Most musicians know what they mean when they speak about an amplifier's Tone. But this term, Tone, is quite a complex thing to communicate.
For improved communication I shall refer to the term of Character to refer to the Harmonic Content related components of an amplifier's response, and Tone to refer to the Frequency Response characteristics (as in "tone controls"). Since the Character of the sounds is strongly related to the Gain stages within the amplifier I will group these together as Gain & Character. So toward that, let's define these terms a little more broadly as below.
Gain & Character — The tonal characteristics related to the distortion components in the sound, wholly or in part due to the gain stage construction and line-up within the amplifier. Typical terms used to describe the Gain and Character of an Amp might be: Clean, Crunch, Bluesy, Overdriven, etc...
Tone — The tonal characteristics related to the frequency response of the amplifier, and usually adjusted with tone controls and related circuitry. Typical terms used in referring to the Tone of an Amp might be: Low Bass, Warm, Scooped/Mid-Boost, Bright, Presence, etc...
Features are the next most important aspect of your amplifiers usability. In the Mods section there is also a section dedicated to discussing the many possible features that can be added to your amp. Features might include Effects Loops, Standby Switches, additional outputs, etc...
Browse through the pages of Mods for ideas for improving your amplifiers tone, character, and usability. The Repairs pages offer some insights and information regarding having repair work done at Williams Vintage Amps, and the Tech pages provide some background information and links regarding Tube Amplifiers.
Visit the About for more information about Williams Vintage Amps.