Mentioned in this TalkBass.com forum. > I have a fretless Wal bass that was made in 2000 for Midge Ure, a singer, becasue he wanted to get as close to Mick Karn's sound as possible, Midge and Mick had collaborated in the past...turned out Midge wasnt much of a player > > it also happened to be one of the very few Wals witha Mrk II body and Mrk III neck joint, probably the best overall design they ever did. > > not really vintage but a good story none the less [The bass is also featured in the Wal Database](http://www4.cs.fau.de/~koesters/Privat/Wal/), which lists a serial number of W20700 (dating it July 20, 2000) and offers three pictures. > lined-fretless Ebony (4 strings, 24 frets) > Walnut Facings The bass can be seen [here](http://www4.cs.fau.de/~koesters/Privat/Wal/walpics/W20700.jpg), [here](http://www4.cs.fau.de/~koesters/Privat/Wal/walpics/W20700-back.jpg) and [here](http://www4.cs.fau.de/~koesters/Privat/Wal/walpics/W20700-front.jpg).more
There is very little difference in tonal qualities for the Wal basses. They all feature the same circuitry that gives them their signature growl. The differences actually lay in the appearances between the MK 1, 2, and 3 bodies.
The MK 1 features short, stubby horns and a flat back end. They closely resemble a Fender Precision bass that has been squished bridge to neck.
The MK 2 features a much longer top horn but is generally the same shape as a 1.
The MK 3 features the longer horn of the MK 2 but also adds in a slanted back end behind the bridge, running from the strap peg inward and upward towards the players chest.