Advertisers and politicians make decisions based on smaller percentages!I'm guessing amp-owners like to know when their amp was made, if it's old-ish.Subtract one from the other and I'll have a rough-cut figure for how many were made. PRII owners were kind enough to start sending their serial numbers in.
If you've got one of the 14 amp models in this range you can get a rough idea of its date-of-manufacture from these tables.
For the batches labelled "date codes needed", I haven't got any loudspeaker or transformer date codes, or (gold dust) the 4-digit inkstamp on the metal chassis, which is usually only visible when out of the wooden cab.
While it's anyone's guess how many of those 5500 were Champ II and how many were Bassman 20, they seem to come up on e Bay equally often. People keep on referring to this 'fewer than 500' thing, especially when they're trying to sell one as 'rare', but I'm still waiting for anyone to point back to the original 'fact' of the matter!
) If your amp's serial number falls into the last 3 batches then your best hope of dating it is if you've still got the original speaker.
One run of Princeton Reverb II serial numbers seems to stretch from 1984 to 1986 with just a few from 1987, yes 1987, when some 220V models were still being shipped to Sweden and the UK.
So if you'd like a bit more detail on an amp in that category please get me the speaker date codes, not just the serial number. Upon arriving at Fullerton, any one of these chassis might be built as a Champ II or a Bassman 20, in a process which appears semi-random when tracked only by serial number.
For a while I also had automated searches running on e Bay for these 14 amp types - whenever one appeared for sale I would contact the seller, asking for the serial number.
9 out of 10 did - many thanks to them for their trouble and good will.
latest updates; small changes to a few amp batches dates, Nov 2015, Dec 2015, Feb 2016, July 2016, Sep 2016, March 2017, Feb 2018, Mar 2018, Aug 2018, Apr 2019 typos found, two edits, thanks Ben H, June 20 info updated, totals unchanged Oct 2014 really nifty table design Aug 2014 small data and totals updates Jan 2014 (info updatedthe website I developed for this amp's care and feeding, .
Eventually, I thought, I'll get a rough idea what the highest and lowest s/ns were.
These 3 runs of serial numbers start in mid-1984, when production was fairly normal.