See "4.4. Listening Tests" of the research the technology is based on https://acris.aalto.fi/ws/portalfiles/portal/41964332/Real_time_guitar_amplifier_emulatio

See "4.4. Listening Tests" of the research the technology is based on https://acris.aalto.fi/ws/portalfiles/portal/41964332/Real_time_guitar_amplifier_emulation.pdf https://acris.aalto.fi/ws/portalfiles/portal/41964332/Real_t... those are MUSHRA tests, meaning only skilled listeners are allowed to participate https://en.wikipedia.org/wiki/MUSHRA https://en.wikipedia.org/wiki/MUSHRA