I'm not trying to defend Alex Cavalli but the CTH does involve a tube which in my mind means automatically that it's not going to be perfect. Granted I'm no expert here, I have no idea what a tube amp should be doing in these measurements. Maybe a good tube amp would have less flaws than the CTH? Then again the flaws might be what people like about them. I have no idea, but I look forward to Amir testing more tube amps in the future. But regardless there is definitely something off with the design of the Carbon.
Per the CTH review:
"Massdrop
specs CTH at 0.0014% THD+N with this output. As you see, what I get is about
five times higher at 0.009%. SINAD which is our signal above noise and distortion is as a result a lackluster 80 dB. What you don't see is that the number was
jumping up and down constantly to tune of 3 dB or so.
Just as well, the significant amount of noise in the 1 kHz FFT on top right was changing in every frame displayed by my Audio Precision Analyzer. To the left, we see
significant amount of mains leakage which is most likely due to emissions mitigation in the switching external power supply used. "
I don't know to what extent that could be blamed on a tube. I understand what you're saying, but to me it looks like a poor design, especially with concern to the power supply management. SINAD jumping around is also strange. Tube warm up maybe? Or perhaps we could blame Massdrop on shoddy construction for their new product.
All I'm saying is it doesn't fill me with a lot of confidence in his designs coupled with the review of the Carbon... but they were both made by Massdrop as mi-fu pointed out, so it's something to consider. If the THX comes out bad, we might have to start pointing the finger in their direction.