The mbl 101E represents many significant changes over the 101D. The low bass driver is manufactured to be 30% lighter, and is significantly faster than the one in the D version, allowing it to move more air and to keep up with the radial drivers much better. The lower cabinet volume has been increased and the port diameter has been increased, allowing the low bass driver to float more freely and quickly, and forever eliminating the "port noise" that could be heard on the D version at high SPLs with dynamic music. This also allows more bass energy to enter the room, completing the full presentation of all the radial drivers.
There have also been quality upgrades in the manufacturing process of the radial tweeter, and several updates to the crossover of the entire system.
I've spent much time working demos at CES for mbl and was always in love with the 101D. After the first track at this past CES 2004, where the 101E was first shown, the speaker was totally coherent with nothing missing. The D always lacked in the low bass weight and speed. These problems have vanished in the haze. It is truly an amazing loudspeaker, and for the price/footprint, the mbl 101E is the best all around speaker money can buy, especially if you want "to share the music you love with the ones you love." You are not confined to a small sweet spot as with most other speakers. Tonal balance is the same around the room. Walk around. Read. Work. Dance. Live your life. The images are stable and the music is in the room. Not the speaker cabinet.
The 111E has been further redesigned since the prototype shown at the CES 2004. It will make it's debut at the HEE show in New York in May. Check it out.