The Pioneer SX-780 is a classic 45-watt-per-channel vintage stereo receiver produced around 1978–1979 during Pioneer's acclaimed "silver face" era. 
Key Specifications

• Power Output: 45 watts per channel into 8 ohms (from 20Hz to 20kHz with 0.05% Total Harmonic Distortion).
• Tuning Range: FM and AM.
• Frequency Response: 5Hz to 80kHz (line input).
• Damping Factor: 30 (8 ohms).
• Dimensions: 18-7/8" x 5-1/2" x 12-5/8" (480 x 140 x 320 mm).
• Weight: Roughly 24 lbs 11 oz (11.2 kg). 
• Features and Controls
• • Inputs: Dedicated phono input for turntable vinyl playback, auxiliary inputs, and dual tape monitor loops.
  • Tone Controls: Bass and treble adjustment knobs with a tone defeat option, plus low and high audio filters.
  • Loudness Contour: Boosts low-frequency bass response when listening at lower volume levels.
  • Speaker Output: Supports speaker systems A, B, or A+B with a minimum load impedance of 4 ohms.
• Widely regarded as one of Pioneer's best-selling and most popular mid-tier vintage receivers, praised for its warm analog sound signature and retro aesthetic.
  
• This Pioneer has just been lightly serviced. All pots and switches have been cleaned-Fully Tested for extended periods. New LED lighting. Sounds and looks fantastic. There are a couple dings on the wood cabinet but still looks nice. Usual age related scratched and scuffs.