HiFiMan HM901s Portable Music Player with MINIBOX Gold Amplifier Card

DSD Support Enhanced
DSD (Direct Stream Digital) files can be enjoyed on your HM9O1s with high quality playback.

The Premium Choice: ES9018 DAC*2
What is the secret to the best-sounding experience possible? The HM9O1S utilizes a pair of the top-of-the-line DAC chips from ESS Technology. The ES9018 is the one of, It not the most Impressive and high performance DAC chips available. It took the HiFiMan development team countless hours to maximize the potential of this device: incorporating two chips per each Individual channel.

The result is a warm sound, emphasizing phenomenal midrange reproduction, largely improving upon the dry, cold and analytical nature previously found with a poor single ES9018 chip. As such, the HM9O1s raises the bar and sets a new standard for high-resolution portable audio players. Using a pair of ES9018 chips achieves a wider sound stage and realizing extremely high detail separation.

Optimized Analog Circuit Design
• The key to the excellent sound? 2 0PA627 and 0PA2107 op-amps
• Instead of using the standard design in the data sheet, the HM9O1s has highly-optimized custom circuit design for the ES9018
• High & low gain modes switchable for corresponding headphone and earphone loads

Dual Voltage Design: Doubled Divine Sound
Unlike the single battery design commonly found with other portable music players, the HM9O1s utilizes a dual-voltage solution, delivering +/- 7.4 volts. 2,000 mA and achieving outstanding results. This design helps eliminate noise from the power-supply, allowing you to focus on your music without distractions. No coupling capacitors and has a wider frequency response to reproduce near perfect live concert recording. Moreover, HM9O15 relies on Its clever relay design to further Improve the sound quality.

Advanced Step Potentiometer
patented step analog volume control is designed for precise control and accurate channel balance. it removes the carbon film that tends to wear out easily. The resistors In both channels of the step potentiometer can be paired to make sure they are 100% Identical. No-gain control circuit delivers performance unmatched by the digital volume chip. Digital volume control chips with no abatement from digital high frequency noise can result in poor sound quality. HM9O1s is compatible to most earphones and headphones in the market by simply changing the amp module.

Uncompromising Sound Quality
Potentiometer for Volume Control
Carbon film resistors lack accuracy. Each channel can reach 5-10% in error production. This results in unbalanced soundstage and audible distortion. Digital volume control chips with no digital high frequency noise abatement can result in poor sound quality.

The patented step analog volume control is designed for precise control and accurate channel balance (with less than 0.001 in errors). The resistors in both channels of the step potentiometer are painstakingly paired to ensure that they are functionally identical. This results in excellent channel balance and soundstage Furthermore, in order to drive earphones of high sensitivity, HiFiMan's Advanced Step Potentiometer has a better and smarter gradual attenuation design, particularly at low volumes. This helps avoid inconsistent volume levels and channel imbalance when increasing or decreasing the volume.

Modular Amplifier Cards
Personal audio comes with headphones with high, low impedance and sensitivity, over-ear, on-ear designs. This also includes highly sensitive in-ear monitors or earphones. As such, it is incredibly difficult to satisfy the various requirements of all these units with a single circuit. The HM9O1s features a user-replaceable slot for amplifier cards. As a result, it is now possible to use different cards to best fit the specific requirements of each headphone/ear phone. The HM9O1s offers true balanced output capability, increasing resistance to interference, widening the soundstage and improving detail and separation.

MINIBOX Gold Amplifier Card

The unique circuit design without coupling capacitor achieves the fidelity to reproduce closer-to-the-real sound of music by largely reducing distortion. Bringing high fidelity live music to your ears is no longer just a fantasy. Be prepared to have your ears bathed in audio delight. MINI BOX Gold renders the sounding beautifully rounded, relaxed and. With a clear high pitch, a rounded, exuberant mid and the solid texture of the low, the musicality is smooth and velvety.

About The Designer
Hi-fi enthusiasts call him Master Three Stone. Equipped with passion and expertise, Three Stone is also the mastermind behind the first MINIBOX card, receiving wide acclaims from many HiFiMan users for its powerful drive and excellent sound quality. The upgraded new MINIBOX Gold, again, vividly reflects Three Stone's Innovative concept of design while raising the industry standards to new heights.

For the First Time in History!
The Metal Can duo with commercial amp card. The Metal Can costs ten times more expensive than its plastic counter part. It is very popular in aerospace and military industries for its excellent temperature stability and resistance to electromagnetic interference. In hi-fi audio, its superior reliability renders excellent sounding experience. Hence the name "Gold".

In the Name of the Gold High Performance Op Amp from Texas Instruments
HiFiMan is the first manufacturer to boldly include the high performance metal can from texas instruments in the commercial amplifier card design

Sublime Sounding Experience
There are up to two OPA637SM and eight BUF634U in the new MIN IBOX Gold design providing a super wide frequency range and featuring the world's best SNR. It generates smooth and rounded sound and effortlessly makes -t extremely exuberant.

Dynamic and Powerful
MINIBOX Gold is so powerful with its upgraded 440mW drive, equal to 15 iPhone6s working altogether. It's high performance will drive some of the most demanding headphones on the market and produce the listening experience you have ever dreamt for. When playing music with wide dynamic range, MINIBOX Gold stills assures high output performance.