Lately, maybe the last two months, when listening to (2ch) CD music titles via-"Analog Bypass" thru my NAD T175 surround processor and Parasound Halo A51 it seems there is noticeably more "sibilance" present. Almost dirty-like distortion, especially noticeable when listening to female voices and when things get busy.
I guess this "raspiness" must be in the upper mid-range or higher. Really does bother me lately. Wonder if there are issues with my mid-range/tweeter modules with my Montior Audio GS-60 speakers? Or whether a component is flaking out in my A51 or NAD T175? Or maybe the CD sources themselves?
This sibilance seems to be present from both front speakers (GS-60's). Although overall dynamics are good. Also playing movie sources via-HDMI (with Audyssey) seem to be clean and dynamic (I'll have to play closer attention).
One thing, the weather (here in L.A.) has been scorching hot these last few weeks. I have no air-conditioning, When I come home after work my home interior must be literally 95 degrees, I turn on ceiling fans. After an hour or so I play some music for maybe an hour or two. I've never experience any over-heating indicators on my Halo A51 ever. I have it sitting on top of my rack, out in the open.
For example, been listening to the new Whitney Houston CD "I Look To You", some of the vocal arrangement really song raspy. Maybe the recording? I don't know.