[quote name='Clarky72' timestamp='1385139388' post='2284952']
What sort of weight is the SM400, is it a light amp?
[/quote]
18lb, that's just a shade over 8kg to you or I. Not exactly [i]light[/i], but it won't give you an Ampeg-hernia™ either.
If you're anywhere near me you're welcome to come and have a play.