View Single Post
Unread 04-09-2012, 03:25 PM   #2 (permalink)
babatube
Senior Member
 
babatube's Avatar
 
Join Date: Oct 2010
Location: one ARP away
Posts: 2,541
Thanks: 48
Thanked 48 Times in 11 Posts
Re: Phase inverter going?

Quote:
Originally Posted by sixstring531 View Post
Not home to test - but here's the scenario: (Bad Cat Black Cat 30 - hot running tonemonster)

Newer JJ Power Tubes as of late January 2012 - play about 3 hrs a week - power tubes always last the whole year (I change them every year)

Went to practice Thursday and felt like I had to turn it up a notch or two louder to get the oompfh I was used. I also felt like I lost some mojo - can't really describe it in tone other than "slightly thinner and not as big". No noticable (visibly or audibly) problems. I changed the main preamps (not the PI) no change. I put the year old power tubes in and thought it sounded slightly better, but I was still certain I was missing something.

I went ahead and played it Sunday - sounded fine, but again, thought it lacked a tad.

I haven't changed the PI for two years now. It's the 12ax7LPS James told me to put in it and I have an email into him to see what he thinks.

I just didn't know if a dying PI died or gradually got weaker....

the LPS are more fragile and tend to be microphonic because of the larger plates.
i would swap the tube and see how it goes.
__________________
babatube is online now   Reply With Quote