I own one... Great basses. As mentioned they were built in Japan... With the bartolini preamp, there is a mid control inside of the control box... never got a clear answer from anyone as to why... but It's a great bass. There is a 6 digit serial number. Not close to the bass right now but the first 2 digits are the month, the second 2 are the year and the last two are the build #. For example, 079218 would be the 18th bass made in July of 92. I could be incorrect in the order, but the number should read similar to that