Product Description
A Comprehensive Upgrade
As the third-generation model in the HA-300 series, the HA-300 MK3 builds on the acclaimed architecture of the MK2 with major advances in components, circuitry, craftsmanship, and industrial design. From sonic refinement to day-to-day usability, every detail reflects Cayin's ongoing pursuit of acoustic excellence.
Pure Single-Ended Class A Design
The HA-300 MK3 continues the series' classic single-ended pure Class A tube amplifier design, combining premium tubes with a newly upgraded circuit to achieve an exceptional balance of musicality and technical performance.
JJ GZ34 / 5AR4 Rectifier Tubes
The HA-300 MK3 employs two JJ GZ34 / 5AR4 tubes and an upgraded tube rectification circuit delivering improved efficiency while preserving the distinctive appeal of tube-based power supply design.
JJ 6SN7 Voltage Amplification Tubes
The JJ 6SN7 tubes provide low noise and high resolution, enabling accurate voltage gain and excellent detail retrieval while laying a clean foundation for the subsequent amplification stages.
Genalex Gold Lion PX300B Power Tubes
Known for their warm, richly textured character, these tubes deliver a full, delicate midrange, smooth, transparent highs, and deep, well-controlled bass.
Third-Gen Circuit Upgrade
The HA-300 MK3 adopts a physically separated power supply and main amplifier chassis, providing cleaner energy delivery and improved isolation from interference. The voltage amplification stage incorporates a low-noise regulated circuit with independent staged power delivery, preserving the integrity of the original audio signal.
In addition, the HA-300 MK3 has been specially optimized for IEM compatibility, making it suitable for a much wider range of headphones than before.
Refined in Every Detail
The updated transformer housing design removes the previous aluminum decorative plates, resulting in a cleaner, lighter visual appearance and improving heat dissipation. For improved wear resistance and reduced fingerprint visibility, the HA-300 MK3 chassis is finished with a fine sandblasted texture. A newly designed family-style tube cage replaces the previous design, providing stronger protection.
Key Features
- Third-Generation Custom Transformers - The HA-300 MK3 is equipped with a third-gen wide-bandwidth EI output transformer and toroidal power transformer, developed specifically for this model. These transformers provide significantly improved shielding and reduced noise interference.
- DUELUND Coupling Capacitors - The headphone amplifier uses DUELUND coupling capacitors from Denmark, widely regarded as an ideal match for tube amplifiers. Their low distortion and excellent transmission characteristics enhance detail and layering.
- New Gold-Plated Tube Sockets - New premium gold-plated tube sockets provide better conductivity and more stable contact than conventional ceramic gold-plated pin sockets.
- 60-Second Startup Delay - A 60-second delayed mute function allows the amplifier to warm up properly after power-on, helping it reach optimal operating condition before playback begins.
Technical Specifications
- Amplifier Type: Pure Single-Ended Class A Triode, Vacuum Tube
- Design: Two-piece split construction (Main Amplifier & Separate Power Supply)
- Power Output (Headphones):
- 4-pin XLR (Balanced): 6,500 mW + 6,500 mW
- 6.3mm Jack (Single-Ended): 6,000 mW + 6,000 mW
- 4.4mm Pentaconn (IEM Optimized): 1,600 mW + 1,600 mW
- Speaker Output: Drives 4 to 8 ohm loudspeakers
- Tube Complement:
- Power Tubes: Genalex Gold Lion PX300B (Matched Pair)
- Voltage Amplification: JJ 6SN7
- Rectifier: JJ GZ34 / 5AR4 (Allows for wide tube-rolling)
- Build & Dimensions
- Output Transformers: Third-generation wide-bandwidth EI design
- Internal Wiring: Point-to-point (PTP) hand-wired construction
- Dimensions:
- Power Supply: 6.26" × 13.58" × 8.07"
- Main Amplifier: 11.26" × 14.49" × 8.07"
- Weight:
- Power Supply: 22 lbs
- Main Amplifier: 37 lbs









