Hi, I have just started making hip-hop/ rnb beats on fruity loops but they sound a little plain. Can anyone offer any tips to add more depth and originallity to them?

Have you read the sticky thread "A few tips on how to make your songs sound better"?

Other than applying the techniques discussed in there it's really down to compositional abilities. You may be able to make improvements by utilising more/different chord structures, counter melodies or what-have-you, but I don't know what level of musical knowledge you have or what you're already doing to make specific recommendations at the moment.

Consider reading my tutorials on OverClocked ReMix. They apply to any sequencer, but they have FLP examples.

http://www.ocremix.org/phpBB2/viewtopic.php?t=59249
http://www.ocremix.org/phpBB2/viewtopic.php?t=59423
http://www.ocremix.org/phpBB2/viewtopic.php?t=62065

Nice tips there, zircon_st. I hope to test out some of them later.

One thing I do that makes my drums in a song sound slightly better is to tune them to the key of the song. You have to do it one drum sample at a time and if you can't get it to exactly match, try tuning it to the fifth of the tonic. It's pretty tedious though and will only slightly improve the overall sound.

When it comes to drums you will want as many drum samples as you can get. Mix and match different hits and add effects to them, tweak the pitch, etc. Drum loops are also nice because fruity loops has a drum slicer that will slice the loop up into single hits, but since it was a drum loop to begin with it will have resonating sounds from previous drums or multiple drums played on one hit, which can be rather valuable to get fuller sound or uniqueness.

There's a trick with the layer module in fruity loops, if you have a ton of different samplers with drum samples on them, hook them up to a layer and choose "split children". This will give you the same effect as a sliced beat (which makes it easier to compose an entire drum sequence in one piano roll view instead of going between each sampler).

You can never have too many drum samples.

[edit] if you want to understand how the good drum loops are made, try to recreate them with single drum instruments. You will find a lot very soft and subtle drum hits inbetween, even ones that are off tempo.

[ninja edit] another trick I use, in fruity loops go into options > general and enable legacy effects. Now in the sampler if you scroll down you have more effects, most notably the stereo seperation one. experiment with that as it can add more richness to the drums and usually is more effective than the stereo enhancer effect.