Buy 12ax7 tube

+1 to Loweider57, he is spot on with all advise . At your price point Tungsram and EI are your best bet . Telefunken is the best overall . Once you go Telefunken, you’ll never go back . I have a pre that takes 2 12AU7’s . I have about $ 2500. invested in 12AU7’s alone  . From RCA to G73-R Telefunkens. The smooth plate regular grade Telefunkens are the best bang for the buck . When looking,  Tungsrams might be relabeled as RCA or Raytheon. If you want Telefunken sound but a little brighter , try the Nickel plates . Happy Hunting , Mike. 

@lowrider57 can you suggest me a good power strip? I see they say connect your amp directly to the wall socket ac,how can it possible when i should use a power strip?
Sorry for my noob questions

And another question
If i can change my speakers with a good audio physic or dynaudio speaker or buy good power strip+power cable+new tubes+usb cable

Which one is better choose?
I just can select 1 option!

Wiremold is a well-built power strip that is transparent, meaning it doesn’t colour the sound and no filters are used. This is not a power conditioner, but is much higher quality than using a multi-plug for your components.
I use a Wiremold with surge protection, meaning it has a circuit breaker to protect against voltage spikes.
https://www.mscdirect.com/industrialtools/wiremold-power-strip.html
Use a strip with the shortest 3-prong cable.

Typically an amp is plugged into the wall receptacle and source components are plugged into a power conditioner to help filter noise from the power line. As mentioned, Brick Wall offers surge protection and power conditioning; the result is a noticeably lower noise floor. Furman is another good power strip/ conditioner. Brick Walls are available used on Ebay.

As far as a speaker upgrade, IMO Audio Psychic is a very special speaker. Is there something you dont like about your current speakers? How do they match up with the Vincent?

I want to say i increased distance of my speaker from wall and bass is better now

Thanks for your power strip advices @lowrider57 
I should buy it