Producing jungle and drum 'n' bass

If your break is sounding very light there's a few things you can do.

If you MUST keep it sounding "old school" i'd say stick in a bit of a chopped up, but unprocessed original amen or apache underneath.

Also make the kick a bit more bassy and the snare a bit snappier (try layering a recent dnb snare over the top of the existing snare and adding a touch of reverb).

If you want to make it sound more like the new ragga dnb coming out really tidy the drums up - drop the bass out the current break and whack up the
hi-end a bit then get a nice punchy rock kick and put a 909 behind it without the initial 'thump', just the tail end of it. Change the snare as already described, and also put a tiny bit of low volume echo on it to create 'ghost' snares, and also add some closed hats between the kick and the snares to 'roll' them into each other.

Here's a few tips on making bass...

As someone already said a pitched down 808/909 makes a great low
sub-bass. There's a much easier way to create one tho - get the your
favourite synth that has a nice bass element to it and filter it right
down to a few notches off the bottom (with the resonance about midway)
and you'll get a great sub-bass rumble off almost anything.

To get a more 'menacing' bass sound (as used in a lot of current techy
dnb)combine the above technique with processed hoovers/juno/jupiter type
screechey synth lines played quite low.

A favourite technique of mine is to use either Absynth, the Muon
Electron, or FL Studio's built in '404' to produce a nice screechy bass
then apply a sonic maximizer to it and drop it thru a guitar amplifier
plug-in (my personal fave being Steinberg's 'Warp') then dropping most
of the hi-end out of it, whacking a filter on it, and use that to get
the hi-end noises in the mix. For a good starting point there's a preset
on Absynth 1 called 'DnB Junkie' that's perfect - whach a tonne of
effects on it and you can't go wrong really.

Iain