Hey BCH, they line up well - about the same as any Icom or Yaesu in this test, using calibrated signal generators. And if you want to change the levels, you can set them in the engineering menu (S1, S3, S5, S7, S9, S9+) but you need the equipment to do this. I always like my radios to be -73dBm for S9 (not -67dBm like some use), so I always give them a tweak if it's needed.
I see the noise floor topic is still ongoing. IMO, some key points are::
- I have a AT-5555Nii and a CRT SS-7900V here. Both of them will show and S1, and even lower on a quiet band, when connected to either a 3el Yagi or a 5/8 vertical.
I am in a quiet RF environment and the S meter performance is near perfect here. I have had a few other AT-5555Nii's here on the bench and they have all been the same. No issue.
-So, if you live in a more common noisy RF environment, and you see a higher S meter noise floor reading, please remember that regardless of the S meter "noise floor" you see, it is the Signal to Noise Ratio (SNR) that matters. i.e, What you can actually "hear"... If you put the AT-5555Nii up against almost any of the old school rigs (or even the "new" ones made by Ranger) under normal conditions, even IF these other rigs show an S1, and the AT-5555Nii shows an S3 or S5, you will still usually hear more, and better, on the AT-5555Nii. I can test this on my equipment, and on the air with different radios side by side. I find the AT-5555Nii wins every time. You hear more and it just sounds better
I actually had a mint Uniden Grant XL next to my AT-5555Nii the other day. I love the XL, but when doing some A/B tests side by side on the air I was actually shocked how much better the AT-5555Nii was hearing on a very busy band.
73