Headphones vs Amp

I know nothing about equipment so I'd like to know if I can just buy some sort of speakers for my fx machine rather than going into my amp.

The reason I ask is that when I put my headphones in my fx machine it sounds sooo hot but when I put my amp on it changes the sound for the worse even though I put it on the clean channel on low volume.

Btw, it's a Boss GT3 and a Marshall VS30R.

Stereo effects heard through headphones are kinda intense! And a guitar amp is not meant to reproduce the input signal accurately. A guitar amp is another effect on it's own.

You can run your effects output direct to the sound board, and have a signal returned to your own monitor, or you can use a clean transistor amp to drive your monitor from the effects unit.

I don't have those things I'm only a beginner. All I have is my guitar, fx machine and amp.

You could get some powered near-field monitors like you'd use in a project studio.

http://kronosonic.com

If it sounds good through headphones, it should sound good through your stereo system too. Just watch the volume.
All I ever use is my multi effects pedal through a Denon amp out to Polk speakers.
On the effects pedal you need an amp simulator (or buy one seperately like a Redbox Cabinetulator).

If it sounds good through headphones it should be able to sound good through an amp too. One thing you have to remember, though, is that you cannot use the same patches through your amp that you use through your headphones. They both require different settings, most improtantly, you'll have to turn off any cabinet simulation when sending it through a guitar amp.

I've had a fiddle last couple of days and I guess my skill at tone making is improving too coz I've sorted some good ones now.