JD302BRC Integrated Stereo Tube Amplifier




The Design Challenge: Build a stereo tube amplifier with a sound quality that equals or exceeds the best in high end audio equipment. Included were two major criteria, make sure designs are reliable and can be sold at value prices. The Engineering Result: An integrated stereo tube amplifier that can be hooked up directly to a CD player and two speakers. The Sound: High end audio tube performance at a value price.

Construction Details and Features:
  • Fully Integrated Stereo Amplifier: Input 500mV driving 50 watts, maximum 75 watts output
  • Remote Control
  • Multiple Inputs: Front mounted selector switch-CD, Tape Recorder, Tuner and Aux. (for TV, VCR or Computer)
  • Bypass Switch: This feature enables the amp to be use as a power or integrated amplifier
  • Custom Wound Audio Transformers with a core of German grain oriented silicon steel. 15th generation proprietary design. Secondary can be configured for a 4 ohm or 8 ohm load
  • Easy Biasing with top panel bias testing terminal with bias adjustment controls.
  • State of the Art Components: Blue ALPS audio potentiometer, gold plated RCA input jacks and one set of XLR
  • Fixed and Variable Outputs.

    • Technical Specifications:
    Maximum Power Output: 75 W per channel at 8 ohms, 1KHz
    Rated Output Power: 50 W per channel at 8 ohms, 25Hz to 60KHz
    Frequency Response: (at 1 watt into 8 ohms) 8Hz to 130KHz + 1dB
    Bandwidth: 13Hz to 80KHz + 3dB; 0dB 50 W 1KHz
    Distortion THD + N: Less than 1% at 50 W output, 28Hz to 15KHz
    Input Impedance: 100Kohms
    Input Sensitivity: 500mV at 1KHz for 50 watt output
    Output Impedance: 4 ohms and 8 ohms
    Negative Feedback: Less than 5 dB
    Noise and Hum: 85dB below rated output
    Tube Complement: 2 matched pairs (4) of 6CA7/EL34 power output; 2 pcs. 12AX7A/ECC83 pre-amplifier; 2 pcs. 12AT7/ECC81 power drivers
    Power Requirements: 110V-120 VAC 60Hz 180 watts-standby, 450 watts maximum (220 VAC 50Hz option)
    Dimensions: 17 inches (43cm) wide by 15 inches (38cm) deep by 7.5 inches (19 cm) high
    Weight: 48 pounds (18 Kg) net, approximately 55 pounds (21 Kg) packaged
    Warranty: Two year limited parts and labor. One year or 1000 hours whichever comes first on Jolida Tubes
    Fuse: 110 - 120 VAC, 6.3 Fast Amp Blo; 200 - 240 VAC, 3 Amp Fast Blo