US-4X4 SPECIFICATIONS: 

Sampling frequency     44.1k/48k/88.2k/96kHz
Quantization bit rate     16/24bit
Analog audio inputs      MIC IN       1-4
Connector     XLR-3-31(1:GND, 2:HOT, 3:COLD), BALANCED
Input impedance     2.2k ohms
Nominal input level      
GAIN:MAX     -65dBu (0.0004Vrms)
GAIN:MIN     -8dBu (0.3090Vrms)
Maximum input level
(GAIN:MIN )     +8dBu (1.9467Vrms)
Gain     57dB
INST IN    1-4
Connector     6.3mm(1/4")TS-jack(T：HOT, S：GND), UNBALANCED
(When set to "INST" at MIC/LINE.INST switch)
Input impedance     1M ohms
Nominal input level      
GAIN:MAX     -63dBV(0.0007Vrms)
GAIN:MIN     -6dBV(0.5015Vrms)
Maximum input level
(GAIN:MIN )     +10dBV(3.162Vrms)
Gain     57dB
LINE IN     IN 1-4
Connector     6.3mm(1/4")TRS-jack(T：HOT, R：COLD, S：GND), BALANCED
(When set to "MIC/LINE" at MIC/LINE.INST switch)
Input impedance     10k ohms
Nominal input level      
GAIN:MAX     -53dBu(0.0017Vrms)
GAIN:MIN     +4dBu(1.228Vrms)
Maximum input level
(GAIN:MIN )     +20dBu(7.75Vrms)
Gain     57dB
Analog audio outputs      
LINE OUT      
Connector     6.3mm(1/4")TRS-jack(T：HOT, R：COLD, S：GND), BALANCED
Output impedance     110ohms
Nominal output level     +4dBu (1.273Vrms)
Maximum output level     +20dBu (7.75Vrms)
PHONES      
Connector     6.3mm (1/4") stereo phone jack
Maximum output level    45mW+45mW or more
(THD+N 0.1% or less, 32ohms loaded)
MIDI IN/OUT       
Connector     Din 5-pin
Format     Standard MIDI format
USB      
Connector     USB B type 4-pin
Format     USB2.0 HIGH SPEED
Power            
When connected PC/When connected iOS       Dedicated AC adapter
(GPE248-120200-Z, included)
   
Power consumption         5W

Operating temperature     5 to 35˚C

Bundled software

Cakewalk SONAR X3 LE
Ableton Live 9 Lite
Accessories     USB cable, SONAR X3 LE license card, Live 9 Lite license card, User's manual, warranty card     AC adapter(GPE248-120200-Z), USB cable, SONAR X3 LE license card, Live 9 Lite license card, User's manual, warranty card

 
Audio performance
Frequency response      
LINE OUT(BALANCED)      
44.1k/48k Hz     20Hz to 20kHz, +0dB/-0.1dB
88.2k/96k Hz     20Hz to 40kHz, +0dB/-0.2dB
PHONES      
44.1k/48k Hz     20Hz to 20kHz, +0dB/-0.5dB
88.2k/96k Hz     20Hz to 40kHz, +0dB/-2dB
THD     0.003% or less
S/N ratio     101dB or more
Crosstalk     95dB or more
EIN     -127dBu or less

 Computer system requirements
Windows
OS     Windows 7(32-bit SP1, 64-bit SP1), Windows 8.0(32-bit, 64-bit), Windows 8.1(32-bit, 64-bit)

Compatible computers     Windows-compatible computer with a USB 2.0 port
CPU type/speed     Dual core/2 GHz or faster (x86)
Memory     2GB or more
DRIVER     ASIO2.0, WDM(MME)
Macintosh
OS     OS X Mountain Lion(10.8), OS X Mavericks(10.9)

Compatible computers     Apple Macintosh computer with a USB 2.0 port
CPU type/speed     Dual core/2 GHz or faster
Memory     2GB or more
DRIVER     Core Audio, Core MIDI