Предусилители — Kondo Audio Note Japan G-700i

The G-700i is a stereo preamplifier for line sources made by Kondo Audio Note Japan that sits between the G-70 and the G-1000i in the company's range. Kondo describes it as joining the mature character of the G-70 with the expressive power of the G-1000, and it arrives as a two box design with a dedicated power supply.

Key specs that matter

Inside are four 6072 and one EZ81 rectifier. Gain is 25 dB, and the response runs from 10 Hz to 280 kHz at minus 3 dB into a 100 kohm load through the unbalanced path. The rear panel carries four RCA input pairs plus one XLR pair, both handled as unbalanced connections at 50 kohm input impedance. Outputs comprise two RCA pairs plus one XLR pair, again unbalanced, rated for loads above 20 kohm. Output impedance is 400 ohm, which gives a low cutoff of 18.5 Hz into a 20 kohm load. Noise stays under 0.15 mV and power consumption is 35 W. The main unit measures 302 x 160 x 412 mm and weighs 14.5 kg, and the power supply is 160 x 160 x 412 mm at 12 kg.

Engineering and use context

Level control uses a newly developed 50 step attenuator built from MELF type resistors on a high grade rotary switch, and the whole unit sits in its own copper case to keep it quiet. A second housing holds the supply so that vibration and electromagnetic fields from the transformer stay away from the signal circuit. Decoupling capacitors are placed close to the amplification module to keep the signal loop short, and the heaters run from a shunt type supply. The chassis is pure copper and the wiring is done by hand. Parts include pure silver foil capacitors, pure silver lead resistors, SSW wire, silver-palladium plated RCA jacks and zirconia valve sockets, and Kondo recommends its ACz AVOCADO power cable for the unit. Because the XLR connections are unbalanced, they serve as alternative connectors rather than a true balanced circuit.

Pairing

The 25 dB gain and the rating for loads above 20 kohm point to power amplifiers with a normal input impedance, valve or transistor. A phono source can come from the Kondo GE-7i, which shares the same main and supply chassis sizes, so the four boxes form an even stack. Above the G-700i Kondo lists the G-1000i as its top preamplifier, and the M7 Heritage appears in the same preamplifier section of the catalogue.

Alternatives

The Kondo G-72i is a further line level model from the same Japanese catalogue, positioned as a separate step next to the G-700i.