HA-300MK2

Direct Heated Triode Vacuum Tube Headphone Amplifier

The Star is Reborn

Work hard and dig deep with 20 years of impeccable track record.

Pushing the envelop of tube amplification to deliver practicality, performance and refinement.

Tube Amplifier Holy Grail

The Pursuit of Direct Heated Triode (DHT)

DHT refers to triode tubes that use the cathode as the filament and will heat up the cathode directly.

Minimal approach, offers stellar dynamic, transient and transparent, extremely well-received by audiophiles.

A challenge for headphone applications. Low tolerance to shock and vibration, sensitive to hum/interference.

The Irresistible 300B

The 300B is the most renowned and sought after DHT because of its dreamy tonal characteristic.
HA-300MK2 uses a matched pair of Gold Lion Genelex PX300B low-noise audio triode as power output tubes.

• Endure and passed the toughest tests for reliability

• Natural, sensible and realistic sound signature

• Impressive frequency extension

Purist’s One-Way Ticket 

Less is More

Single-ended Triode (SET) Amplifier uses a single triode vacuum tube to produce amplified output without splitting the musical signal into parts.

2-stage amplification, a pair of driver tube amplifies signal voltage so that the 300B output tube will perform its amplification at a very linear condition.

Simplicity circuit design. Displace the beautiful tone of your vacuum tubes without any cancellation.

Single-ended Driver Stage 

Cayin developed many 300B based SET amplifiers and 6SN7 is always the first choice for driver tube.
HA-300MK2 uses a matched pair of Tung-Sol 6SN7GTB to complete the two-stages SET amplification.

• Low noise, high price-performance and highly reliable
• Super linear and natural sounding
• A classical tube combination adopted in many

Cayin SET amplifier implementations

Tube Regulated Power Supply

2-Boxes Design

Outboard Power Supply minimize ripple effect, offer a clean, low-noise power to amplification circuit.
Multi-stage tube regulated power supply circuit, feed power to different amplification stages independently.

New Old Stock (NOS) Rectifier Tubes 

HA-300MK2 uses 4 x NOS 22DE4 from RCA, one of the best versions of 22DE4 available in tube market.
Convert incoming power source to DC current,  provides cleanest power with minimum interference for the amplification circuit.

• Unlike output tubes, rectifier tubes don’t involve heavy lifting load, they can last very long without deteriorate.

• No matching requirement, replace on per piece based.

Power Supply Transformer

The outboard power supply is driven by a high inductance high efficiency toroidal power transformer.

Cayin design and wind the Power transformers in-house.

Low leaking design for headphone applications.

Premium Vacuum Tubes

Driver Tubes: Tung-Sol 6SN7GTB (Matched Pair)

Output Tubes: Genalex PX300B (Matched Pair)

Rectifier: NOS RCA 22DE4 x 4

Transformer-coupled Design

Balanced Driven from Single-ended Triode Amplifier 

The 300B SET output drives a pair of proprietary output transformers, support both headphones and speakers.
The secondary winding of the output transformers provide an alternative phase and compose a balanced output, enables balanced driven from an SET amplification circuit.
Both single-ended and balanced headphone output are "original" outputs from the transformers.

In-house Designed and Winded Transformers 

With a pair of EI Transformers,  HA-300MK2 delivers a natural and realistic sound across the frequency range.
Cayin design and wind the all transformers in-house because they play a vital role in our amplifiers.
• Total freedom in specifying the requirements and   winding instructions.
• Total control on material and craftsmanship.

This Is All You'll Ever Need

Impedance Matched Phone Out

Optimized its output to handle the headphone loading according to three headphone impedance settings
Low (L): 8Ω~64Ω; Medium (M): 65Ω-250Ω; High (H): 251Ω~600Ω.
Matching headphone impedance should produce a natural sound with well-defined bass reproduction, it is different from gain control of solid state amplifier.
Planar Headphones are more sensitive to impedance matching than dynamic headphones but users can try out different impedance settings.

Carefully Optimized Headphone Outputs

HA-300MK2 offers three headphone outputs: 6.3mm single-ended, 4.4mm balanced, and 4-pin XLR balanced.
The XLR4 output is a full-fetched output but the 4.4mm output is optimized for wider range of headphones,
including high sensitivity portable headphones.
• 4.4mm is level-matched, lower noise, lower power  output with the same audio performance
• at LOW headphone impedance, the 4.4mm output  delivers roughly 70% of 4-pin XLR output only.

Powerful and Effortless

Combinations all audiophiles will cherish and admired:

purity of single-ended triode amplifier, dreamy sound signature of 300B, and authoritative dynamic and control when called for.
With up to 6w per channel, provides all the power you need to handle vast selection of headphones, from portable friendly dynamics to extremely demanding planar.

Professionally Precision

Low noise low distortion electronic controlled resistor ladder analogue volume controller JRC MUSE72320V, commonly used in high-end preamplifiers and streamers.
4-channel in one integrated controller offers high precision and zero channel imbalanced.
ALPS balanced potentiometer as 41-steps encoder to provide precise and intuitive control that we are all familiar with.

Interface Facilitates Functions

Quick-release Connection 
Lock-on & quick-release aviation grade copper connectors.
Silver plated Teflon umbilical cable connects between outboard power supply and amplifier circuit.

Dual Inputs

Balanced (XLR) and Single-ended (RCA) to cover a variety of inputs.
Balanced input will go through a pair of input transformers, the + and – half cycle will merge  to become a single-ended signal.

Speaker Output

Users can toggle between speaker and headphone output.
With 8W per channel Class A output, the amplifier can driver high sensitive speakers, or common bookshelf speaker in a small listening area.

High quality solid brass speaker terminals.

Enhance Your Daily Usage

Anti-Interference Improves Listening Experience

Custom-made silica gel shock absorbers between critical tube components, chassis mainframe and tube socket, remove microphonic effectively.
Reinforcing shielding of transformers and effective circuit layout to minimize interference.

60sec startup delay circuit.
Enhances circuit protection and minimizes pop noise during startup.

Bundled Protection

Specially designed vacuum tube shielding cage to protect users from touching the red hot vacuum tubes during operation.

Removing and installing with ease, safe and flexible for different needs.

The Art of Black Finishing

13.5mm brushed Aluminum-Magnesium Alloy front panel, added strength and corrosion resistance to the amplifier.

The panel is black anodized, it is extremely durable and protect the amplifier from scratches.

The Hidden Details

The chassis and transformer pots are treated by our proprietary 14 rounds of crafting process
composed of scratch, spray, sanding and baking.
The high gross final finishing endows a refined and delicate texture as well as protecting the amplifier from years of long service.