Eminence speaker codes dating
One alternate scheme is: 274 940 274 is the EIA code (RCA) 9 is the last digit of the year (in this case 1949).
Usually single digit date codes are from the 1940's, but have on occasion shown up in later decades, even up to the 1970's.
It is also advisable to add about 6 months to the date to allow for time these parts may have spent in storage.Possible culprits include the preamp tubes, the power tubes, the hum balance resistors, and the power supply caps.I have a 1965 Deluxe Reverb and am trying to figure out if it has a Utah or some other kind of speaker. I also have one of the newer Fender Pro Reverb amps with an effects loop and a silverface Twin Reverb with a volume control. Steve Goldner San Diego Hi Steve, Thanks for your questions. Figuring out which manufacturer’s speaker is in your amp shouldn’t pose a problem unless it’s some aftermarket mystery speaker with no markings.There are other methods used to date "Silverface" amps, you will need to get the date codes from your speaker frame, tube chart or pots.Pots and speakers are usually stamped with a 6 or 7 digit code that can be dated as follows: The first 3 are the manufacturers code 137xxx = CTS 304xxx = Stackpole 140xxx = Clarostat 134xxx = Centralab 381xxx = Bourns 106xxx = Allen-Bradley Speaker Manufacturers codes 67xxx = Eminence 117xxx = Credence 137xxx = CTS 220xxx = Jensen 270xxx = Quam 285xxx = Rola 328xxx = Utah 391xxx = Altec/Lansing 433xxx = Cleveland 465xxx = Oxford 649xxx = EV 1098xxx = Pyle The next number(s) is (are) the year.