Subjective PerformanceIn the audio hardware department, EVGA spared no expense with the NU Audio sound card. The component list is quite impressive: the digital-to-analog conversion is done by the AKM AK4493EQ, Ashai Kasei Microdevices' flagship DAC capable of 32-bit/384 kHz PCM playback. It will also do up to 11.29 MHz native DSD256 playback. It's the same DAC as in some higher-quality external DAC/amps, such as the $480 Monoprice Monolith. The AK4493EQ DAC then feeds the converted audio signal to a fully balanced linear phase low pass filter formed by TI LME49724 fully differential amplifiers, Audio Note resistors, and high quality WIMA, Nichicon, and Panasonic FC capacitors. The balanced signal is fed to the line stage made up of an ADI AD8056 dual op-amp. The headphone amplifier consists of an ADI OP275 dual op-amp combined with two TI LME49600 power buffer ICs. Both op-amps are seated in their respective IC sockets (U613 for line-out and U564 for headphone out) and "op-amp rolling" is fully supported. Meaning, if you have a preference for some other combination of op-amps and think they can do a better job than the ones picked by Audio Note, there's nothing stopping you from unscrewing the metal shield from the card and replacing those op-amps with others ones—just be extremely careful of what you plug in where. The specified SNR for stereo playback equals 123 dB (121 dB for line-in recording).
To test the audio performance of the EVGA NU Audio sound card and get a good perspective on it, I gathered some of my headphones, speakers, and DAC/amps and conducted over 150 hours of A-B testing in music (hi-res FLAC files, Tidal, Spotify, Deezer), movies (Netflix and HBO GO), and games (Battlefield V, Apex Legends, Mass Effect 3 and Forza Horizon 4, to name a few). Here's a list of the gear I used in my tests and comparisons.
- Sennheiser HD 660 S
- HiFiMan HE4XX
- Oppo PM-3
- Sony WH-1000XM2
- Beyerdynamic DT 990 (600 Ω Edition)
- Philips Fidelio X2
- Shure SRH840
- Audiolab M-DAC
- Denon PMA-60
- Audioquest DragonFly Red
- NAD D 3020 V2
- FiiO E10K
- Integrated sound card (Asus ROG SupremeFX S1220)
It's not all about the power, though. The sound produced by the EVGA NU Audio is crystal clear even at very high volumes, with rich dynamics, a great balance of depth and bite, and wonderful musicality. When the sound card is combined with a good pair of headphones, you're in for a real treat. But there's hope even if your headphones of choice are lacking in some department because of he 10-band equalizer offered within the NU Audio software driver. The equalizer is handled by the xMOS xCORE-200 DSP. One particular pair of headphones I own, the Massdrop-exclusive HiFiMan HE4XX, are excellent in almost every regard, but they don't go as low or hit as hard in the bass region as I'd like. At the same time, their planar magnetic drivers respond very well to equalization; it's very hard to get them to distort regardless of what you do with the equalizer. Thanks to that, the EVGA NU Audio allowed me to permanently tune those headphones to my liking, effectively giving me an even better pair of headphones I now enjoy using even more.
As far as I'm concerned, in terms of sound output quality, the EVGA NU Audio is a true hi-fi product. Many audiophiles won't be all too eager to accept that given its PCIe-card form factor, but that doesn't change the fact that it performs better than many established and well-liked external DAC/amps.
RMAA MeasurementsI did a simple loopback test with Rightmark Audio Analyzer 6.4.5, a nice piece of software that can be used to get various measurements of the frequency response, noise level, dynamic range, total harmonic distortion (THD), stereo crosstalk between channels, and so on. A loopback test is when you feed the line input of the sound card with its own output signal instead of using an external signal generator. I took measurements of both the headphone and line (speaker) outputs of the EVGA NU Audio with 24-bit/48 kHz, 24-bit/96 kHz, and 24-bit/192 kHz sample rates. To keep things concise, I'll only show the 24-bit/192 kHz tests in this review. I'd be happy to share the full 24-bit/48 kHz and 24-bit/96 kHz test reports with anyone who's interested in them, so please don't hesitate to ask for them in the comment section!
Headphone Output (24-bit/192 kHz)
|EVGA NU Audio Headphone Output RMAA 6.4.5 Measurements|
|Frequency Response (40 Hz to 15 kHz, dB)||+0.00, -0.12||Excellent|
|Noise Level, dB (A)||-106.4||Excellent|
|Dynamic Range, dB (A)||106.7||Excellent|
|THD + Noise, dB (A)||-95.5||Excellent|
|IMD + Noise, %||0.00231||Excellent|
|Stereo Crosstalk, dB||-100.0||Excellent|
|IMD at 10 kHz, %||0.00280||Excellent|
Line Output (24-bit/192 kHz)
|EVGA NU Audio Line Output RMAA 6.4.5 Measurements|
|Frequency Response (40 Hz to 15 kHz, dB)||+0.01, -0.10||Excellent|
|Noise Level, dB (A)||-107.3||Excellent|
|Dynamic Range, dB (A)||107.4||Excellent|
|THD + Noise, dB (A)||-98.8||Excellent|
|IMD + Noise, %||0.00134||Excellent|
|IMD at 10 kHz, %||0.00129||Excellent|