Power Holdings Inc is an international consumer audio product development and distribution company. We specialize in marketing high end audio components and accessories to music enthusiasts in North America.
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Direct Heated Triode Vacuum Tube Headphone Amplifier
Work hard and dig deep with 20 years of impeccable track record.
Pushing the envelop of tube amplification to deliver practicality, performance and refinement.
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 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.
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.
HA-300MK2 uses a matched pair of Tung-Sol 6SN7GTB to complete the two-stages SET amplification.
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.
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.
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.
Driver Tubes: Tung-Sol 6SN7GTB (Matched Pair)
Output Tubes: Genalex PX300B (Matched Pair)
Rectifier: NOS RCA 22DE4 x 4
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.
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.
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.
The XLR4 output is a full-fetched output but the 4.4mm output is optimized for a wider range of headphones, including high sensitivity portable headphones.
Combinations all audiophiles will cherish and admire: 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.
Low Noise low distortion electronic controller 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 intiuative control that we are all familiar with.
Lock-on & quick release aviation grade copper connectors.
Silver plated Teflon umbilical cable connects between outboard power supply and amplifier circuit.
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.
Users can toggle between speaker and headphone output.
With 8W per channel Class A output, the amplifier can drive high sensitive speakers, or common bookshelf speaker in a small listening area.
High quality solid brass speaker terminals.
60sec startup delay circuit.
Enhances circuit protection and minimizes pop noise during startup.
Specifically 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.
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 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.
Welcome to Power Holdings Inc! We have been in business since 2008 providing audiophiles with equipment and customer service that we are proud of. Our brands are sold throughout the USA and Canada both online and in retail stores. Please see our list of AUTHORIZED RESELLERS to find a dealer near you. You can also purchase these products on this website. If you have any questions please feel free to Contact Us.
Enjoy the music, Arthur G H Power IV