Dating celestion speakers names of old dating shows
Most of you probably already know, but it’s worth to clarify this to the “newbies”, alright? ; P) G12M Greenback The old Celestions from the late 60s and early 70s had a green plastic back cover and this is why they were nicknamed “Greenbacks” (no sh*t, Sherlock!), but “Greenback” does not refer to any specific model.So, I’ll emphasis again the fact that it’s not the power handling (watts) that will determine if a speaker is “louder”, but the efficiency (db).The power handling will only tell how much wattage it can take safely without blowing.These first speakers went through quite a few changes (also appearing in different colours like silver, chrome and red – also with different codes) during the early years, but they remained with a low (in today’s standards) 15w (20w in latter versions) power handling and with both 8ohms and 15ohms options. With the 100db sensitivity, it was a very “loud” speaker.It was also bright, lively and had a more restrained bottom end.Also, an important note is: 15ohm to 16ohm does NOT really make a difference, since it’s too small on its own. You can run any 16ohm amp safely through them with no worries.
“Blue”), basically a modified version of the CT3757 radio speaker.
Some manufacturers also attached other letters to the end of the date code to indicate day of the week, work shift, serial number, lot number, etc.
The EIA only specifies manufacturer and year/week code.
In later years, the EIA converted to a 4 digit date code so the year could be easily identified.
There are 2 acceptable methods of displaying the EIA date code, with or without a hyphen between the manufacture code and the year/week code.