VTA305M

About the VTA305M

The Bob Carver VTA305M Black Beauty is a high-power monoblock vacuum-tube amplifier with one line-level input and a 100 kΩ input impedance. Its input stage uses a 12AX7 current-sourced low-noise valve, followed by a 12AT7 long-tailed, high-gain balanced-pair pre-driver stage. The output stage uses six KT120 power tubes in three complementary push-pull pairs, producing 305 watts into 8 ohms, 330 watts into 4 ohms, and 290 watts into 2 ohms. Features include automatic DC restoration using a 6AL5, rear-panel bias adjustment with a front-panel meter, and selectable negative feedback of 20 dB for the classic amplifier sound or 11 dB for the contemporary sound. Specifications include a frequency response of 2 Hz–85 kHz (-3 dB), full-power bandwidth of 24 Hz–28 kHz without filters, distortion below 0.5%, and noise better than 110 dB A-weighted referenced to rated power. The amplifier uses a super-wideband output transformer with interleaved windings and low leakage inductance. It is hand-wired and uses point-to-point construction, with wire-wound and metal-film resistors and metal-polyester capacitors in the audio signal path. The chassis measures approximately 14 inches deep by 12 inches wide by 7.2 inches high and weighs 43 pounds. The standard finish is gloss black with silver fleck and brushed-silver trim; cherry was also available as an option. Speaker terminals are provided for 2-, 4-, and 8-ohm loads.