How do I get more 'air' in my recordings, like the pros do?

How do I get more 'air' in my recordings, like the pros do?
Modern popular music recordings seem to have 'air' in their high frequencies. How do you get that? Do you need an oxygen tank?
Source: www.record-producer.com

Do your cymbals sound like trash can lids?
You'll never get a good recording of a drum set if the cymbals sound bad. But how you be sure to get a perfect cymbal sound every time?
Source: www.record-producer.com

Can you connect two loudspeakers to one amplifier channel?
In live sound, it is a common desire to use one amplifier channel to drive more than one loudspeaker, usually for the purpose of distributing the sound more widely. But is this harmful for the amplifier or loudspeaker? And is there are limit to how many loudspeakers can be connected in this way?
Source: www.record-producer.com