If you are using amplification with balanced inputs, especially if a balanced design internally, Atma-Sphere may well be your choice. Single ended equipment can be used very satisfactorily as well, as explained on the Atma-Sphere website.
Atma-Sphere designs with their 20-year rule always in mind: they expect their products to be used for at least 20 years before needing major service (for example, new capacitors). With that in mind, they choose parts and tubes that can reasonably be expected to be available -- or to have appropriate equivalents -- 20 years down the road. Long tube life is expected -- Ralph Karsten estimates at least 10,000 hours from the power tubes and 10-50,000 hours from the input/driver tubes. Atma-Sphere's two-year general warranty also covers the tubes for one full year, not just 90 days as is commonly seen.
Dealer disclosure.
Atma-Sphere designs with their 20-year rule always in mind: they expect their products to be used for at least 20 years before needing major service (for example, new capacitors). With that in mind, they choose parts and tubes that can reasonably be expected to be available -- or to have appropriate equivalents -- 20 years down the road. Long tube life is expected -- Ralph Karsten estimates at least 10,000 hours from the power tubes and 10-50,000 hours from the input/driver tubes. Atma-Sphere's two-year general warranty also covers the tubes for one full year, not just 90 days as is commonly seen.
Dealer disclosure.