Accuphase A-48

Featuring a six-fold parallel push-pull architecture with power MOS-FETs, as well as ideal gain allocation realized with discrete semiconductors in an instrumentation amplifier configuration, the A-48 harnesses a wealth of advanced technology. Its outstanding performance is exemplified by a signal/noise ratio of 117 dB, output of 360 watts into 1 ohm (music signals), and a damping factor of 800. The newly designed output protection circuit can detect any short-circuiting of the speaker terminals, for complete peace of mind. This power amplifier is the ultimate instrument for immersive music appreciation on the highest level.

Power MOS-FETs in 6-parallel push-pull configuration
Linear output characteristics over entire load impedance range
Strong power supply with massive toroidal transformer and large 60,000 uF filtering capacitors
Instrumentation amplifier principle
High-gain signal input section in discrete configuration
Dedicated power supply for signal input section
Polarity switching for balanced input connectors
MCS+ circuit topologys
Current feedback principle in amplification circuitry
Protection circuitry using MOS-FET switches
High damping factor of 800
Speaker output protection circuit guards against short-circuiting
Two sets of large speaker terminals
4-step gain control
Support for bi-amping and bridged mode
Aluminum top plate with hairline finish

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Stereo operation (both channels driven): 360 watts per channel into 1 ohm, 180 watts per channel into 2 ohms, 90 watts per channel into 4 ohms, 45 watts per channel into 8 ohms
Monophonic operation (bridged connection): 720 watts into 2 ohms , 360 watts into 4 ohms, 180 watts into 8 ohms
Total Harmonic Stereo operation (both channels driven)

Distortion: 0.05% with 2 ohm load 0.03% with 4 to 16 ohm load Monophonic operation (bridged connection), 0.03% with 4 to 16 ohm load
Intermodulation Distortion: 0.01%
Frequency Response: at rated output: 20 - 20,000 Hz +0, -0.2 dB, at 1 watt output: 0.5 - 160,000 Hz +0, -3.0 dB
Gain: 28.0 dB (with GAIN selector at MAX) (Stereo and monophonic operation)
Gain Selection: MAX, -3 dB, -6 dB, -12 dB

Output Load impedance
Stereo operation: 2 to 16 ohms
Monophonic operation: 4 to 16 ohms
With music signals only, 1-ohm loads are permissible for stereo operation and 2-ohm loads for monophonic operation.
Damping Factor 800
Input Sensitivity (with 8-ohm load, GAIN selector in MAX position): Stereo operation: 0.62 V for rated continuous average output (30 W) 0.11 V for 1 watt output, Monophonic operation: 1.23 V for rated continuous average output (120 W) 0.11 V for 1 watt output
Input Impedance: Balanced: 40 kilohms, Line: 20 kilohms
Signal-to-Noise Ratio (A-weighted, input shorted) 112 dB (GAIN selector at MAX), 122 dB (GAIN selector at -12 dB) at rated continuous average output

Output Level Meters
-8 dB to +3 dB (indication in dB and %)
Operation selector: OFF / NORMAL / HOLD (
Holdtime: 8
Monophonic operation: same value displayed for left/right
Power Requirements: AC 120 V/230 V, 50/60 Hz (Voltage as indicated on rear panel)
Power Consumption: 180 watts idle, 427 watts in accordance with IEC 60065
Maximum Dimensions: Width 465 mm, Height 211 mm, Depth 464 mm
Mass: 33 kg