With the new Cayin HA-300 Mk3, Cayin introduces the third generation of its reference headphone amplifier. The new edition once again relies on the legendary directly heated 300B triode, but combines it with an elaborately separated power supply and a completely hand-wired single-ended Class A circuit. The result is designed to offer maximum sonic purity for demanding headphone enthusiasts—and even allows for the operation of selected speakers.
Legendary 300B triode in single-ended Class A operation
At the heart of the new HA-300 Mk3, a 300B power tube works in a classic single-ended circuit for each channel. This design is considered by tube enthusiasts to be one of the most purist amplifier architectures of all and is valued for its exceptional transparency, musicality, and fine resolution.
Out of the box, Cayin uses selected Genalex Gold Lion PX300B tubes, which are matched in pairs and burned in before installation. Two JJ 6SN7s are used as driver tubes, operating in a dual-mono configuration to ensure the cleanest possible channel separation.
Newly developed output transformers enable power outputs of up to 6.5 watts per channel for headphones. For speakers, up to 2 x 8 watts of output power are available.



Power supply with its own tube unit
A special feature of the new HA-300 Mk3 is the consistently separate power supply. The power supply unit is housed in its own chassis and is galvanically, mechanically, and magnetically isolated from the amplifier section. This is intended to minimize interference and noise.
Here, too, Cayin relies entirely on tube technology. Two JJ GZ34 or 5AR4 tubes handle the rectification of the high-voltage supply. According to the manufacturer, no transistors or diodes are used in the signal path. Together with the toroidal transformer, this is said to enable an exceptionally high signal-to-noise ratio of 100 dB.
Suitable for almost any headphones
The HA-300 Mk3 is aimed at owners of a wide variety of headphone types. A three-stage impedance matching system allows the amplifier to be tuned for models between 8 and 600 ohms.
For power-hungry planar magnetics or high-impedance dynamic headphones, a balanced 4-pin XLR output with maximum power is available. Additionally, Cayin offers a 4.4 mm Pentaconn connection with optimized matching for particularly sensitive headphones and in-ear monitors.
More than just a headphone amplifier
Also interesting is the possibility of using the HA-300 Mk3 as a classic integrated amplifier. High-efficiency speakers can be driven directly via the speaker outputs. This positions the device not just as a headphone amp, but as a versatile tube hub for demanding music lovers.
Analog sources can be connected via either RCA or balanced XLR inputs. VU meters on the front provide the perfect retro charm and are reminiscent of classic studio equipment.
Premiere at High End Vienna 2026
If you want to experience the new Cayin HA-300 Mk3 live, you can find Cayin at High End Vienna 2026 in Hall X5, Booth T19. The amplifier will be presented to a wider audience there for the first time.
Price and availability
The Cayin HA-300 Mk3 is available now with a silver or matte black front. The suggested retail price is 5,480 euros.




