M-504 vs Yamaha M-4
The M-4's power @ 8ω is 120W against the M-504's 165W, its signal-to-noise 118 dB against 120 dB, its thd 0.005% against 0.003%, and its damping factor >200 against >100.
AI-generated product photo — not official manufacturer imagery.
AmplifiersPower AmplifiersDiscontinued
Estimated price (community-sourced)
$400
Around — community and catalog average, updates slowly
About the M-504
The Onkyo M-504 is a stereo power amplifier produced from 1987 to 1997, known for its robust build and classic design with rosewood side panels and illuminated green power meters. It delivers 165 watts per channel into 8 ohms with a frequency response from 1 Hz to 100 kHz and a total harmonic distortion of 0.003%. The amplifier features a dual-mono construction with two large transformers and discrete output stage circuitry, providing excellent power and sound quality. It has an input sensitivity of 1V, a damping factor of 140, and a signal-to-noise ratio of 120 dB. The unit weighs approximately 22.5 kg (about 50 lbs) and measures 465 x 185 x 422 mm. It supports stable operation into 4-ohm loads and includes an unswitched 100W AC outlet. The M-504 is praised for its authoritative power, clean sound, and vintage aesthetic appeal, making it a sought-after amplifier for enthusiasts of classic HiFi equipment.
Specifications
Power Specifications
Amplification power output and characteristics
- Power @ 8Ω
- 165W @ 8Ω
- Damping Factor
- >100
- Minimum Impedance
- 4Ω
- Input Sensitivity
- 1.0V RMS
Analog Output
Analog signal output specifications
- THD
- 0.003%
- SNR
- 120 dB
Physical Dimensions
Size, weight, and appearance
- Dimensions
- 465 × 185 × 422 mm (W × H × D)
- Weight
- 22.5 kg (50 lbs)
- Available Colors
- Rosewood-look
Key Specifications
Power: 165W
Specifications are community-contributed and may not be accurate or complete. Verify all details with the manufacturer before making purchasing decisions. Terms & Conditions