Wonderful

You don't own an M3 until you equip the EXB-Radias. I haven't stopped using it since I installed it. Seriously, it's like I can't leave my room. The sounds you can create are immense, and there are 8 'virtual patches' that will generate some very exotic sounds. You can also assign the many physical switches of the M3 to affect the sound. For example, the joystick can be patched to control any destination. This adds a very important level of expression and feel to the sounds you're crafting. If you are worried about the installation, DON'T BE. It's really easy and fun to do (to me anyway). Also, you can assign any of the internal memory banks of the M3 to save all the sounds you come up with, which is really handy. Then you can recall up to 4 of these sounds in the sequencer mode. As you can see, the sonic possibilities grow exponentially. And when you couple this with the M3s ability to sample-in, you've entered an entirely new dimension of production. I haven't had a chance to use the vocoder yet, but I ran some demos that ship with the board and it sounds phenomenal.

Competes the M3

I love this thing! The sounds on the EXB-Radias are awesome and really complement and even complete the M3. Korg's version of Virtual Analog (using their MMT sound engine from the MicroKorg, R3 and Radias) just really sounds good and is very well implemented when integrated within the M3.

The EXB-Radias installs 128 factory programs into internal memory. AND, there are an additional 208 Radias programs and 128 Radias combinations from the website. There are some great Moog, Prophet and Oberheim emulations in the additional programs.

The EXB-Radias has a 16 step modulation sequencer that lets you easily program analog-style arpeggios that can modulate virtually any parameter available in the Radias sound structure (pitch, resonance, filter, panning...) Each program has three of these Modulation sequences which are totally independent from the Karma functionality.

Finally, the vocoder on this kicks. The M3 has a vocoder effect patch, but it doesn't even compare to the clarity and quality of the Radias vocoder. The routing is very flexible and can process both internal and external audio sources.

The EXB-Radias is, for me, the essential expansion for the M3. It rounds out the already great Korg sound set and Korg's interface makes both programming and realtime tweaking right at hand.