Technical Audio Devices Laboratories, Inc., today announced the TAD-M2500TX two-channel power amplifier as the newest addition to its Evolution Series of hi-fi audio components.

The TAD-M2500TX power amplifier boasts a completely redesigned circuit layout, upgraded power transformers, and a redesigned machined aluminum chassis, and provides 550 watts of power per channel at 4 ohms. When connected to TAD speakers in the Evolution Series, the M2500TX delivers powerful sound with exceptional clarity, for which every TAD hi-fi component is known.

MAIN FEATURES

1) Ultimate symmetry in circuitry and layout

Sources of positive and negative currents that go through a speaker unit’s voice coils must be identical to drive its diaphragm with utmost precision. To that end, the TAD-M2500TX employs a BTL (bridge-tied load) design that connects two separate amplifiers in a balanced configuration for the left and right channels in the amplification circuit from input through output stages. In this design, positive and negative power supplies maintain perfect symmetry between them, and all power supply circuits are designed separately for each channel. The redesigned machined aluminum chassis has no joints and helps reduce the impedance of the grounding point that serves as a reference point for symmetry. Our meticulous effort to achieve ultimate symmetry between left and right channels and between positive and negative signals did not stop there. We redesigned the grounding point not only electrically but also structurally, and redesigned the circuit and its layout in the first amplification stage.

2) High-capacity transformers with greater purity and efficiency

The TAD-M2500TX is powered by upgraded twin high-capacity toroidal transformers with a power rating of 1 kVA each. To increase the purity of power supply, the internal coil of the transformer is directly connected to the power supply circuit, minimizing the contact points with leading wires. Moreover, terminals for directly connected coils, mounting terminals for motherboards, and clamping screws are all made of oxygen-free copper coated with nonmagnetic materials to eliminate even the slightest magnetic distortions. The shape of the cross-section of the transformer core has been redesigned to circular in the TAD-M2500TX, from square in its predecessor. The circular design improves contact between the core and coils, minimizing unwanted leakage magnetic flux and vibrations. The result is a power supply with greater purity and responsiveness, contributing to the exceptionally accurate driving of speaker diaphragms.

3) Power rating of 550 watts per channel at 4 ohms

The TAD-M2500TX delivers an incredible 550 watts of power per channel at 4 ohms. This is made possible by the simplified Class-D single-output-stage consisting of power MOSFET devices with ultra-low on-resistance in leadless packages that boast minimum power losses and high-speed responses. Combined with a machined aluminum chassis with superb heat dissipation, the result is powerful yet responsive and agile sound reproduction.

4) Meticulous vibration-control design

TAD-M2500TX’s chassis is machined from a 90 kg solid block of aluminum. Its heavy and joint-free design eliminates an adverse effect of external vibrations and helps stabilize the ground potential and music signals delivered to speakers. The immense body of the TAD-M2500TX is supported by a three-point support structure with internally inverted spikes, which physically isolates its chassis from external vibrations traveling through the floor. The minimum contact with the surface on which the TAD-M2500TX sits keeps external vibrations from traveling through the feet and adversely affecting circuits and parts inside the case. This elaborate vibration-control design results in more condensed and energetic audio reproduction with spatial nuance of the music retained intact. Heavy-duty, extra-large speaker terminals on the rear panel, similar to the ones found in the Reference Series power amplifiers, reduce mechanical and electrical stress on connected speaker cables to improve their stability and bring out the best of them.

5) Bi-amping option

The TAD-M2500TX offers a bi-amping option for compatible speakers. With this option, one TAD-M2500TX can be connected to the tweeter terminals of right and left speakers, and another to their woofer terminals. The bi-amping connection eliminates interference between speaker units and improves their separation. This option brings out the best of amplifiers and speakers, enabling them to deliver sound with exceptional clarity.

TAD-M2500TX specifications

Power Output 550 W at 1 kHz, 4Ω
Rated Distortion Less than 0.05% at 1 kHz, 275 W, 4Ω
Signal-to-Noise Ratio 112 dB or higher
Frequency Response 10 Hz to 50 kHz, +0 dB/-3 dB
Gain 29.5 dB
Input Terminal
(Sensitivity/Impedance) 1.5 V/100 kΩ （balanced input）
0.75 V/50 kΩ （unbalanced input）
Power Requirements AC 120 V, 60 Hz (United States)
AC 220 V to 230 V, 50 Hz/60 Hz (Europe/Asia)
Power Consumption 250 W
Standby Power Consumption 0.5 W
Dimensions 440 mm (W) × 170 mm (H) × 467 mm (D)
Weight 42 kg