The RX-503 delivers 33 watts per channel into 8 ohms, with a frequency response of 20Hz to 20kHz and a damping factor of 35, providing adequate control for most loudspeakers of the period. The amplifier section employs direct-coupled circuitry and is rated for 4-ohm operation at 50 watts per channel, though Rotel recommends 8-ohm loudspeakers for normal use. Total harmonic distortion is quoted at 0.5%.
The input complement is practical and well-arranged: a moving-magnet phono input (2mV sensitivity, 50kΩ impedance), an auxiliary line input, and two tape monitor loops with both RCA and DIN connections. A front-panel headphone socket is provided, along with switching for two pairs of loudspeakers. Tone controls offer ±10dB at 100Hz and 10kHz, with a loudness contour switch and a high-filter (-12dB/octave at 8kHz) for taming bright recordings.
The tuner section covers FM (87–108MHz) and MW (525–1605kHz), with a quoted signal-to-noise ratio of 70dB in mono and 65dB in stereo. A muting circuit is fitted to suppress inter-station noise, and the tuning scale is clearly marked for ease of use.
Technical Specifications (Source: HiFi Engine / HiFi Wiki)
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Type: AM/FM Stereo Receiver
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Power Output: 33W RMS per channel into 8Ω (stereo); 50W RMS per channel into 4Ω (1kHz)
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Frequency Response: 20Hz – 20kHz
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Total Harmonic Distortion: 0.5%
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Damping Factor: 35 (8Ω)
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Input Sensitivity & Impedance:
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Phono (MM): 2mV / 50kΩ
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Aux: 150mV / 50kΩ
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Tape Play: 150mV / 50kΩ
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Outputs:
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Tone Controls: ±10dB at 100Hz (bass); ±10dB at 10kHz (treble)
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Loudness: +10dB at 100Hz / +3dB at 10kHz
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High Filter: -12dB/octave at 8kHz
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Tuner:
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Loudspeaker Terminals: 2 pairs (A/B switching)
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Dimensions (W x H x D): 480 x 145 x 325 mm
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Weight: 10 kg
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Year of Production: 1977 – 1981
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Country of Origin: Japan
Why Buy From Us
With over 40 years of experience in the Hi-Fi industry, we are well placed to assess and test equipment of this type. Every item we list is fully inspected and tested before sale — this unit was checked by Callum in our workshop.
When you buy from us you can expect:
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Full inspection and testing prior to listing — not simply a visual check
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A 3-month guarantee on every item we sell
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Transparent descriptions with no omissions
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Professional packaging to ensure safe delivery
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After-sales support available by phone or email should you have any questions
Summary
The Rotel RX-503 is a well-built Japanese receiver from the late 1970s, offering a sensible combination of power, features, and tuner performance in a full-width chassis. This example is in good used condition with some cosmetic marks on the front panel and tuning knob, whilst the wood veneer side panels remain in good order. This is a single-unit listing. Please feel free to get in touch with any questions prior to purchase.
