Version: Firmware 13.1.3 + DOS 2.2.4 Date: 2019-02-12

[David A]

I've just found myself a way to blind test AIR v RAAT. I've named both zones SAME. The only way to identify now is by the symbol but I honestly don't know which is which. So I can change zones blindly to do a test and then decide which I like before identifying them by going into settings.

Pretty simple and pretty cool. 

Well, I've had a go. In my system, in my room, with my music and my ears, there's no difference between AIR and RAAT to be found. So I can't choose a favourite. I still have no idea which is which so I'm just going to enjoy some tunes. Who knows, I might have an epiphany and find there's some difference in long term listening. I would sincerely doubt it though.

So there you have it. No difference in measurements, no difference in subjective listening so the conclusion is that if you're hearing a difference, you have better ears than me. (Or a less reliable memory. Your choice )

It was suggested in another thread that I conduct a listening test with members of my audio club and I declined because of problems designing a process. The problem with changing zones like you did are as follows:

- you can't have both zones playing the same music at the same point so you can't swap in the middle of a track from one zone to another while the music continues so you're not doing a comparison with the same music. You could do the necessary swap with the same music if you could link the zones but you can only link Roon Ready zones and the AIR zone can't be linked to the RAAT zone so that rules that out.

- you have 2 zones using an ethernet connection to your amp current at the same time so you're not running the amp the way you would normally do. Normally you would only have one zone active. You've got twice the traffic on your ethernet connection and that could be doing things like increasing packet error rates and adding parasitic electronic noise to the amp's circuitry. These could be producing changes which mask the differences you're trying to hear. Ideally you'd be swapping disabling one zone and enabling the other every time you swapped zones, and swapping with the same music also so you're comparing performance with the same music, not comparing completely different tracks from different artists as shown in your screen shot.

- you say you don't know which zone is which because you gave them the same name. The icon gives it away. The speaker icon is the RAAT zone, the amp icon is the AIR zone. It/s a sighted test, not a blind test. That's not an issue for me but it is for a lot of people.

I''ve got no problem with someone not hearing a difference where I do hear one. I could have better hearing than you, then I might have a better imagination than you and we can't tell which is the truth. Or it could be that because you're swapping music when you swap zones, you can't tell whether there's a difference because of the differences in the music, Even swapping to different points in the same track isn't ideal and could lead to errors. I refused to do a test using your method, and a couple of other possible methods, because I could see the problems inherent in all of the methods I considered. If you had said you heard a difference using your method, I would criticise it in the same way and, as I said, I hear a difference. The problem with any listening test that I can think of which any of us can do at home is that whatever result we get, the other side can reject it because of problems with the test method. The best any of us can do is make comparisons any way we like and decide whether we think we hear a difference or not based on our experience and report it but when it comes to trying to prove we're right, I can't see any way at all of doing that at home.