If you need to see them, Google the Fender Field Guide. Quite simply, a Silverface Fender Amp is an amplifier made by the Fender Musical Instruments Company from late 1967 to 1983. I suppose that if you compare Silverface equipment to its earlier tweed and blackface brethren, the silverface amps are in many cases not that great, and that is the justification that has been used for a couple of decades by Silverface critics.
They are called "silverface" due to the brushed aluminum look of the faceplate. Do a quick look on ebay, eliminate the ridiculously high opening bids that no one else has bid on, (which in case of the search I just did is well over half of them) and you'll find that in most cases you can expect to pay about twice as much for a Blackface than a Silverface, and at least three or four times as much for a tweed.
(5 or 6 times as much in the case of a tweed Champ vs a silverface one) Face it, tweeds are actually museum artifacts, and if you find any genuine tweed Fender for under a grand, buy it and consider yourself extremely lucky, and I'm not going to compare Silverface equipment to tweed.
Personally, I would rather compare Silverface equipment to what is available today. It is a great sounding little amp, and you can usually pick them up for under 0.
For the next few years, many models received mods to the current circuits, and in some cases totally new circuits.
Probably the biggest change made by CBS was going from a true "bias pot" to a "balance pot" on the class A/B amps. (Unlike many others) I don't profess to know what CBS was doing, why they went the direction they did with the circuits.
I apologize in advance if I got a date wrong, a model wrong, etc.
Its pretty hard to get extremely accurate information on the history of Fender amps..several reasons..someone will always criticize the specifics.
Of course, during this time, rock musicians were seeking more and more distortion.
Both had seen many miles by the time I got them, and I've added a few more to the Bassman in the nearly 20 years that I've owned it.
Actually, when I bought my head, it was in a Blackface box...which confused me for a long time until I realized what had happened.
It is a pretty cool little amp, and I really liked it. I don't think it has been plugged in since..Champ was louder, and sounded MUCH better. I still think it is a great little amp, especially for the price...
I think that Gibson made a mistake discontinuing it..just needed a little improvement) I mentioned that the Champ is hand wired.by Frank Stroupe ***WARNING-There are voltages inside of a tube guitar amp that can KILL you.