Accuphase A-250, Class-A Monophonic Power Amplifier

Full Description

Overview
Ultra-low-noise design with unprecedented S/N ratio of 127 dB brings out a stunning wealth of detail. Semiconductor MOS-FET switches enable output circuitry without any mechanical contacts. Two pure class, A power units arranged right and left are driven in parallel to deliver 100 watts into 8 ohms with impeccable quality. A damping factor in excess of 1,000 means that speaker control is nothing less than perfect. The massive A-250 represents a new pinnacle in power amplifier history. Encounter music like never before.

Specs
Continuous Average Output Power (20 – 20,000 Hz)
Normal mode:
– 800 watts into 1 ohm ＊1
– 400 watts into 2 ohms
– 200 watts into 4 ohms
– 100 watts into 8 ohms ＊2
Bridged mode (2 units):
– 1,600 watts into 2 ohms ＊1
– 800 watts into 4 ohms
– 400 watts into 8 ohms

Total Harmonic Distortion:
– 0.05% with a 2-ohm load
– 0.03% with a 4 to 16-ohm load

Intermodulation Distortion: 0.01%

Frequency Response:
– At rated continuous average output: 20 – 20,000Hz ＋0 －0.2 dB
– At 1 watt output: 0.5 – 160,000Hz ＋0 －3.0 dB

Gain: 28.0 dB (GAIN selector in MAX position)
Gain Selection: MAX, –3 dB, –6 dB, –12 dB
Output Load Impedance:
– Continuous output: 2 to 16 ohms
– With music signal: 1 to 16 ohms
Damping Factor: 1,000
Input Sensitivity (with 8-ohm load):
– 1.13 V for rated continuous average output
– 0.11 V for 1 watt output

Input Impedance:
– Balanced: 40 kilohms
– Line: 20 kilohms

Signal-to-Noise Ratio:
– 127 dB (GAIN selector in MAX position)
– 133 dB (GAIN selector in –12 dB position)
– At rated continuous average output

Output Level Meter
Digital power meter:
– 5-digit indication showing true power (W)
– Range selection AUTO / 10 W / 100 W / 1,000 W
Bar graph meter:
– Represents output voltage values (dB) using 40 points
Peak hold time:
– 1 second / ∞ (infinite) selectable ＊Display off switch provided
Power Requirements: 120/220/230 V AC, 50/60 Hz
Power Consumption:
– 300 watts idle
– 430 watts in accordance with IEC 60065