Weird problem noticed last several playings...


The system: CJ PV-10AR preamp, Emotiva XPA-2 Gen3 amplifier, Yamaha BD-1060 Disc Player, Bluesound Node 2i streamer, Maggie 17i speakers,  2 Emotiva BasX10 subs. 

Fairly suddenly , over last several listenings - especially with the female background vocals on "California Dreaming" there a lack of detail, a muffled sound, and it sounds like much of the detail, punch and soundstage has disappeared on all sources. 

I am hoping (even though they are only a couple years old) it's one of the CJ tubes but does anyone have any diagnostic ideas (aside from "your system sucks, replace this or that. This is particularly galling as I have been a budget audiophile for 40yrs and the system, when right, sounds amazing and just what I want.) 
jkf011
I'm guessing that the CJ PV10 uses 6DJ8/6922 triodes. And a SS rectifier. A good recommendation is USA - made Amperex, GE and Sylvania. Philips from Europe are also good! Avoid any present day ones (JJ, Sovtek and other Russian, Ch*nese).

My theater system sounded just like that (playing two channel music), years back, when one of my Maggie MG12, tweeter sections failed.     Have you checked the 1.7i fuses?
Yup. There is high end on both speakers but mid-range background vocals, guitars sound muffled. Everything sounds sqiushy and no punch. 
CJ is very adamant to only buy tubes from them as they have tested and selected what they think best. I am going to call them today.
If this was a tube or speaker issue it is rare they all fail at the same time.

Swapping speakers, or tubes should help diagnose, but if the problem is systemic, it's possible the regulator on the PV 10 has failed, or one of the cascaded diodes has. 
I like the PV 10, but the thing the later generations did well was to split up the voltage regulator into multiple sections so the chances of one regulator failing was rarer, not to mention offering better power supply isolation.