Усилители мощности стерео — T+A A 3000 HV

The HV series stereo power amplifier A 3000 HV comes from the German maker T+A and can be switched between stereo and mono operation. It is a dual mono design from input to output, with the high voltage supply rails that give the HV range its name, with the A 3100 HV arriving later as its successor.

Key specs that matter

Rated output in stereo is 300 W per channel into 8 ohm and 500 W per channel into 4 ohm. The response extends from 0.5 Hz to 180 kHz, the signal to noise ratio reaches 115 dB and the slew rate is 60 V/us. A switch selects between RCA and XLR inputs, and two sets of speaker terminals per channel allow bi-wiring or a second pair of loudspeakers. A pure Class A mode is provided, and a High Bias Class AB setting unlocks full power, which exceeds 700 W in bridged mono. The US price was USD 22,250.

Engineering and use context

Its supply rests on a 2000 VA toroidal transformer and more than 240,000 uF of reservoir capacitance, with separate circuit boards and supplies for left and right. The complete power circuit, with its output stages and mains supply, sits in its own shielded compartment, and a 10 mm aluminium dividing wall separates the voltage and current amplification stages. The signal passes through a linear broadband differential cascode voltage amplifier, followed by a single ended large signal stage working in Class A. Output stages combine MOSFET drivers with bipolar transistors, and diodes built into the transistors monitor temperature so that thermal tracking keeps the operating point constant. All conductors in the output stages and power supply are laid out with full symmetry to cancel magnetic stray fields and electromagnetic feedback. The speaker terminals are machined from solid brass and plated with rhodium. On the front panel two large meters show output in watts and decibels, alongside status lights and four soft touch buttons for power, speaker selection and display brightness. The US version uses a 20 A IEC-19 mains inlet and needs a 20 A circuit, and the whole unit weighs just under 38 kg.

Pairing

Its chassis shares its basic size with the P 3100 HV preamplifier, so the two stack as a matched HV pre and power combination, and an HV-Link interface ties it into T+A system control. Owners can also bridge a second A 3000 HV into mono giving every loudspeaker a dedicated channel.

Alternatives

The T+A A 3100 HV replaced this model, adding a High Current Mode with up to 75 W of pure Class A in mono and 120,000 uF of filter capacitance.