tremendously with something called standing waves which can either increase bass response or diminish it.