AA 1A Amplifier

After 12 years of design, projects and manufactured audio units, after we introduced our Reference Anniversary Line, was our intention and goal, to build up an entry line of products, a Headphone Amplifier/Line Preamplifier and a Power Amplifier. On its way is also a Multi Media Center.

As our goal was also to introduce very affordable audio preamplifiers/amplifiers series (but without any major compromises) the decision was not easy. So we developed amplifier approach to follow our commitment to provide natural, pleasing reproduction systems. The power amplifier is without crossover distortion even though it is not working in Class A. We are proud that, even though the series is an entry level and affordable, it follows Audio Alto concept. AA 1A is a compact power amplifier that provides up to 2x 125W into 4 Ohms load or in bridge mode 250W into 4/8 Ohm load.

Highlights

AA 1A power amplifier provides single ended RCA and balanced input. Single ended RCA input is differential processed so the source is not connected to common ground. Because of this solution there are no ground loops among different sources. In this way the usual noises are eliminated.
The design of the power amplifier uses N-Core technology from Hypex. Major distinguishing features are flat frequency response irrespective of load impedance, nearly frequency independent distortion behavior and very low radiated and conducted EMI.
Output impedance is very low at 0,01 Ohm and because of this the frequency response is very flat at all loads.
Very high efficiency at 92%.

The mains power switching supply providing the power to the amplifier is a compact, high power, highly efficient, regulated half bridge converter with synchronous rectification on the main output rails.
The efficiency is high at 90%.
The main supply voltage is from 90V up to 250V AC 50/60 Hz (auto switching).
The control unit controls provides the standby mode (consumption 0,12W), monitors the amplifier temperature and potential output voltage error so no protection relays are used. Because of this concept the output has less distortions and the output impedance is very low. The control unit drives also the power clip indicator and the error indicator.

Inputs
1x balanced @ 90 K Ohm
1x differential @ 90 K Ohm
Output
two pairs 4mm binding posts
Gain / Sensitivity
25,5 dB / 1,17 Vrms @ 4 Ohms; 1,29 Vrms @ 8 Ohm
Output power
Stereo mode (2 channels): 75W @ 8 Ohm, 125W @ 4 Ohm, 115W @ 2 Ohm
Bridge mode (1 channel): 250W @ 8 Ohm, 200W @ 4 Ohm

Frequency response
10 Hz — 50 kHz + 0/- 3 dB @ All loads
Distortion
Less than 0,0024 %
Dimensions
348 x 220 x 50 mm
Weight
2,3 Kg
Finish
Satin Natural/Black anodized aluminum, Stainless Steel