Not only that, but also their many variations, such as the 55hz “bass” cones and etc. The bottom line is: be careful when using the name “Greenback”.
G12M Early 20w G12M 25w 75hz Celestion first introduced the G12M (medium 35oz ceramic magnet) around 1965 with a power handling of 20w, with options of 8ohms or 15ohms and a resonance frequency of 55hz (bass cone) or 75hz (lead cone).
This is also why the G12H has a certain “bright” character, since the mid frequencies won’t mud it out. The big magnet provides a very strong attack and aggressive sound.
I’d say even “percussive”, depending on the situation.
Because of this, it’s also considered a bit cold and stiff by a few players.
On the other hand, due to the higher power handling, it won’t compress as much as the G12M when pushed and will sound more “open”.
The G12M speakers were mostly found in the old Marshall 1960A and 1960B cabs.
It can be a bit confusing – the labels are even more unreliable in this transitional period, so you have to be careful).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.It’s simply a “generic” name that was given to the speakers of this period, similar to how “Plexi” is a name to all the pre-1969 Marshalls.In other words, both the G12M and G12H can be called “Greenbacks”.During the late 60s, they had a “100” logo on the upper corner, indicating that the cab was loaded with the heavy-duty 25w speakers (remember that early G12M had only 20w and the G12H speakers had 25w instead – thus making the 1982 the first 100w cab).Just before the 70s, the “100” logo was dropped (the cab was now rated at 120w, since the G12H was powered up to 30w sometime around April 1968 – you can still find the “100” logo on cabs made up to 1969) and so, since they also had the same measures as the 1960 model cabs, it’s almost impossible to tell them apart without further inspection (just like the 1935 cabs).Around 1968, the G12M became a 25w speaker and the label of the 15ohm version also changed to 16ohm at some point.G12M Blackback 25w 55hz The sound of the G12M tends to be very pronounced on the midrange, with a sweet, woody, warm and smooth sound.Speakers are extremely important when we are talking about tone. This article will be a (maybe not so) small post about the history of Celestion, as well as a brief description of each model they produced over the years. I’ll simply feature the ones that I think are the most popular and most widely used models. Early years and the G12 Al Ni Co Celestion started as a manufacturer of speakers for general use (radio, TV, etc.) back in the 1920s.They give the amp its “voice” and so, in order to get the right sound, you will need to use the right speaker. In 1947, it was bought by British Rola and, one year later, production moved to Thames Ditton.