That sound is right for me.

@baylinor  it's meaningless to say my English good or bad here. If you are not clear for whatever reason, you can just ask me.

Does that work for you? Let's go into the topic.

You may be able to contact the author of the video and ask questions. They may be able to give you clues of how to find what you’re looking for. 
 

Best wishes-

@uncledemp  you are definitely go into the core. He replaced the original crossover of the speakers and redesign a new tube crossover for the speakers and he said his crossover is much better. So now I have some clue, it is not just preamplifier and amplifier. 

@runwell That’s good news, one step closer! Best of luck finding what you’re looking for. Have fun! 

Much to my amazement, some YouTube sounds better than badly engineered hi-rez.

Case in point, remastered hi-rez of Led Zep cannot even remotely compete with YouTube’s Playing for Change cover of When the Levee Breaks.  You can actually hear the bass line!  
 

Check it out.  It’s wonderful.