T+A PA 2000 R

The Integrated Amplifier

Building compact and neat integrated amplifiers with high power output and superb sound quality is an art in which T+A is unrivalled. As proof of this, we present the PA 2000 R integrated amplifier.

It is incredibly dynamic, powerful and incisive. There are two reasons for this: 

the extremely linear output stages with very low negative feedback, which are an entirely new development, and the new form of mains power supply used. We designed the latter specifically for audio equipment to ensure that it is ultra-stable under load, with no risk of collapse, even at extremely high peak levels. The result is that the PA 2000 R can deliver over 200 Watts of continuous power per channel into 4 Ohm speakers, allowing it to drive critical impedance speakers while maintaining effortless control. Sealed gold-contact gas relays are used to switch speakers, inputs and internal signal circuits with total precision and without loss. Separate tone controls are present for each channel, and these and the Loudness function can be completely bypassed. An optional audiophile phono preamplifier module for MM or MC can be simply plugged in. For operation in a surround system, the amplifier can be set to surround pass through mode, selected by a trigger signal.

The two R-Series integrated amplifiers are identical in construction, circuitry, components and sub-assemblies, but differ in output power, connectivity and enclosure size. The input and output sections are equipped with professional plugs (XLR and RCA) made of non-magnetic materials, and all have hard gold-plated contact surfaces. All sockets are permanently screwed to the solid aluminium rear panel.

In the R Series, the volume control and input selection functions are handled by gas-tight gold-contact relays, which are not subject to contact problems caused by corrosion, dust or the effects of aging, even after many years of operation. By integrating the relays directly into the circuit, signal paths from the input sockets to the preamplifier PCBs are kept as short as possible without crosstalk. As an option, input 4 can also be equipped with one of two high-quality phono preamplifier modules with different circuit topologies optimised for MM or MC microphones.

The preamplifiers and power amplifiers of the R series are built according to the dual mono principle. This means that we completely isolate the left and right channels from each other - even in mechanical terms - and use identical circuit boards, so that the sound quality of both channels is identical. The two separate amplifier boards - with input section, volume control, high-voltage amplifier and current amplifier stage - are housed in the right half of the cabinet, where they are protected from the mains supply and output section by a huge heat sink. As with our HV series machines, the input stage circuit topology is based on a cascaded differential amplifier with hand-selected audio J-FET transistors and fully discrete, op-amp-free stages. This overall circuit design, combined with the high quality of the components used, virtually eliminates the need for global negative feedback. The result is that the amplifier has excellent linearity. 

combined with an extremely wide dynamic range. Signals up to 60 Vss can be processed without any distortion. Volume control is provided by discrete precision resistors and gold-contact bistable relays, resulting in absolutely exact channel matching and the shortest possible signal paths, which virtually eliminate noise and distortion. The next stage of the voltage amplifier and the current amplifier are completely galvanically isolated from each other. This uncompromising design completely avoids the risk of feedback effects from the loudspeaker currents in the voltage amplifier stages, and also excludes undesirable effects from the loudspeaker load.

The amplifiers are equipped with separate tone controls for each channel, and the function can be completely disabled by means of gold contact relays. A loudness circuit is present and can be adjusted to match the efficiency of the speakers.