I do not know anything about acoustics, or anything like that but I was wondering...

In most when people are producing they have their speakers arranged sort of in front of them but spread out a bit. Is this the way stereo is supposed to be heard?

Is it uncommon for someone to have their speakers, positioned directly to the side of them (where extending their arms in a T shape would cause them to touch each of their speakers.) I assume it would be more similar to the way headphones sound? Is it a bad idea to work like this?

If you take the time to download THIS Alesis M1 Active MkII manual and head over to page10,
it'll approximately show you how to best place monitors.

The last part of your post is more common in DJ Booths where
they have the monitors on either side of the DJ. Not always, but often.

Headphones work different. Don't know exactly, but with HP's
one ear doesn't pick up sound meant for the other and vice versa.
While when using monitors/speakers both ears will pick up left and right.

- farris

farris in completely right.
This is why they need to be somewhat in front of you so that there is less of a phase difference when the sound from one speaker arrives at one ear and then at the other. At around 1600-1700 Hz, the soundwaves are about as long as the width of you head (no pun). This means that sound from for the monitor placed directly abeam you off to the side is completely out of phase from one ear to the other at half that frequency and many other frequencies. You dont want that.

it's not just about what reaches the ears. In headphones, the sound from the right speaker never "meets" the sound from the left speaker. If you put 2 speakers directly opposite each other you will get substantial phase problems, when the sound waves "clash" together so to say.

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