Kenwood KA-80

Data[edit]

General

  • Manufacturer: Kenwood
  • Model: KA-80
  • Type: Integrated amplifier
  • Years of manufacture: 1980 - 1986
  • Made in: Japan
  • Color: Silver, Black
  • Remote control: no
  • Power consumption: 350 watts
  • Dimensions: 440 x 78 x 330 mm (WxHxD)
  • Weight: 7.9 kg
  • Original price approx.: 598 DM


Connections

  • Number of inputs: 4 + 1

Phono MM (2.5 mV / 50 kOhm)

    • Tuner, Aux, Tape Play (150 mV / 50 kOhm)
    • additional microphone
  • Number of outputs:
    • 1 x loudspeaker
    • 1 x headphones
    • Rec-Out 150mV @ 47kOhm


Technical Data

  • Continuous power (at distortion)
    • 8 Ohm: 2x 48 Watt (0,02%)
    • 4 Ohm: 2x 60 Watt (0.7%)
    • brought in tests measured 2 x 65W @ 8Ohm // 2 x 88W at 4Ohm
  • Dynamic power:
    • 8 Ohm:
    • 4 Ohm:
  • Total harmonic distortion:
  • Attenuation factor: > 120 @ 8Ohm
  • Frequency response: DC - 450 kHz

Signal to Noise Ratio: Phono 86 dB / High Level 106 dB

  • Stereo channel separation: > 68dB
  • Tone control: yes
    • Bass: ± 10 dB / 100 Hz
    • Treble: ± 10 dB / 10 kHz
  • Loudness: yes
  • High Filter: No
  • Low Filter (Subsonic): Yes - with activated tone control
  • Mute: no
  • Direct/Line-Straight: yes (DC-coupled)


Special Features

  • Foldable front panel
  • Microphone mixable
  • Low feedback power amplifier circuit
  • Very high slew rate - 150V/µsec.
  • Test winner in many gazettes
  • Reference device in its class
  • Considered as high-end suspicious


Comments[edit]





Pictures[edit]

  • Extract from brochure: Kenwood KA-80

Kenwood KA-80-Prospekt-1.jpg


Reviews[edit]

  • By limiting itself to the essentials, 'spartanly' equipped, so to speak, in current "slim-line" design, this 'small' Kenwood KA-80 makes an appearance. It offers an excellent, discrete MM-phono preamplifier with FET-input, which follows the RIAA-curve with high precision and is distortion-free high driveable. The only OP's are found in the microphone preamp (for karaoke!? = superfluous) and in the tone control stage, which can be switched out of the signal path, resulting in a complete DC signal path! Not often used controls are hidden behind a front panel flap and give the amplifier a simple, elegant appearance. The all-metal construction of the amplifier results in a heavy, stable hi-fi unit.
  • The power amplifier hybrid components (STK60II) of the KA-80 are not quite complete hybrid amplifiers, but contain only pre-driver/driver and power amplifier transistors (plus for optimal thematic coupling further components - diodes and R's) and are unjustly (!) often discriminated against. If you are interested you should have a look at the internal circuit of the STK60II and the environmental circuit chosen by Kenwood: If you know something about circuitry, a 'light' will come on: Everything is serious! At its time, the KA-80 was not exactly cheap (598,--DM), but today it is offered at a very reasonable price. The fact that it is equipped with two mains transformers does not mean a double mono setup, but is due to the flat design. The charge capacity of the power supply electrolytic capacitors is a modest 2 x 7.5mF/50V (too low dielectric strength), and can easily be increased to e.g. 2 x 15mF/63V electrolytic capacitors (35x50mm). There is further room for improvement: The stock power amp working points are set too high. This leads to a (too!) strong heating of the amplifier in idle state. Therefore, the output stage quiescent current should be reduced (by an expert!) by 1/3. This definitely has no effect on the sound, but it does lower the idle operating temperature considerably. Two further electrolytic capacitors (C105/C106) are undersized (25V) and should be replaced by 35V types. The resistors R167/R168 (390Ohm) should be replaced by 470Ohm/R168 and 560Ohm/R167, each at least 3Watt (!).

The 'small' Kenwood works best with 8 Ohm loudspeakers with good efficiency, but can also handle loudspeakers with 4 Ohm nominal impedance; especially if the load capacitors are increased as described above. Speakers with nominal impedances below 4 ohms should be avoided - the KA-80 is not designed for this! In terms of sound, the amplifier, as well as the matching analogue rotary capacitor tuner KT-80, offers absolutely serious, contemporary top hi-fi. Because of its overall characteristics, the KA-80 can absolutely justifiably be suspected of being "high-end". When used with high-quality (!) loudspeakers that are capable of resolving amplifier differences, this amplifier easily plays in the 1st league in terms of sound quality.

PS: A fan must have edited my review here. To call KA-80 & KT-80 1st league is quite an exaggeration. It is styled middle class. In no case more.


Links[edit]

  • Review at Good Old Hifi: [1]