• Tuning range: FM, MW
• Power output: 35 watts per channel into 8Ω (stereo)
• Frequency response: 10Hz to 50kHz
• Total harmonic distortion: 0.3%
• Damping factor: 30
• Input sensitivity: 7mV (mic), 2.5mV (MM), 150mV (DIN), 150mV (line)
• Signal to noise ratio: 70dB (MM), 90dB (line)
• Output: 150mV (line), 30mV (DIN)
• Speaker load impedance: 4Ω (minimum)
• Semiconductors: 1 x FET, 9 x IC, 21 x transistors, 29 x diodes
• Dimensions: 18.89 x 5.87 x 14.61 inch
• Weight: 28.88 lbs
• Year: 1976

KEY FEATURES:

• Mid-Power Performance – 35WPC, great for small to medium spaces
• Classic Pioneer Styling – Blue dial, brushed aluminum, walnut veneer cabinet
• Vintage Warmth – Smooth, musical sound signature
• Flexible Inputs – Phono, aux, and tape monitor connections
• Speaker Switching – Independent A/B outputs for two pairs of speakers

REFURBISHED;

This Pioneer SX-650 has undergone careful servicing with emphasis on functional accuracy, electrical reliability, and preservation of original character.

Electrical & Functional Service

All lamps replaced, restoring correct dial and indicator illumination

Power supply and amplifier sections inspected and verified stable

Internal cleaning performed to remove dust and aging residue

Cabinet & Cosmetic Work

Wood cabinet side rails replaced with newly made wooden pieces, matched to original style and proportions

Front panel, knobs, and switches cleaned for smooth, consistent operation

Input / Output Testing

All signal paths were individually tested:

AUX input tested

PHONO input tested

TAPE input and monitor functions tested

Speaker outputs tested for both channels

Channel balance and signal integrity were confirmed across left and right outputs.

Tuner Section

FM tuner tested for stable reception and tuning accuracy

AM tuner tested and confirmed operational

Dial tracking and signal behavior verified during extended operation

Signal Measurement & Waveform Testing

To verify amplifier stability and channel accuracy, this Pioneer SX-650 was measured using a Hantek DSO2D15 digital storage oscilloscope.

A reference sine-wave signal was injected into the amplifier input

Output waveforms of both left and right channels were monitored simultaneously

Waveforms displayed clean, symmetrical sine shapes with no visible clipping, oscillation, or distortion

Channel amplitude and phase behavior were consistent, confirming proper balance and stable gain

Measurements confirmed normal operating behavior of the power amplifier stage under continuous signal load

This waveform testing confirms that the amplifier delivers clean, stable output and that the power section is functioning correctly

Final Test

Full internal and external cleaning completed

Receiver operated for extended listening and monitoring time to ensure stable, noise-free performance

Result:

 A fully serviced Pioneer SX-650 stereo receiver, electrically sound, functionally complete, and ready for reliable long-term use.

✅ Backed by 1-Year Warranty (repair or replacement)

SUGGESTED PAIRINGS:

• Acoustic Research AR-18 or AR-58B Speakers – Neutral, musical match
• Klipsch Heresy II – Dynamic, efficient pairing
• JBL L26 or 4311 Monitors – Punchy and accurate classic monitors
• Bose 301/401 Speakers – Compact room-friendly companions

👉 Perfect for vinyl enthusiasts, collectors, and audiophiles seeking a versatile Pioneer receiver with full restoration.

🎁A $100 voucher is yours instantly with any combo purchase!

PACKAGING & SHIPPING:

Secure Packaging:

• Each unit is carefully packed using:
• Nylon wrap and sealed inner carton
• Custom EPE foam corners to protect edges
• Double-wall outer box for shock resistance
• Plastic straps + handling labels to ensure safe transit

Shipping Details:

• Dispatch Time: Ships within 3 business days
• Carrier: UPS Ground (tracked & insured)
• Signature Required: Yes (as buyer’s request)
• Transit Time: Typically 3–7 business days (USA)

International Shipping:

We offer global delivery through the eBay International Shipping Program. eBay handles customs, duties, and tracking.

📦 Note: Packaging may vary slightly depending on unit size or model, but safety and protection are always our top priority.