[HiFan]

Ethan's video on null tester is interesting.

I did a Spice sim using the null control he showed in his video and audioexpress writing, the circled part is his actual circuit.

And my spice on it...

Interestingly, it seems his "null control" itself can artificially hide a 0.005V difference, which is -43 dBu before he send it to the 80dB gain stage. This number can be worse if you ware willing to spend more time on it.

Just look at voltage across R22...

So I think his circuit is fundamentally flawed and failed in proving his claim.

Love to see your feedback.

PS. I don't know him well or felt he ever did anything to me. It is just funny he has a huge fan base in "science review" circle.

 

[gregorio]

[1] Interestingly, it seems his "null control" itself can artificially hide a 0.005V difference, which is -43 dBu before he send it to the 80dB gain stage. This number can be worse if you ware willing to spend more time on it. Just look at voltage across R22...
[2] So I think his circuit is fundamentally flawed and failed in proving his claim.
[3] It is just funny he has a huge fan base in "science review" circle.

1. I would be surprised if Ethan had not thoroughly tested and had completely overlooked the flaw you think you've identified but let's, for argument sake, assume that he has and therefore his unit is flawed:

2. If it were actually HIS claim AND, if that claim was based solely on his "null control" unit (which we are assuming is flawed), then "yes", it would indeed fail to prove the claim. However, neither of these conditions are true, let alone both: Firstly, it's not really HIS claim, Ethan is just repeating a claim made by numerous other engineers and scientists over the course of many decades. Secondly, Null Testing is quite common among sound engineers, there are a number of different methods/ways of performing a Null Test and very few use Ethan's box/circuit.

3. It's not funny, it's justified. He has a fan base not because he's a cutting edge scientist or engineer who invents/develops "claims" but because he's a respected professional who's willing to participate in consumer forums, "spread the word" of existing science/facts and address/interact with audiophiles. The vast majority of professional engineers can't or won't do this, either because it could impact their employment or they won't, because the vast majority of professional engineers view the audiophile world as essentially a bunch of lunatics, with such strongly held beliefs (based on decades of false marketing/reviews/etc.) that the actual science/facts have no impact and therefore rational discourse is typically impossible and virtually always futile. So, they simply avoid contact with the audiophile community and just roll their eyes at it's mention! Unfortunately though, that just results in the false marketing/audiophiles claims going pretty much unchallenged, except for the one or two like Ethan.

G