SwampDonkey":23bhc2lg said:
I have heard differently. I've seen a few different people say they prefer the tone of the older (pre-external bias) models to the new ones.
I don't know if there are any tonal differences, but differences in tubes and bias settings will make a difference. In other words... If you want to compare an old and a new Herbert I guess you'd have to install the exact same tubes and bias them identically before you can decide that the amp itself sounds different from the other...