From Line6:

The powerful combination of reconfigurable analog components and HD modeling allows the DT25 to be four amps in one, capable of producing American cleans, British crunch, class A chime and modern high-gain. Selectable operating class, power tube mode and four Voicings (which offer the perfect combinations of negative feedback loop topology, and HD preamp and tone stack modeling) can dial in classic vintage tones or be shaped into highly customized originals – and each one drips with boutique tone and touch-response.