I was looking for a USB sound card (aka audio interface) that had decent THD measurements for low frequencies. The Steinberg UR22mkII seem to beat the competition when I tested it in REW against the other interfaces listed below. I chose the three I tested because they were all locally available at Guitar Center or Best Buy.
Comparing:
1. M-Audio M-Track Plus
2. Presonus AudioBox iTwo
3. Steinberg UR22mkII
Test procedure:
1. Set mix knobs to playback/USB/DAW (e.g. ensure they are NOT set to input so as to prevent oscillating/unstable loop back test).
2. Set mic input to middle (when possible unless there was some oscillations, then slightly adjusted output volume and mic input until loop back measurement was stable as pictured above)
3. Ensured +48V was turned on (since I plan to use it), although no current should be flowing in the circuit since I'm using an XLR->phono cable for the test. The phono end was plugged into Output Left (1), XLR end into the left (1) mic input.
4. Updated firmware and downloaded the latest driver for each card
5. Disabled all enhancements under Windows 10 sound settings.
6. Opened the individual sound cards toolbox/application and set it for 48kHz or 96kHz and 512 samples and set the REW ASIO setting to match the sampling frequency.
7. Used ASIO4ALL driver for the test (since I plan to use the USB audio interface with HDMI loop back), but left the default ASIO4ALL latency settings (32 in/32 out)
8. Adjusted volume so that input was between -23-24dB, while leaving the mic knob in middle (final volume settings are as pictured).
9. Did 48kHz and 96kHz calibration tests for each USB audio interface.
Results:
Please take a look at the REW file on my google drive. The Steinberg UR22mkII seems to be of much better quality than the other three, especially in low frequency flatness and noise level. I plan to keep the Steinberg and return the other two, but I'm open to suggestions here.
Please only recommend great interfaces that are less than $350 new and can be purchased at BH Photo, Best Buy or Guitar Center. I do want the lowest noise floor possible (for under $350). I'm only concerned with cards that work with Windows 10 and below.
I'm really glad I tested the AudioBox iTwo I bought from Best Buy. Had no idea how much better cleaner the mic input could be (for the low-end) until I tested it against the Steinberg UR22mkII.
REW File:
https://drive.google.com/open?id=0B1J0a4OV_WGLOExseVpzczRPWVE
Top Result:
Steinberg UR22mkII, 96kHz
Sample rate: 96000 Hz
-3 dB points: 4.8 Hz, 48.000 kHz
Input device: ASIO4ALL v2
Input: 1: Steinberg UR22mkII 1
Channel: Left
Input volume: no control
Input RMS target: -12.0 dB
Actual RMS at 1 kHz: -23.6 dB
Output device: ASIO4ALL v2
Output: 1: Steinberg UR22mkII 1
Sweep level: -12.0 dB
20 Hz .. 20 kHz flatness: +0.2, -0.3 dB
Steinberg UR22mkII, 48kHz, 512 samples
Sample rate: 48000 Hz
-3 dB points: 4.4 Hz, 24.000 kHz
Input device: ASIO4ALL v2
Input: 1: Steinberg UR22mkII 1
Channel: Left
Input volume: no control
Input RMS target: -12.0 dB
Actual RMS at 1 kHz: -23.1 dB
Output device: ASIO4ALL v2
Output: 1: Steinberg UR22mkII 1
Sweep level: -12.0 dB
20 Hz .. 20 kHz flatness: +0.0, -0.2 dB
Comparing:
1. M-Audio M-Track Plus
2. Presonus AudioBox iTwo
3. Steinberg UR22mkII
Test procedure:
1. Set mix knobs to playback/USB/DAW (e.g. ensure they are NOT set to input so as to prevent oscillating/unstable loop back test).
2. Set mic input to middle (when possible unless there was some oscillations, then slightly adjusted output volume and mic input until loop back measurement was stable as pictured above)
3. Ensured +48V was turned on (since I plan to use it), although no current should be flowing in the circuit since I'm using an XLR->phono cable for the test. The phono end was plugged into Output Left (1), XLR end into the left (1) mic input.
4. Updated firmware and downloaded the latest driver for each card
5. Disabled all enhancements under Windows 10 sound settings.
6. Opened the individual sound cards toolbox/application and set it for 48kHz or 96kHz and 512 samples and set the REW ASIO setting to match the sampling frequency.
7. Used ASIO4ALL driver for the test (since I plan to use the USB audio interface with HDMI loop back), but left the default ASIO4ALL latency settings (32 in/32 out)
8. Adjusted volume so that input was between -23-24dB, while leaving the mic knob in middle (final volume settings are as pictured).
9. Did 48kHz and 96kHz calibration tests for each USB audio interface.
Results:
Please take a look at the REW file on my google drive. The Steinberg UR22mkII seems to be of much better quality than the other three, especially in low frequency flatness and noise level. I plan to keep the Steinberg and return the other two, but I'm open to suggestions here.
Please only recommend great interfaces that are less than $350 new and can be purchased at BH Photo, Best Buy or Guitar Center. I do want the lowest noise floor possible (for under $350). I'm only concerned with cards that work with Windows 10 and below.
I'm really glad I tested the AudioBox iTwo I bought from Best Buy. Had no idea how much better cleaner the mic input could be (for the low-end) until I tested it against the Steinberg UR22mkII.
REW File:
https://drive.google.com/open?id=0B1J0a4OV_WGLOExseVpzczRPWVE
Top Result:
Steinberg UR22mkII, 96kHz
Sample rate: 96000 Hz
-3 dB points: 4.8 Hz, 48.000 kHz
Input device: ASIO4ALL v2
Input: 1: Steinberg UR22mkII 1
Channel: Left
Input volume: no control
Input RMS target: -12.0 dB
Actual RMS at 1 kHz: -23.6 dB
Output device: ASIO4ALL v2
Output: 1: Steinberg UR22mkII 1
Sweep level: -12.0 dB
20 Hz .. 20 kHz flatness: +0.2, -0.3 dB
Steinberg UR22mkII, 48kHz, 512 samples
Sample rate: 48000 Hz
-3 dB points: 4.4 Hz, 24.000 kHz
Input device: ASIO4ALL v2
Input: 1: Steinberg UR22mkII 1
Channel: Left
Input volume: no control
Input RMS target: -12.0 dB
Actual RMS at 1 kHz: -23.1 dB
Output device: ASIO4ALL v2
Output: 1: Steinberg UR22mkII 1
Sweep level: -12.0 dB
20 Hz .. 20 kHz flatness: +0.0, -0.2 dB