Roland serial number dating
under controlled atmosphere conditions" Oh and all JC users are welcome to join the facebook group I created for the Jazz Chorus! I found this out about JC120 date formats: From: Someone with a 258xxx amplifier asked when theirs was built and this was the response: "How you would read a typical date code is as follows... " This makes me consider my own amplifier might be as much as half a decade older than it really was: My serial is 715029: Let's break this down: Part 715 Year 1980 (! That number is only 830 difference from the 1976 model listed above (308638 = 1976, 38th week). I'm seeing some discrepancies in the early serial numbers.
If it is, say 308638, then the 308 is the part number, the 6 is the year within the given decade and the 38 is the week of the year. ) (wow, it sat in that store for SIX years unsold but brand new! That 2 may reflect "second year of production" since they first were created in 1975. There's a long thread at HC in the effects forum about JC120 dating and apparently both Roland US and Roland Japan say (according to a poster there) the 1970s serials are not very good for determine date of manufacture although the forumula works for the 80s amps on.
I did a quick bit of experimentation with the Type II (1981 - 1989) 6-number format, it looks like the first number is the year and the second number is the month?
But the year doesn't always run from January to December, for some years it's from May to February or September to June etc.
For some reason, I thought it was newer than that, but now I know.
It's an older model, no effects loop, lovely flicky switches for the power and chorus section, none of this push button or rocker switch malarky. It's been well used and gigged, the exterior has some marks and the knobs all need replacing as they're well worn but it somehow gives it character. The first thing I played on it was 'The Queen is Dead', a bit of onboard chorus and reverb, a 335 and a Tim overdrive and it was gorgeous.
I've seen some inconsistencies in that too, there was someone over at harmony central with an amp older than mine, 636208 that had "2" as the manufacturing date which wouldn't make sense since they first made them in 1975 and "2" would have reflected 1972. That amplifier HAD to be produced prior to 1980 since mine in 1929, but when I can't say. My reverb unit says:" Manufactured by beautiful girls in Milton, Wis.the serial number is not the 2 letters and 5 numbers that Roland expect it to be it is in fact 278XXX, all numbers. I'm trying to figure out the date of my JC-120 too.. Also I am trying to find info on replacement pots as they are all very raspy and noisy.My reverb unit says:" Manufactured by beautiful girls in Milton, Wis.The way it works is the first 2 digits in the Roland SN are the month since November 1980 which was 00, so 01xxxx is December 1980, 02xxx is January 1981, etc...I think you can also go backwards from there for older gear so that 99xxxx is October 1980.