Cayin A-300b vs Muzishare x9

@cb3489 finally upgraded all tubes on X9 :) i got PSVANE Acme 300b and PSVANE 274B Tii. Using Tektons perfect set 15s.  The sound is really good. It improved amazingly. Huge bass sound level and more noticeable details

Congratulations on your successful outcome. I’ve stated before that yes premium 300b tubes are expensive but worth it for the substantial improvement in subsequent sound quality they provide. A good 300b amplifier deserves the use of the higher tier performance tubes. You may as well get the most you can of an amplifier’s potential.

Charles

Thank you for the update cb3489. Those ACME 300B is not cheap but good to know it improve the X9 much.

I brought a pair of LINLAI 7300B. That pair also tightens the image compared to stock 300b. I didn't listen long enough to see how much those LINLAI tubes can improve over stock ones. Stock 300b is working well after I added the Denafrips Pontus II.

My X9 left channel lost sounds once a while. China HIFI wants me to ship the unit to Michigan for authorize repair shop to check. Instead of shipping, open the unit and solder the socket. The problem disappeared. While the bottom over opened, I checked wiring and noticed some wires and caps were very close to each other. I pushed its part and now very low noise/statics from the unit.

@slowestrider Oohh my God, I bought opus ii last month too :) it indeed made a big difference too. 
i am glad you fixed your amplifier issues. That  is one of the reasons i love tube amps. We can just open it and fix it or upgrade it of course if someone is into it.