#9038D
According to multiple headfiers requests: 3.5mm jack unbalanced output DAC+HPA 180mW@32ohm in the same case as #9038SG3. The same as 9038SG3, 9038D will work with Tweak app. The DAC has virtually zero noise modulation behavior.
Specifications(TBD):
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Status: production
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Materials: sandblasted/black anodized aluminum/laser mark/ES9038Q2M/OPA1622/OPA1602
Susumu resistors, Murata C0G caps, AVX tantalum caps, Taiwanese connectors
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Dimensions: 48x22x9mm
Weight: 12g
Power: USB +5V rail no internal battery, 95mA idle current, the device contains >4000uF of capacitance for the power rails filtering
Note: 9038D6K 6000uF 105mA idle current
Input: USB-C, PCM up to 32b/384kHz, DSD256
USB bridge Comtrue CT7601CR custom FW
Output: standard unbalanced output 3.5mm jack, HW volume control .5db/step
Output impedance: .07 Ohm@1000Hz Agilent U1733C
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Output power: 180mW@32 Ohm@1kHz@THD=1%
120mW@16 Ohm@1kHz@THD=1%
measured at +.5dbFS level, typical PC USB2 port powered
the hot unit produces less power
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Frequency response: 5-80kHz +.05/-1db@ 32b/384kHz
SNR=DR@50MHz_MCLK: 125db(A) typical, referenced to 2.75VRMS
from the second batch 100% units are calibrated with the result printed on the case, >123db(A) is normal grade
Note: 9038D6K 126db(A); units are individually calibrated, see the result printed on the case. >124db(A) is a normal grade. Please note, any user with Cosmos APU may calibrate 9038D by themself for particular headphones.
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THD+N@1kHz@-.5dbFS BW 22-22kHz .00014%, SINAD 117db typical for 24b/44.1kHz@no-load
Note: 9038D6K a typical SINAD 118-120db+
THD@1kHz@-.5dbFS BW 22-22kHz <.0001% typical for 24b/44.1kHz@no-load
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THD+N@1kHz@-2.5dbFS BW 22-22kHz .00018%, SINAD 115db typical 24b/44.1kHz@32ohm
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THD+N@1kHz@-7dbFS BW 22-22kHz .0005% typical for 24b/44.1kHz@16ohm(-6dbfs correspods 120mW)
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Crosstalk: -135db@1kHz no-load, -82db@1kHz 32ohm load
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After ios17 the compatibility Android vs ios was broken, and our DACs flashed for Android need to reflash for ios17_FW if you gonna use ios-devices. The tutorial is here.
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Warning: 9038D contains a high-sensitive I/V stage that may cause audible noise when your phone uses LTE 4G, 5g.
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Tech appendix
Conventional PC USB2 port, 10Kohm vs 32ohm loads THD+N
THD+N or SINAD at -0.3dbfs the data gathered from two samples, about 2.7VRMS no-load
THD+N or SINAD at -0.3dbfs the data gathered from two samples, about 2.7VRMS no-load
Conventional PC USB2 port, 10Kohm load THD+N vs time
Conventional PC USB2 port, 32ohm load THD+N vs time
Conventional PC USB2 port, AES17 Dynamic Range A-weighted vs time
Frequency response PCM384 Slow Lin. Phase filter 10-40000Hz at -0.2db
Nearly ideal square wave 1kHz PCM384 Slow Lin.Phase filter at 200MHz BW scope
Square wave 1kHz PCM192 Slow Lin.Phase filter at 200MHz BW scope
Square wave 1kHz PCM96 Slow Lin.Phase filter at 200MHz BW scope
Square wave 1kHz PCM44.1 Slow Lin.Phase filter at 200MHz BW scope
24b/44.1kHz 1kHz -0.5dbfs FFT no load
24b/44.1kHz 1kHz -2dbfs 150mW FFT 32ohm load
24b/44.1kHz 1kHz -2dbfs 40mW FFT 32ohm load
24b/48kHz 12kHz -2dbfs FFT no load