14 March 2020

SONY TA-N77ES (1988) - Digital to Analog

amplifier

Introduced in 1988 the SONY TA-N77ES was the only power amplifier ever from SONY to support large VU meters as a visual element. ​Power amplifiers are usually tested when hooked up to 8-ohm laboratory resistors. While results may look fine on a spec sheet, they simply ignore an undeniable fact. Real loudspeakers - even those nominally rated at 8 ohms - simply refuse to behave like laboratory resistors. While the resistor presents a simple impedance that's constant at all audio frequencies, the speaker presents a complex impedance that varies dramatically. A typical "8-ohm" loudspeaker can have impedance peaks higher than 30 ohms and impedance dips lower than 3 ohms! And here's the catch: as impedance drops, more and more current is demanded from the amplifier. 

Thanks to large power transformers, generous power supplies, big output transistors and massive heat sinks, the SONY TA-N77ES produce this current in casual disregard of loads. In preference to inexpensive integrated circuit "power packs" SONY ES insists on individual (discrete) output transistors. Sony's carefully-selected discrete transistors cost more, but their enhanced cooling, proven reliability and superior frequency response make them more than worth the cost. To reduce resonance and vibration Sony used a G-Base made of calcium carbonate reinforced with glass fibers, a unique compound similar in composition to marble. To accompany the SONY TA-N77ES power amplifier there were two remote controlled preamplifiers, the SONY TA-E77ES and the TA-E77ESD with added Digital inputs. Technical data: 200 W/ch 20-20,000 Hz 8 ohm THD 0.004% Dimensions: 470 W x 185 H x 440 D mm, Weight: 25 kg.


amplifier

amplifier

amplifier

amplifier