I use these power amplifiers and integrated amplifier as part of my Hi-Fi / home cinema system and all I can say is they sound fantastic now. The 3 A3 CR power amplifiers and A3 Integrated amplifier are just so much more clear and detailed from the bass to the mid range / high frequencies. John is also always willing to help in whatever way he can. I highly recommend the upgrade service as it will transform your equipment so it sounds far better than when it was new in my opinion.
Adrian Thomas