Ok, I'm being completely serious when I ask this:

What exactly is an amp head?

For example, what purpose do they serve, why they're important, what do they do, etc.

I've been playing guitar for a few years now but I never fully understood the purpose of an amp head, so any help is appreciated, I REALLY want to know. Thanks in advance.
*Puts on flamesuit*
when you look at a half stack. the amp head is the top part.
the amp head is basically the whole amp and your sound although speakers take a role too.(cabs, the bottom part of a stack) Amp heads control your volume gain EQ reverb if it has some and presence( or whatever a company names that knob)
Oh I think I get it now, you would put the amp head on a half stack or an amp that doesn't already have eq settings and such? Most amps already have those settings on them, but the ones that don't need a head?
Quote by Roast Beef
Just try plugging straight into the speaker cabinet, you'll work it out

hahahaha do that

but on a serious not yes. the ones that you said have a cab are called combo amps. all in one basically. half stack 2 different pieces.
an amp head is basically a combo with more wattage and no speakers.
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Basically, an amp head is the preamp and poweramp sections of your amp (where all the big shiny knobs are) in one unit, which are accompanied by a speaker cab, which is basically either 1, 2, 4 or 8 speakers wired in a unique way. Basically, it is the same as a normal amp but cut in two. The original reason this was done was to make transporting easier and to allow for 4 speakers to be separate to an amp to minimise weight for roadies, but it can also allow users to mix and match different cabs and heads from different manufacturers to get different tones, provided the "impedance" matches (that's detailed **** you don't really need atm). That's my simplified version, there is a sticky up the top of this sub-forum that explains EVERTYHING.
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