[Newbie Q] pcb design question: how much to etch/trace width

[gaussmarkov]

i have been looking at the inside of some of my commercial pedals and i noticed that many pcbs are different from the ones i usually see here in a basic way:  they leave most of the copper on the pcb.  that is, the "traces" are as wide as possible with only small separation tracks etched in.  is this
better?  cheaper?  why don't we do it this way?

thanks in advance.

[R.G.]

This is the so-called "minimum etch" style.

Obviously, it's cheaper on etchant, but that's not why they do it - I don't think. It's good for some logic and RF applications. For audio, there's no particular advantage.

If it's two sided and the traces are on one side while the wide flat places are on the other, this is so-called ground plane design. Again, good for RF, not necessarily an advantage at audio.

Why don't we do it that way?

It's HARD to lay out compact boards that way for the beginner.