• Country
• Great Britain (UK)

• Manufacturer / Brand
• Quad (Brand); Acoustical Manufacturing Co. Ltd.; Huntingdon

• Year
• 1969–1972 ?

• Category
• Audio Amplifier or -mixer

• Radiomuseum.org ID
• 128990

Click on the schematic thumbnail to request the schematic as a free document.

• Number of Transistors
• Semiconductors present.

• Semiconductors

• Main principle
• Audio-Amplification

• Wave bands
• - without

• Power type and voltage
• Alternating Current supply (AC) / 50-60 Hz, 100-25 or 200-250 Volt

• Loudspeaker
• - This model requires external speaker(s).

• Power out
• 90 W (unknown quality)

• Material
• Metal case

• from Radiomuseum.org
• Model: Quad 303 - Quad Brand; Acoustical

• Shape
• Chassis only or for «building in»

• Dimensions (WHD)
• 120 x 159 x 324 mm / 4.7 x 6.3 x 12.8 inch

• Notes

• The Quad 303: A High-Fidelity Powerhouse

  Ideal for powering any loudspeaker between 4 and 16 ohms, the Quad 303 delivers smooth, high-quality audio to your home. Each channel produces up to 45 watts, driven by an ingenious transistor circuit for flawless performance.

  Unmatched Clarity and Stability:

  Distortion-free: Forget about unwanted noise. The 303's audio range boasts incredibly low harmonic and intermodulation distortion. Transistor triples are employed to provide a completely symmetrical output stage, quiescent current independent of junction temperature, and symmetrical current and voltage limiting.

  Stable design: No matter the load, this amplifier stays under control. Drive any speaker with confidence.

  Versatility and Power:

  Independent channels: Use both channels together or separately for ultimate flexibility.

  Low-impedance capability: Push the limits with continuous power for 4-ohm loads and below.

  Heat management: Extended use with demanding loads is no problem thanks to the efficient heat sink.

  Caution: Don't parallel the outputs without current sharing to avoid damage.

  The Quad 303 is a true legend in the audio world, built for discerning listeners who demand the best.

  Specifications

  Power output:	45 watts per channel into 8 Ω (stereo)
  Frequency response:	30 Hz to 35 kHz
  Total harmonic distortion:	0.1%
  Input sensitivity:	0.5V for 45 W into 8 Ω
  Signal-to-noise ratio:	100 dB
  Crosstalk	> 60 dB
  Hum & Noise:	-96 dB ref full power
  Speaker load impedance:	4 Ω to 16 Ω

   

• Net weight (2.2 lb = 1 kg)
• 8.2 kg / 18 lb 1 oz (18.062 lb)

• Price in first year of sale
• 170,000.00 ITL

• Source of data
• -- Collector info (Sammler)

• Mentioned in
• Advertisement - Suono HiFi Stereo, n.13, Agosto 1972 - Italy

• Literature/Schematics (1)
• -- Original prospect or advert

• Author
• Model page created by Gottfried Silberhorn. See "Data change" for further contributors.

• Other Models

• Here you find 38 models, 37 with images and 15 with schematics for wireless sets etc. In French: TSF for Télégraphie sans fil.
  All listed radios etc. from Quad (Brand); Acoustical Manufacturing Co. Ltd.; Huntingdon