Inside the CTA408.
* Driver stage tubes supported by MOSFET circuitry.
* Numerous individual power supplies, designed to operate with constant power, thereby isolating power stage fluctuations from entering the input stages and eliminating reverse modulation towards the AC supply grid.
* Dedicated Class A headphone amplifier, (speaker output mutes on headphone insertion)
* Excellent J-FET- Phono-amplifier. Active RIAA equalization employing more than one hundred discrete components inside a noise-shielding box of its own.
* The output transformers are Copland in-house design, fine-tuned for optimal power bandwidth. The massive core size of the transformers prevents core saturation, and they are able to transfer full power well below 20Hz to the loudspeakers with a minimum of phase shift. Multiple layers of interleaving wires ensures a superb linearity. The extended high frequency performance reduces the requirements for internal lag compensation after the amplifiers 15dB negative feedback loop is closed.
* The amplifier power plant is based on the KT150 power valves. These valves are a new variant of the legendary 6550/KT88 and in the CTA408, they surely demonstrate that the everlasting sound qualities of tubes can be extended into regions nowadays dominated by solid stage designs.