Veiled 'wet blanket' sound from tweeters


Is it my speakers or my amp?

My gear consists of B&W PM1 with Rotel Integrated RA-1570.  

I'm experiencing a lack of detail and separation from the speakers , specifically at the tweeter source.   Switching between headphones (Grado RS1) and speakers, it is like there is a heavy blanket covering the tweeters.  Midrange/bass is fine.

Switching sources between DAC/Turntable yeilds no difference.

I'm actually wondering if the crossovers have been damaged.   

I don't really have the luxury of switching components.  Any ideas on what my next steps should be?




gmckay1960
Another possibility is bad ferrofluid fluid in the tweeters. I had that problem with my B&W P5 set after about 10 years. The condition you described is very similar to my experience. I had output, but it was extremely limited causing the speakers to sound lifeless. 
I removed my tweeters from the cabinet, then lifted the diaphragm gently off. I used some alcohol to clean out the old fluid that had hardened, then replaced some fresh fluid from Parts Express. That brought them back to life again. 
Good luck!
+1 nicemix

Only caveat is that it is my understanding that some tweeters are harder to pull the diaphragm than others.  If difficult, suggest you call Bill at Millersound.  
PM-1s are very low efficiency mini-monitors with only 84dB sensitivity.  The RA 1570 has 120 wpc...enough for a small room at medium volume with no clipping....but if you get carried away and overdrive tha amp you can damage the tweeter or crossover resistor.  I don't believe there are any fuses or protective circuits, and the network is said to be a simple LCR with top quality components.  If the level is way down I'd suspect that resistor.