The Cayin HA-2A Tube Headphone Amplifier is a masterpiece

The Cayin HA-2A Tube Headphone Amplifier is a masterpiece that stands out from the rest of the HA series as Cayin’s first vacuum tube headphone amplifier designed exclusively with vintage NOS (New Old Stock) tubes. These tubes, having never been used and sourced from old production, are the key to unlocking the HA-2A’s unparalleled audio performance. With a total of five tubes, including the RCA 17AX4GT rectifier tube that supplies power to the preamp tubes’ plate electrode, the HA-2A fully showcases the unique harmonic richness and warm, delicate audio characteristics that only tube rectification can provide. The preamp and power tubes feature the renowned “Bugle Boy” Amperex vacuum tubes, a brand that serious vacuum tube enthusiasts know and love. Before installation, each pair of Amperex ECF82/6U8 in the preamp stage and Amperex 17BF11 in the power output stage undergoes rigorous in-house testing and matching to ensure optimal performance. With 30 years of experience in crafting tube amplifiers, Cayin brings to the table an unrivalled level of know-how and development expertise in the vacuum tube audio business. The HA-2A is a testament to this, utilizing only the finest NOS vintage tubes from Cayin’s extensive inventory, making it a true masterpiece in the world of high-end audio.

The HA-2A is the latest addition to Cayin’s renowned HA headphone amplifier series, which includes the HA-300MKii, HA-6A, and HA-3A. The HA-2A maintains a consistent layout and panel style with the other HA series amplifiers, featuring dual cold-light VU meters. Moreover, the HA-2A is also a part of Cayin’s new desktop system, which consists of four components: the iDAP-8 digital transport, iDAC-8 DAC, iHA-8 fully balanced Class A solid-state headphone amplifier, and the HA-2A single-ended Class A vacuum tube headphone amplifier. Together, these four components form a compact and versatile desktop audio headphone system, offering users the opportunity to experience the unique characteristics of both tube and solid-state amplification, catering to different sonic preferences.

Dragon Cable Recommendation: We recommend pairing the Cayin HA-2A Tube Headphone Amplifier. The Silver Dragon Interconnect is one of our best-selling cables at Moon Audio. Sold in Pairs, it is our top-of-the-line silver conductor-based interconnect. With a braided geometry and amazing shielding, this interconnect is a remarkable solution where noise isolation is key.

Vintage Vacuum Tubes for Unprecedented Sound Quality

With three decades of experience in crafting tube amplifiers, Cayin has amassed a wealth of knowledge and expertise in vacuum tube audio technology. The company’s extensive research and vast inventory of various audio tubes have played a crucial role in the development of the HA-2A. By exclusively using NOS vintage tubes, the HA-2A can be considered a showcase of the finest tubes from Cayin’s inventory.

Amperex, a well-known vacuum tube brand among enthusiasts, has a history that spans two distinct stages. According to Wikipedia, “Amperex Electronic, originally located at 79 Washington Street in Brooklyn, New York, was a long-established manufacturer of transmitting tubes when they were acquired by the Dutch firm, Philips, (known more widely as Norelco in the US), around 1955. Philips continued to improve and enlarge the tube plant in New York but also used the Amperex name to distribute their new line of Dutch-made miniature tubes, (12AX7, 12AU7, 12AT7) to feed the booming U.S. hi-fi market.”

It is important to note that the ECF82/6U8 and 17BF11 tubes used in the Cayin HA-2A were most likely produced in the early 1950s, placing them within the American production period of Amperex, rather than the later Dutch production period. These specific tube types were commonly used in the audio sections of early tube televisions and nearly became the standard configuration for TV audio during that era.

A Captivating and Finely-Tuned Sound Experience

The Amperex ECF82/6U8 stands as a remarkable composite tube, seamlessly blending a high-gain pentode with a medium-gain triode. The skilled design engineers at Cayin leverage its inherent low internal resistance and minimal noise characteristics. Through a series of inventive design approaches, unique wiring methods, and strategic power supply arrangements, they have crafted an audio experience that is nothing short of exceptional. This amalgamation of elements culminates in an output characterized by richness, warmth, balance, and harmonious sound—a treat for any audiophile.

Now, let’s delve into the realm of the Amperex 17BF11, another dual pentode composite tube with a storied history. Originally, it found its place in early applications where one pentode handled voltage amplification while the other managed power amplification. However, in the hands of Cayin’s talented engineers, particularly in their HA-2A design, this tube takes on a new life. Here, it is carefully orchestrated to function exclusively in a single-ended class A mode.

To achieve this, the gain circuit has been meticulously crafted, ensuring optimal performance in this specialized setup. Cayin’s engineers have also introduced their own Z11 iron core EI output transformer into the mix. This transformer, developed in-house, plays a pivotal role in driving the headphones to deliver a sound experience that is both captivating and finely tuned. It is this blend of historical prowess and innovative design that makes the Amperex 17BF11 in the HA-2A a standout component in the world of audio amplification.