Kenwood KA 128 Manual

The Kenwood KA 128 is a high-performance stereo integrated amplifier featuring 80 watts per channel RMS, MM/MC phono input, tone controls, loudness compensation, speaker A/B selection, headphone output, and gold-plated terminals. Designed for audiophile-grade sound reproduction with low distortion and wide frequency response. Below are key sections for safety, features, installation, setup, operation, and troubleshooting.

1. Features at a Glance 2. Installation 3. First-Time Setup 4. Specifications 5. Controls and Settings 6. Connecting Devices 7. Operation Guide 8. Maintenance 9. Regulatory Information 10. Troubleshooting

Features at a Glance

Key components: High-power amplifier section, MM/MC phono stage, tone control circuitry, speaker protection system, gold-plated input/output terminals.

Feature	Description
Power Output	80W + 80W (8Ω, RMS, 20Hz-20kHz)
Phono Input	MM/MC switchable with loading options
Tone Controls	Bass ±10dB, Treble ±10dB
Loudness Compensation	On/Off switch for low-volume listening
Speaker Selection	A/B/A+B speaker outputs
Headphone Output	Standard 6.3mm jack
Inputs	Phono, CD, Tuner, Aux, Tape 1, Tape 2
Outputs	Speaker A/B, Tape Rec, Pre Out
Power Consumption	240W maximum
Dimensions	434 x 150 x 380mm (W x H x D)

Installation

Unpack and inspect contents. Place on stable, level surface with adequate ventilation.

Connect speakers: Use high-quality speaker cable to Speaker A/B terminals.
Connect source components: Use RCA cables to appropriate inputs (Phono, CD, etc.).
Connect power cord: Plug into AC power outlet.
Connect antenna: For tuner operation, connect FM/AM antennas.

WARNING! Ensure proper ventilation; do not block ventilation slots. Use correct speaker impedance (4-16Ω).

First-Time Setup

Power on amplifier; allow 30 seconds for stabilization.

Select input source: Turn INPUT SELECTOR to desired source (Phono, CD, etc.).
Adjust volume: Start with volume at minimum, gradually increase.
Set tone controls: Begin with flat position (12 o'clock).
Select speakers: Choose A, B, or A+B using SPEAKER selector.
Phono setup: Set PHONO selector to MM or MC depending on cartridge.

CAUTION! Always turn volume to minimum before powering on/off to prevent speaker damage.

Specifications

Power Output: 80W + 80W (8Ω, 20Hz-20kHz, 0.08% THD)
Frequency Response: 5Hz-100kHz (+0/-3dB)
Total Harmonic Distortion: 0.08% (20Hz-20kHz, 8Ω)
Input Sensitivity: Phono MM 2.5mV, Phono MC 0.2mV, Line 150mV
Signal-to-Noise Ratio: Phono MM 80dB, Line 100dB
Tone Control Range: Bass ±10dB (100Hz), Treble ±10dB (10kHz)
Power Requirements: AC 120V/230V, 50/60Hz
Weight: 12.5kg
Accessories: Remote control, batteries, owner's manual

Controls and Settings

Front Panel: POWER switch, INPUT SELECTOR, VOLUME, BALANCE, BASS, TREBLE, LOUDNESS, SPEAKER A/B, PHONO MM/MC.

Rear Panel: AC inlet, Phono/Line inputs, Tape loops, Pre Out, Speaker terminals, FM/AM antenna inputs.

Input Selection: Phono, CD, Tuner, Aux, Tape 1, Tape 2. Tone Controls: Independent bass and treble with defeat option. Loudness: Compensates for Fletcher-Munson curves at low volumes. Balance: Adjusts left/right channel balance. Speaker Selection: A, B, or A+B outputs.

Connecting Devices

Phono: Connect turntable to PHONO inputs (set MM/MC accordingly). Line Level: CD player, tuner, etc. to respective inputs. Tape: Tape deck to TAPE 1/2 for recording/playback.

Turn off amplifier before making connections.
Use high-quality interconnects for best performance.
Ensure proper grounding for phono connections.
Match cable colors (red-right, white-left).

Tip: Keep signal cables away from power cords to minimize interference.

Operation Guide

Daily operation procedures for optimal performance.

Power sequence: Turn on source components first, then amplifier.
Volume control: Start low, increase gradually to desired level.
Source selection: Use INPUT SELECTOR for different components.
Tone adjustment: Use BASS/TREBLE controls to suit room acoustics.
Loudness: Engage for low-volume listening to restore bass response.
Speaker selection: Choose A, B, or both for multiple speaker pairs.
Headphone use: Automatically mutes speaker outputs when plugged in.

WARNING! Do not operate with covers removed. Avoid extreme volume levels that cause distortion.

Maintenance

Unplug before cleaning. Use soft, dry cloth for exterior. Clean controls with contact cleaner if noisy.

CAUTION! Do not use solvents or abrasive cleaners. Keep away from moisture and extreme temperatures.

Regulatory Information

FCC Part 15: Class B digital device; complies with interference limits for residential use. Copyright © Kenwood Corporation. All trademarks property of their respective owners. For technical support, visit www.kenwood.com or contact authorized service centers.

Troubleshooting

Symptom	Possible Cause	Corrective Action
No sound	Volume/mute/speakers	Check volume setting, speaker connections, speaker selector
Distorted sound	Overload/connections	Reduce volume, check source component, verify cables
Hum or noise	Grounding/cables	Check phono grounding, separate signal/power cables
One channel dead	Balance/cables	Adjust balance control, check interconnects, swap cables
Protection circuit active	Short circuit/overheat	Check speaker wires for shorts, ensure proper ventilation

Reset: Power cycle amplifier. If issues persist, consult service center.

Service: Authorized Kenwood service centers only. Do not attempt internal repairs.