"Legacy" is both a blessing and a curse. It doesn't matter whether legacy is 1 year old or 40. If it defines the expectations for a product, then every subsequent product has to meet the same expectations. To meet those expectations, new products have to either be identical to the old ones, or credibly behave the same way.
If they do those things, then they have a market niche that nobody else can fill. Anybody else who claims to re-create the legacy sound will constantly be on the defensive about it.
If they don't, then they give up that niche and have to take their chances in the broader market that doesn't recognize their brand as special.
Given those things, sticking with a legacy sound actually seems like a pretty good idea. And if Yamaha wants to innovate and take their chances in the broader market, they don't have to mess with the Ampeg brand. You can see this all over the place, when a company wants to enter a new market segment, they come out with a new brand, or at least a new "series" within a brand.
The car makers have struggled with the same problem. During the oil crisis, Cadillac had to convince the public that a K car with a Cadillac badge is still a Cadillac. Today, during an oil glut, BMW has to convince the public that a gigantic SUV is still a BMW.
If they do those things, then they have a market niche that nobody else can fill. Anybody else who claims to re-create the legacy sound will constantly be on the defensive about it.
If they don't, then they give up that niche and have to take their chances in the broader market that doesn't recognize their brand as special.
Given those things, sticking with a legacy sound actually seems like a pretty good idea. And if Yamaha wants to innovate and take their chances in the broader market, they don't have to mess with the Ampeg brand. You can see this all over the place, when a company wants to enter a new market segment, they come out with a new brand, or at least a new "series" within a brand.
The car makers have struggled with the same problem. During the oil crisis, Cadillac had to convince the public that a K car with a Cadillac badge is still a Cadillac. Today, during an oil glut, BMW has to convince the public that a gigantic SUV is still a BMW.

