Audio Segment

Kenwood KA-1500

Kenwood KA-1500 is a compact integrated amplifier from the mid-1970s, known for its vintage look and solid performance. Delivering around 30 watts per channel into 8 ohms, it offers a warm, natural sound typical of vintage Kenwood gear. With simple front-panel controls, solid build quality, and a phono stage for turntables, the KA-1500 is a great entry point into classic hi-fi.

1. Kenwood KA-1500 - Front View1. Front View
2. Kenwood KA-1500 - Zoomed2. Zoomed
3. Kenwood KA-1500 - Right View3. Right View
4. Kenwood KA-1500 - Rear View4. Rear View
5. Kenwood KA-1500 - Inside View5. Inside View
6. Kenwood KA-1500 - Inside View6. Inside View
7. Kenwood KA-1500 - Output Transistors7. Output Transistors

General Specifications

Maximum power (8Ω): 30W
Maximum power (4Ω): 36W
Frequency response (±1dB): 20Hz-35kHz
THD (30W): <0.1%
THD (1W): <0.05%
IMD (30W): <0.1%
Signal to noise ratio (Line): 90dB
Signal to noise ratio (MM): 70dB
Input sensitivity (Line): 160mV
Input sensitivity (MM): 2.5mV
Damping factor: 30
Speaker load impedance: 4Ω-16Ω

Dimensions (WHD): 380×140×265mm
Weight: 6.7kg
Produced: 1977
Initial price: 500DM

Measured Values

Maximum power (8Ω): 38W
Frequency response (20Hz-20kHz): <1.0dB
Channel imbalance: <1.0dB
THD (1kHz, 1W): 0.044%
THD+N (1kHz, 1W): 0.044%
THD (1kHz, 20W): 0.037%
THD+N (1kHz, 20W): 0.038%
IMD (70Hz, 5kHz, 1W): 0.063%
Noise: -63.3dB
Amplification: 91.5
DC offset L: -24.0mV
DC offset R: -50.0mV

Maximum Power

Maximum power is measured using 8Ω resistors on both channels. A 1kHz sine wave input signal is applied and gradually increased until higher harmonics rise significantly. Typically, this is the point at which output clipping occurs.

8. Kenwood KA-1500 - Maximum Power - Left Chanel8. Maximum Power - Left Chanel
9. Kenwood KA-1500 - Maximum Power - Right Chanel9. Maximum Power - Right Chanel

Frequency Response

Frequency response is measured using several equilizer settings. 'Flat' indicates the tone controls are either turned off or set to their neutral position. 'Max' and 'Min' refer to the maximum and minimum tone control positions, respectively. In the phono section, the expected response follows the RIAA equalization curve.

10. Kenwood KA-1500 - Flat Equilizer - Left Chanel10. Flat Equilizer - Left Chanel
11. Kenwood KA-1500 - Flat Equilizer - Right Chanel11. Flat Equilizer - Right Chanel
12. Kenwood KA-1500 - Max Equilizer - Left Chanel12. Max Equilizer - Left Chanel
13. Kenwood KA-1500 - Max Equilizer - Right Chanel13. Max Equilizer - Right Chanel
14. Kenwood KA-1500 - Min Equilizer - Left Chanel14. Min Equilizer - Left Chanel
15. Kenwood KA-1500 - Min Equilizer - Right Chanel15. Min Equilizer - Right Chanel
16. Kenwood KA-1500 - Loudness - Left Chanel16. Loudness - Left Chanel
17. Kenwood KA-1500 - Loudness - Right Chanel17. Loudness - Right Chanel
18. Kenwood KA-1500 - Phono Input - Left Chanel18. Phono Input - Left Chanel
19. Kenwood KA-1500 - Phono Input - Right Chanel19. Phono Input - Right Chanel

Residual Noise

These graphs display the noise levels at various volume positions. To eliminate any interference from the input signal, the input lines are shorted during the measurement. Generally, the noise is highest at the mid-point of the volume range (50%)

20. Kenwood KA-1500 - Noise - Volume 0% - Left Chanel20. Noise - Volume 0% - Left Chanel
21. Kenwood KA-1500 - Noise - Volume 0% - Right Chanel21. Noise - Volume 0% - Right Chanel
22. Kenwood KA-1500 - Noise - Volume 50% - Left Chanel22. Noise - Volume 50% - Left Chanel
23. Kenwood KA-1500 - Noise - Volume 50% - Right Chanel23. Noise - Volume 50% - Right Chanel
24. Kenwood KA-1500 - Noise - Volume 100% - Left Chanel24. Noise - Volume 100% - Left Chanel
25. Kenwood KA-1500 - Noise - Volume 100% - Right Chanel25. Noise - Volume 100% - Right Chanel

Distorsion

Total harmonic distortion (THD) is measured using a 1kHz sine wave input, with the output level adjusted to meet different conditions. Intermodulation distortion (IMD) is measured using 'two sine' input signal. THD versus voltage is measured with a 1kHz sine wave input, while THD versus frequency is measured at various output levels.

26. Kenwood KA-1500 - THD 1W 8Ω - Left Chanel26. THD 1W 8Ω - Left Chanel
27. Kenwood KA-1500 - THD 1W 8Ω - Right Chanel27. THD 1W 8Ω - Right Chanel
28. Kenwood KA-1500 - THD 20W 8Ω - Left Chanel28. THD 20W 8Ω - Left Chanel
29. Kenwood KA-1500 - THD 20W 8Ω - Right Chanel29. THD 20W 8Ω - Right Chanel
30. Kenwood KA-1500 - IMD 1W 8Ω - Left Chanel30. IMD 1W 8Ω - Left Chanel
31. Kenwood KA-1500 - IMD 1W 8Ω - Right Chanel31. IMD 1W 8Ω - Right Chanel
32. Kenwood KA-1500 - THD vs Voltage 1KHz 8Ω - Left Chanel32. THD vs Voltage 1KHz 8Ω - Left Chanel
33. Kenwood KA-1500 - THD vs Voltage 1KHz 8Ω - Right Chanel33. THD vs Voltage 1KHz 8Ω - Right Chanel
34. Kenwood KA-1500 - THD vs Frequency 1W 8Ω - Left Chanel34. THD vs Frequency 1W 8Ω - Left Chanel
35. Kenwood KA-1500 - THD vs Frequency 1W 8Ω - Right Chanel35. THD vs Frequency 1W 8Ω - Right Chanel
36. Kenwood KA-1500 - THD vs Frequency 20W 8Ω - Left Chanel36. THD vs Frequency 20W 8Ω - Left Chanel
37. Kenwood KA-1500 - THD vs Frequency 20W 8Ω - Right Chanel37. THD vs Frequency 20W 8Ω - Right Chanel

Conclusion

On this particular unit the right channel performs worse than the left, which may be due to a failed component or a dirty contact in the selector swirch.