Pioneer A-858

Short description

Amplifier derived from the A-757 (and thus from the A-717) with even larger transformers and even more power in an oversized cabinet, successor of the A-88X, very similar to the analog section of the A-90D/A-91D. However, only introduced at the same time as the A-757 and A-656, therefore smaller knobs already made of plastic and plugged instead of screwed.

Data

General

• Manufacturer: Pioneer
• Model: A-858
• Type: Integrated amplifier
• Years of manufacture: 1989 - 1991
• Made in: Japan
• Color: Black
• Power consumption: 1000W (max)
• Dimensions: 420 x 172 x 474 mm (WxHxD)
• Weight: 24,5 kg
• Original price approx.: 1'500 DM

Connections

• Number of inputs: 8
  • Phono
  • Tuner

CD/DVD

• • Line/Aux
  • Tape-1/DAT
  • Tape-2
  • Tape-3
  • Adaptor In-Out / Pre-Out

Number of outputs:

• • list the outputs here (with level/impedance).

Technical Data

• Continuous power (with distortion factor)
  • 8 Ohm: 2 x 105 W / 0,03%
  • 4 Ohm: 2 x 160 W / 0,05%
• Dynamic power
  • 4 Ohm: 2 x 230 W
  • 2 Ohm: 2 x 350 W
• Total harmonic distortion: 0.03%
• Attenuation factor 1kHz/20Hz ~ 20kHz, 8 Ohm: 200/70
• Bandwidth power 0,05%, 8 Ohm: 5 - 60.000 Hz
• Signal-to-noise ratio phono MM: 74dB
• Signal-to-noise ratio CD, Tuner, Line, Tape: 92dB
• Stereo channel separation:
• Tone control:
  • Bass: +-8dB (100Hz)

Treble: +-8dB (10kHz)

• Loudness: Yes, Volume button -40dB position +5dB(100Hz) +3dB(10kHz).
• High Filter:
• Low Filter (Subsonic): Yes, key 17Hz (12db/oct.)
• Mute: Yes, button
• Direct/Line-Straight: Yes

Special Features

• Elaborate and solid workmanship
• Extremely high output power (immense current stability)
• Adapter loop (through bridge plug on the back)
• Direct switch: for direct connection to the volume control
• Phono switch for MM and MC cartridges + subsonic
• Transformers in solid cast housings to protect against resonance and magnetic interference
• Honeycomb-ribbed chassis and honeycomb-structured heat sink (resonance and vibration damping)
• Robust power supply for stable supply during peak loads
• Spatially separated stages, therefore elimination of mutual interference
• Gold-plated connectors for phono and CD

Remarks

• Previous model:
• Pioneer A-88X

• Successor model:
• Pioneer A-878

• Other models in the same series:
• Pioneer A-227
• Pioneer A-337
• Pioneer A-447
• Pioneer A-656 MK II
• Pioneer A-757 MK II
• Pioneer A-858

Pictures

• [[Image: Pioneer A-858