What's goin on, dude.
If you're mostly using the MPC as a tap pad for beats, you might wanna look into just grabbing an MPD. If you're honestly looking for another sampler (I've got 3 different samplers at the moment) or a sophisticated sequencer, then which MPC to chose is a matter of the level of needs you have.
The MPC4K has crazy capabilities as far as space, connectivity, and manageability/manipulation of sounds. MPC2K has been around longer and may have fewer bugs. (I've never used a 4K so I can't speak on that) It's a solid sequencer/sampler for a fraction of the cost of the 4K, and the pads will work just as well on either.
What are you looking to use it for? As a drum machine? As a triggering device for drums on your Motif? You trying to record key sequences into it? If it's as a sampler, remember you've already got a sampler on that Motif. Course, the MPC is a nice laid-back sampler with not too many bells and whistles to confuse the **** out of you, and that might be good for you if lots of options is a pain.
Whatever, that's my two cents. I wouldn't blow cash on a 4K personally unless I got signed or had mad projects. Especially when you've got all the sounds on the Motif under your nose.
-tank.
You don't know what I know
Cuz you aint seen through my eyes
This spliff is always lit but it's a natural high
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