when people are making statements comments about amps and they say something involving "the front end of the amp" what exactly are they talking about?
Not really. Just listen to it. If you like what you hear it's good. Your amp will tell you if you’re doing something wrong.

The front end or pre-amp section are the small tubes in your amp. They take the little signal from your guitar and amplify it enough to drive the power tubes (the big ones). Second, the front end has a major impact on your tone as the tone controls are located in this section.
Usually if you're talking about plugging into the front end it means the input on the front.
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