No matter how well the distortion voicing and EQ is tweaked, these units lack power tube dynamics, and the designers should add a low-watt power tube to recover those dynamics, which are the most important, distinctive component of tube amp Tone. Some people claim some of these units do have squashy power-tube-like saturation. The attempt to emulate amps has *not* led to headphone-level power-tube squash. However, it *has* led to a great awareness, familiarity with the tone of the goal. They *have* laid tremendous groundwork as far as the *EQ* tone of these amps, and of the preamp distortion voicing, and indiv cabinet modelling. The modelling *concepts* are certainly massive strides forward. The goal is becoming extremely detailed, and there is consensus about many things, in this realm which no one thought about before. Now, simply add an EL84 and load to these good modelling amps, and *bam*, we will be there!
See the review of the Ampulator, which claims that all the preamps and amp emulators tested sounded far better and more authentic when combined with a power-tube saturation device. ADA Ampulator (12AX7 used as a "power" tube).
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