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Unfortunately, the load for the headphone amp is not specified. 88dB (6.35mm output) might be fine for 32 ohms, but definitely not for 300 ohms. This also only applies to 1 kHz. A frequency sweep would be much more useful, since crosstalk usually increases with higher frequencies. But then...

@amirm Is there any chance you measure channel crosstalk on the headphone output (300 Ohm, both directions, frequency sweep)? I would really appreciate it.

@amirm There's a typo "XLR Out" in the unbalanced dashboard.

Can someone tell me whether or not this device works on Windows 10 64-bit with WASAPI exclusive mode (event-driven), a sampling frequency of 96kHz and a bit depth of 24 or 32? Thanks.

@amirm In case you forgot, can you measure IMD, linearity, and reconstruction filter?

OK, thank you.

@amirm So is it safe to say that with a 300 Ohm load this "anomaly" on the "bad" channel disappears with High Performance mode turned off? This anomaly keeps me from buying this device, especially since my only use case is listening through headphones (via a Sennheiser HD 800 S, which happens...

@IVX I'm very interested in the ultrasonic noise of the SMPS and how it affects the I/V stage. You say the noise is at 1.5 MHz with a level of about 3mV. Since you have an AP, could you make a high bandwidth measurement just to see the actual impact (if any) on the output?

@amirm With about 8.9 mV and 300 Ohm the power is about 0.26 µW and (according to your original power vs. distortion graph above) the "good" channel should have about 65 dB THD+N. But your new measurement now says it's actually much better at 72 dB (just as good as the reference Topping DX3Pro...

OK, let me clarify: In my first post #148 about this issue, I made a mistake and wrote 0.5mV instead of 0.5mW. I actually meant watts (for power). In my post #162 I corrected this. Sorry if this typo confused you. Now, if I look at the graph in my post #253 then I see that the curve for...

I feel the urge to ask again because I don't have an answer yet: why this anomaly on Ch2 below 0.5mW? The sudden difference between the two channels is a whopping 10dB. IVX explained the reason for the general channel imbalance (additional noise in only one channel due to the placement of the...

Does the ultrasonic noise from this device stay within legal limits when it drives Amir's AP inputs crazy?

If the outputs of this device drive Amir's AP inputs crazy, what could happen to a headphone then? Is there any guarantee that the ultrasonic noise will not damage the headphone's coils? AFAIK, headphones do not have an input filter. In my opinion, Amir's right: potentially harmful ultrasonics...

@Veri Yes, I would, but only if it makes sense to me. It doesn't make sense to me to group five replies on five different topics addressed to four different people. Usually, I'm here only once a day and therefore cannot spread my posts over the day. Let me know if this is against any rule on...

Yes, but practically no imbalance and certainly no anomaly in THD+N vs. power at 300 Ohm.

@IVX Thanks for these internal details, much appreciated. Does it also explain the anomaly in THD+N sweep on one channel when measuring with load (e.g. 300 Ohm, my Sennheiser HD 800 S)?

So am I. It should not be there.

@amirm I don't. You mentioned the possibility of problematic ultrasonic noise. As a result, I was asking for a measurement just to see if there really is ultrasonic noise.

@staticV3 The graph you probably refer to shows THD+N vs. output level with no load. No load has no anomaly, as Amir's measurement already shows. The problem (if there really is one) seems to be THD+N vs. output power, that is, with load, that is, with current.

@amirm I think this is an important point. Could you please measure for ultrasonic noise on both channels? I think your AP can measure up to 1MHz (at least), right?