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UHA-6S.MKII USB DAC/Amp with TOSLINK Optical and Digital Coax Inputs

UHA-6S.MKII USB DAC/Amp with TOSLINK Optical and Digital Coax Inputs

from $239.00

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Processing time: 1-3 business days

Features:

- USB, optical, digital coaxial, and analog inputs
- High-performance Cirrus Logic CS4398 DAC chip
- Low-noise and low-distortion amplifier output
- Analog volume control
- Rechargeable battery with charge disable control
- Works with Mac, PC, iOS, and Android
- 30-day audition period and 2-year warranty

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Connect to any music source.

With four types of inputs, you can connect the UHA-6S.MKII to just about any analog or digital music source out there. Take advantage of the integrated, high-performance digital-to-analog converter and stream digital audio directly from your computer, compatible iOS or Android device, or digital audio player. Or connect the UHA-6S.MKII to the line output or headphone output of your device and use it as a standalone amplifier.

Take it with you.

The UHA-6S.MKII is small, lightweight, and highly portable. The rechargeable battery provides up to 30 hours of runtime with analog sources and up to 10 hours of runtime with USB or digital sources. With USB charging enabled, you can power the UHA-6S.MKII and listen to music simultaneously. Disable USB charging, and the UHA-6S.MKII uses only its internal battery for power, allowing you to connect to mobile devices which limit USB power draw.

Customize your sound.

The UHA-6S.MKII uses socketed op-amp chips in the output amplifier circuit. Different chips can have subtle differences in sound quality. We recommend the AD8610 as the best all-around choice (or the AD8620 for best performance with low-impedance headphones). If you like to tinker with your electronics, you can experiment by swapping in different op-amps to find the sound signature that best suits your tastes.

 

Compatibility

iPhone

Supports digital interface over USB (requires Apple Lightning to USB Camera Adapter). Supports analog connection from headphone output or line out dock (LOD) to line input. Requires iPhone 4S or newer, iOS 7 or later.

iPad

Supports digital interface over USB on all models (requires the Apple Lightning to USB Camera Adapter or 30-pin Camera Connection Kit). Supports analog connection from headphone output or line out dock (LOD) to line input.

iPod Touch

Supports digital interface over USB (Apple Lightning to USB Camera Adapter). Supports analog connection from headphone output or line out dock (LOD) to line input. USB digital interface is not supported on earlier models. Requires iPod Touch 5th generation or newer, iOS 7 or later.

Android

Supports digital interface over USB (requires OS support for USB Audio Class 1.0). Supports analog connection from headphone output to line input.

Mac

Supports USB digital interface with sample rates up to 48kHz/16-bit using built-in operating system drivers (USB Audio Class 1.0). Supports TOSLINK or digital coax interface with sample rates up to 96kHz/24-bit.

Windows

Supports USB digital interface with sample rates up to 48kHz/16-bit using built-in operating system drivers (USB Audio Class 1.0). Supports TOSLINK or digital coax interface with sample rates up to 96kHz/24-bit.

 

Choosing Output Op-amps

The op-amp is the amplifier chip. The recommended chip is the AD8610. It gives best overall performance and battery life for all types of headphones. For headphones with impedance less than 100 ohms, the AD8620 provides higher output power and lower distortion with the trade-off of lower battery life.

If you're interested in an op-amp configuration other than the AD8610 or AD8620, contact us and let us know what you're looking for.

For more information, take a look at these blog posts:
Choosing Output Op-Amps
New dual-to-single op-amp adapter provides high-performance upgrade for UHA-6S.MKII

 

Specifications

Inputs

Analog (stereo 3.5 mm), Micro USB, TOSLINK Optical, Digital Coax

Gain

Low-gain setting: +0 dB at full volume setting

High-gain setting: +18 dB at full volume setting

Volume Control

Analog

Sample Rate

USB: Up to 48kHz/16-bit

TOSLINK/Coax: Up to 96kHz/24-bit (PCM, unencoded)

DAC Chip

Cirrus Logic CS4398

Max Output Power, AD8610 Op-Amp

16 ohms: 25 mW

32 ohms: 55 mW

62 ohms: 90 mW

100 ohms: 90 mW

300 ohms: 40 mW

(Measurement conditions: Analog input at 1 kHz, output <1% THD)

Max Output Power, AD8620 Op-Amp

16 ohms: 80 mW

32 ohms: 140 mW

62 ohms: 120 mW

100 ohms: 90 mW

300 ohms: 40 mW

(Measurement conditions: Analog input at 1 kHz, output <1% THD)

THD+N

16 ohms: 0.0033% at 1 mW, 0.0045% at 10 mW

32 ohms: 0.0018% at 1 mW, 0.0022% at 10 mW

62 ohms: 0.0012% at 1 mW, 0.0014% at 10 mW, 0.022% at 50 mW

100 ohms: 0.0010% at 1 mW, 0.0011% at 10 mW, 0.012% at 50 mW

300 ohms: 0.0008% at 1 mW, 0.0023% at 10 mW

(Measurement conditions: Analog input at 1 kHz, 20 Hz to 20 kHz bandwidth, no weighting)

Frequency Response, Analog Input

<3 Hz to 45 kHz, ±1.0 dB

5 Hz to 28 kHz, ±0.1 dB

Frequency Response, USB Input

<3 Hz to 21 kHz, ±1.0 dB

5 Hz to 21 kHz, ±0.1 dB

(Measurement condition: 44.1 kHz sample rate)

Frequency Response, TOSLINK Input

<3 Hz to 45 kHz, ±1.0 dB

5 Hz to 28 kHz, ±0.1 dB

(Measurement condition: 96 kHz sample rate)

Output Op-Amps

Standard: Analog Devices AD8610 (Socketed and replaceable, 8-pin DIP)

Internal Power Supply

±6 V, ground-centered, switching converter + low-pass filter

Battery life

Analog input: Up to 30 hours

USB Input (charging disabled): Up to 10 hours

Output Impedance

<0.5 ohm

Enclosure

Two-piece extruded aluminum body, machined aluminum end panels, scratch-resistant laser engraving

Dimensions

2.8 x 4.2 x 0.8 inches (70 x 106 x 20 mm)

Weight

6.0 oz (170 g)

Performance specifications given for standard AD8610 op-amp unless otherwise noted.

Included in the Box

- UHA-6S.MKII DAC+Amp
- Micro USB cable, 3 feet (1 meter), with velcro cable tie
- Velvet carrying pouch
- Self-adhesive rubber feet
- Self-adhesive Velcro dots

User Guide