Esoteric Audio Research E.A.R. 509

General

1977 Esoteric Audio Research Ltd., short EAR, was founded. His first product, the 100 watt monoblock 509, has as a special feature the exclusive "interface" between output transformer and power tube, the "balanced bridging mode". The fact that his designs do not require feedback is another characteristic of Paravicini's developments. The 509 proves that tubes could stand up to transistors in every respect. In the lab they showed measured values - e.g. a bandwidth of 9 to 85'000 Hz (-3 dB) - that were completely beyond retro sound.

The 509 professional power amplifier was repeatedly used as a comparison reference in specialist magazines to test the qualities of top systems. The fact that the 509 emerged as the winner in all these comparisons explains why this power amplifier is still being built today.

Data

General

• Manufacturer: Esoteric Audio Research
• Model: 509
• Years of manufacture:
• Made in:
• Color:
• Dimensions:12"(30cm)W10"(25.4cm)D 6"(15cm)H
• Weight:18kg
• Original price approx.:9.867 €

Connections

• list here the connection options, if known.

Specifications

• Output power: (20Hz-20kHz <0,25% in evaluate load THD) 100W
• Frequency response: 8Hz-30kHz +0-1 dB
• 'Frequency Response: 3 Hz-80KHz + 0.3 dB
• 'Power Bandwidth: -3dB, 0.5% THD 12Hz-60kHz
• I.M.D.: at any level from 100mW-100W of equal power <0.2%.
• 'Output Attenuation Factor: (0.4ohm + 4UH) 20
• 'Signal to Noise Ratio: from 100W to 96dB
• 'Input sensitivity (unbalanced): 1.2
• 'Input impedance (unbalanced): 25kOhm
• Power consumption: 180V.A.

Special Features

• here, if available

Remarks

Other models of the same series:

Pictures

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