Used a Surface Pro 1 + Focusrite Scarlett 2i2 (1st gen) for measurements. Note, this is an incredibly modest rig, so don't expect AP-level results. Source is Soundaware D100 Pro into AES on Spring. Spring is mostly level 3 but doesn't have the upgrade PSU cap right up front, the silver wiring (does have silver transformer), or the better fuse. Balanced output and input, with 10dB XLR attenuator at input of 2i2. Otherwise signal gets too and distorts the ADC. Note that because I had to manually adjust the gain after, that could add noise or affect results, plus means channels won't be precisely matched. Similarly, -3dB on most tests for my strikes a good balance between being less likely to overload the DAC chip/module, less likely to overload the ADC, and still provides similar results to 0dB or -1dB signals. (If I'm too far out from baseline requirements, please move to unsanctioned sub-forum.) In this case, since the Spring has a hotter output than the Menuet, I had to raise the gain less on the ADC, which could contribute to the lower noise. You can find other Spring measurements with a professional measurement system on the Kitsune HiFi website. In a lot of cases, the Spring totally maxed out my ADC (a good thing! but better results are out there!). 1KHz Sine at -3dB, 16/48 1KHz Sine at -3dB, 16/48, 10Hz to 1KHz view 1KHz Sine at -3dB, 16/48, with ADC set to 96KHz for extended spectrum view 1KHz Sine at -60dB, 16/48 1KHz Sine at -90.31dB, 16/48 1KHz Sine at -90.31dB, 16/48 - Note the 3 discrete steps. A little noisy from the ADC, but looks good overall.
1KHz Sine at -90.31dB, 24/48 1KHz Sine at -90.31dB, 24/48 - Note the 24-bits leaves us with a relatively nice sine wave. Some noise from ADC. 1KHz Sine at -100dB, 24/96 - ADC wasn't really sure how to handle this one... Mostly noise, but you can still see the sine wave in there. Menuet looked similar. Cheap ADC can only go so far, but it's good to see this isn't total noisy garbage even still! 60Hz Sine at -3dB, 16/48 60Hz Sine at -3dB, 16/48, zoomed to show 10Hz to 1KHz Reserved
19KHz Sine at -3dB, 16/48 with ADC at 96KHz 13KHz and 14KHz Sines at -3dB, 16/48 with ADC at 96KHz 19KHz and 20KHz Sines at -3dB, 16/48 with ADC at 96KHz 250Hz and 9KHz Sines, 4-to-1 ratio, 16/48 Jitter (ARTA JTest) at 16/48 Jitter (ARTA JTest) at 24/48 - Probably maxed out my ADC
Again, please check out the other published measurements for the Spring at the Kitsune HiFi site. Clearly my ADC is the weak link here in most cases, but I can confidently say this is an overall excellent measuring, non-oversampling DAC. I clarify that NOS point because, as is true of most NOS DACs, distortion tends to creep up with higher frequency signals. Note the 19KHz sine or treble IMD tests. Still, this is a minor, and expected, blemish among otherwise excellent results and shouldn't discourage anyone. RMAA results available on request. PM me. Won't publish here. You'll need 6.4.1. Can offer a different baseline or be used to direct compare against the Menuet.
