Buy 12ax7 tube

Thanks everyone for your advices
I have another question,can bad electricity reduce dynamic of sound and cause bloated bass?

Bloated bass could be caused by speakers positioned too close the the wall or by the amp not having enough power to drive the speakers. But, your amp shouldn’t have this problem.
It could also be caused by the choice of tubes. And lack of dynamics is often due to tubes.

Your power setup could be causing lack of dynamics and muddy bass, but I wouldn’t call it bass bloat. It would be a lack of clarity or transparency. Your components should not be plugged into a cheap multi-plug, especially the amp. Amps need unrestricted clean AC feeding them from the wall receptacle.

As stated before, I recommend that you use a power strip with a short cable (under 6 ft). Also, replacing the stock cable on the amp would provide better sonics; better dynamics, transparency. I think you should start by improving your power to all your components especially the amp.

Another vote for Psvane 12AX7-T11. Rolled them into my Vincent SA-T8 Pre. Massive jump in performance. Very bright initially, but settle nicely after 70 hours or so. Quiet, superb dimensionality, highly resolving.
And yes improving the Power going to your Equipment will help greatly.

Go to Brent Jesse Tubes and read... Tubes are heavily researched for character and tested. He stands behind his inventory.

I use Telefunken smooth plate on my McIntosh C2300 MC phono stage and Gold Lion gold plated pins, cryogenic treated for my line stage.