2021-04-13

Audiophile Listening Chapter
Audio Note Cobra Integrated Amp with EL 34 tubes

“I held back my tears when I forked out to buy four Audio Note amplifiers: an M2 pre-amp; the 300B Conqueror power amp; after a few years, I bought the Vindicator power amp with 2A3 triode valve. … With only a few watts of output from the Vindicator, when matched with the old M2 pre-amp to drive my glossy Sapele LS 3/5As to play vocals, the sound was so beautiful, it was out of this world.”

“As a softer, more subtle push-pull amp with two EL34 per channel push-pull circuits, [the Cobra] can produce a sound close to that of a single-ended triode amp, yet it can also increase its intensity. With that comes Audio Note’s ‘Cobra’, its four-eyed viper! … Once the Cobra was launched, audiophiles bought them sight unseen, which is a miracle given this pandemic. There is only one reason – that the vacuum tube amplifier is designed by Peter Qvortrup, which gave the audiophiles their full confidence.”

“The Cobra decoder chip uses Philips TDA 1543, which definitely makes connecting to a computer or a streaming platform easier…. When it comes to the power supply, the maker specially designed double C-core transformers for the Cobra, and the double c-core transformers made in-house, combined with Audio Note’s choke, gives the Cobra a very stable power supply.”

“The digital parts emulate analogue concepts as much as possible…. Digital correction technology has been completely omitted, and the necessary filtering after decoding is performed by the analogue circuit before analogue amplification. Although this approach contradicts the design concept of most top digital manufacturers, Audio Note on the contrary has created a more natural sound, which has always been appreciated by audiophiles.”

“Although it is an integrated amp, the Cobra’s dense and dewy breath sticks on you, which makes it impossible to leave one’s seat…. The Cobra is not like the Jadis JA30 that is so condense and heavy that its sound cannot be diluted, nor is it as quaint and simple like the vintage Klangfilm 2805. It makes details very vivid on the whole, and it can enhance the flavour and charm with high fidelity…. Each channel is reportedly 28 watts, but upon actual listening, it feels more powerful, and the music at mid-frequencies is strongly appealing. It makes it easy for people to immerse themselves in the song, with its meticulous musicality.”

“When the Cobra pushes the [LS 3/5A] “baby speakers” which have the best balance, the sound is so beautiful that you won’t believe it! …When I use a USB to connect to a computer to play songs streaming on the internet on Tidal, the sound is soft and alluring, without the slightest hint of digital music. Human vocals and musical instruments are equally smooth and textured. … The sound is extremely natural and open.

“Tube amplifier that use EL 34 valves can be as forceful as a bull, such as the Marantz 9, or as gentle and graceful as Audion’s Sterling. Audio Note’s Cobra easily blends the characteristics of the two. … Compared with other amps that use EL 34 tubes, the Cobra wins hands down!”

– W.K. Wong Audiotechnique March 2021