The most famous portable is probably the Sony Walkman.
Sony started selling them in 1980.


Modern portables don’t have any moving parts. The storage is an SD-card.
Often they are called MP3 players. Indeed the limited amount of storage almost forces one to use lossy compression like MP3 or AAC.

As SD-card increase their capacity, today you might go for lossless.
Hence you need a portable able to play formats like WAV and FLAC.
You also need a high quality DAC and headphone amp.

Iriver was the first to market a high-end portable, the Astell&Kern AK100.

If there are people willing to pay seven hundred for a portable, there must be people willing to pay even more.
An indeed during CES 2014 models well in excess of thousand dollar were introduced


Acoustic Research M2 PLAYER US$1,199.00


Isolated digital and analogue stages

Dual high precision crystal oscillators for dierent audio formats

Flagship class Burr-Brown PCM1794A DAC

Dual Burr-Brown OPA2134 current/voltage converter

High slew rate low distortion headphone amplifier


64GB built-in flash memory.


Supports WAV, AIFF, FLAC, ALAC, APE up to 32-bit 384kHz; DSD at 1-bit 2.8MHz or 5.6MHz


Added 2016

Astell&Kern AK100 € 699,00



Touchscreen: 2.4inch QVGA (320 x 240) IPS

Storage: 32GB of built-in, 2 slots for 32 GB SD-card

OS: Linux


DAC: Wolfson WM8740

THD + Noise: 0.0009%

SNR: 110dB



Input: Toslink

Added 1/2014

Astell&Kern AK240 US$2.400

Dual-mono CS4398 for a true balanced output

SN/R: 116dB

1-ohm output impedance

50ps clock jitter


24/192 PCM and native DSD128 support

File formats: WAV, FLAC, WMA, MP3, OGG, APE, AAC, ALAC, AIFF, DFF and DSF.


Storage: 256GB of flash memory / 128GB micro SD card

800x400 resolution 3.31" Amoled touch screen

OS: Android

3.5mm combo headfi/Toslink

2.5mm 4-pole balanced headfi port

mini USB for charging or PC/Mac USB DAC use.

Added 1/2014

Aurender Flow $1,295

No, this is not a thermostat. It is a portable DAC with a headphone amplifier.


Input USB 3.0 ( Audio Class 2.0)
Input2 SPDIF Optical
Output 1/4 inch/6.35mm Headphone Jack
Volume Control  -110dB ~ 0dB, Velocity Sensitive Operation
mSATA Slot Optional mSATA storage up to 1TB
Output Impedance 0.06 Ohm Max
THD+N Max -114dB
IMD(SMPTE) Max -112dB
SPDIF Mode(Optic) up to 24bit/192kHz
​PCM Mode(USB) up to 32bit/384kHz​
​DSD Mode(USB) ​DSD64, DSD128 / Dop Mode
​DAC Chip ESS9018K2M​
Play Time​ 7+ Hours​
Battery​ SAMSUNG SDI 4450 mAh​
​Weight ​450g(1.0 Pounds)
Output Power THD+N 0.0002%​
43 mW/600 ohms, 87 mW/300 ohms,
320 mW/60 ohms,
380 mW/32 ohms,
​THD+N  (1kHz 5.1V rms output) 0.0002%​
Dynamic Rage​ Max 122dB​
​Damping Factor >130​
Dimensions    ​ ​80 x 137 x 28 (mm)
3.1 x 5.4 x 1.1 (inches)



Added 1/2015

Calyx M $995



Display: 4.65" OLED 1280X720 (HD), Adjustable-Brightness

Core ProcessorCortex A5, 625MHzUI/UX

AudioFile Format : FLAC, WAV, DFF/DSF(64DSD and128DSD-DoP), DXD, AAC, MP3, MP4, M4A, OGG

Sampling Frequency (kHz) : 44.1, 88.2, 176.4, 352.8, 48, 96, 192 & 384

Bit Depth : 16,24 & 32


Output Voltage : 1.25V rms

Output Impedance : 3.3Ohm

Frequency Response : 20Hz~32kHz

THD+N : 0.0008%@1kHz at 32Ohm,

0.004%@1kHz at 16Ohm

Channel Separation : 130dB@1kHz

Dynamic Range : 114dB


Stand Alone USB-DAC

Compatible OS : Windows XP, Vista 7 & 8(32bit, 64bit), Mac OS 10.6+

Sample rates : Aysnchronous. 32/384. 128x DSD - DoP Memory


External Memory : upto 128G flash (SD-micro)

Internal Memory : 64G flash memory


USB: Micro

Wifi For Remote App from iOS and Android phones


Dimension134.60 X 69.16 x 14.50 mm (H/W/D)

Weight (160g, TBA)

Added 1/2014

Chord Mojo + Poly


The Mojo is a portable headphone amp.

Add the Poly and you have a complete streaming solution.

Roon, DNLA, Airplay, and Bluetooth playback.

You can also play local from a micro SD card.

Added 2016

FiiO X7 US$769.00


Android powered portable with ESS ES9018S DAC with swappable headphone amp.

Can be used as a USB DAC.



Audio Formats Supported

APE FAST/High/Normal:384kHz/24bit(MAX)
APE Extra High:192kHz/24bit(MAX)
APE Insane:48kHz/24bit(MAX)
Apple Lossless:384kHz/24bit(MAX)


Lossy Compression:




Added 2016

LG V10 US$ 790

Not a portable audio player but a smartphone.

One that comes with a ESS Sabre 9018 DAC and a ESS 9602 headphone amp.

Memory: internal 64 GB, external microSD (up to 2 TB is supported)

Makes you wonder if you need a hi-end portable at all.


A review can be found here.

Added 2015

Onkyo DP-X1 US$ 899.99


The double ESS Sabre ES9018K2M DACs and double ESS Sabre 9601K amps make balanced output possible via 2x 2.5 mm output.


11.2MHz DSD, up to 384kHz/24-bit PCM audio, with support for WAV, FLAC, ALAC, & AIFF.


dual micro-SDXC card slots


Added 2016

Questyle Audio QP1R US$ 899

  • Patented "Current Mode Amplification" in headphone AMP, all discrete components, Pure Class A circuit.

  • File Format Support:WAV, FLAC, ALAC, APE, AIFF, ADPCM, LPCM, MP3,

    WMA,WMA Lossless, OGG, AAC, DFF, DSF

  • Sample Rate:

    PCM Native: 44.1 kHz - 192 kHz(16bit/24bit)

    DSD Native: DSD64(1bit 2.8MHz)/DSD128(1bit 5.6MHz)

  • DAC:Cirrus Logic CS4398

  • Output:3.5MM headphone output, 3.5MM line out & optical output 

  • Frequency Response: 20Hz-20 kHz(±0.1dB)

  • QP1  THD+N= 0.0015%

  • QP1 R THD+N = 0.0006%

  • Output Impedance :

    QP1: 0.19Ω 

    QP1R: 0.15Ω 

  • Memory:

    Internal: 16GB(QP1)/32GB(QP1R),

    External: supports Micro SD card 2*128GB

  • Battery:3300mAh Li-polymer, 8-10 hours



Added 2015