[MLGrado]

I just purchased an Icon Stereo 20PP tube integrated with headphone output.  It was a demo model, so I am unaware of how many hours are on the tubes.  I also know very little about the stock tubes, other than they are chinese in origin.  
 
I have a set of Grado RS1i headphones as my go to references.  They are themselves quite forward in the upper mids, but I never found this to be an issue with any of my previous amps.  As a matter of fact, they sing beautifully via the headphone output of my iFi iDSD Micro.  But with this new Icon Amp, that I want to like, the mids go past that tipping point into excessive.  I get ear fatigue rather quickly.  
 
I have ordered a set of new tubes that should be here tomorrow.  They are all of the JJ variety.  My understanding is the JJ tubes might be a bit on the darker side, so hopefully I get back some amp/headphone synergy here.  
 
 
All that said, any further recommendations on tubes to try, before I use this as an excuse to drop a grand on a pair of Audeze headphones?  

 

[MLGrado]

Hi.  I have discovered a few things.  
 
 
Rolling out the stock Chinese EL84 tubes and rolling in JJ Electronic tubes has made a HUGE difference in overall sound.  The Icon amp sings with so much more authority now, and any forwardness in the upper mids seems to be gone.  All this comes at seemingly no expense in treble detail or air.  An amp that I was a bit dissatisfied with, especially after all the great reviews of it and other Icon products, is finally starting to sound like an 'audiophile' product. 
 
 
Ear Fatigue is a real thing.  My ears are now extremely sensitive to frequencies around 2 khz.  Listening to my Grado headphones, regardless of amp, is currently a painful experience.  I expect this condition to reset with some rest.  I have never found my Grados to be overly bright/ painful, until now.  If this doesn't resolve, I will definitely be moving to a different headphone.  Regardless of how it shakes out, I might go in a different direction.  

 

[MLGrado]

Also, I have discovered how ADDICTIVE tube rolling is.  This could be a REAL problem for my wallet!!!!!!!