Could some one explain how to buy best cables?

I would buy Kimber Kable Hero interconnects and Kimber Kable 8VS speaker cables and forget about it. They are inexpensive, sound good, and your done. That's what I did. Then, upgrades can be elsewhere...or enjoy the music.
John Dean

Everyone’s system is different so what works for one will not work for another. Even if the systems are similar the rooms most certainly are not. Throw in personal likes and dislikes and it can get quite confusing and costly. Everyone is well intentioned with their advice but if you follow someone else's advice about what will work in your system you'll probably spend way more than you intended too.

My advice is to establish a baseline for the way your system sounds with good set of well respected but inexpensive cables like what Whoaru99 suggested with Blue Jeans Cable. They'll get you a complete set up for probably less than $100. After you lived with that for awhile and have a chance to learn what you like or dislike about them, get in touch with The Cable Company at www.fatwyre.com or www.usedcable.com, they have a loaner program. Tell them what equipment you have and how much you have to spend and they'll send you several different brands to try out in your system for a small percentage of the actual cost. Keep the ones you like or send them back and try some others. They have a huge database of what other people with similar systems preferred so they take a lot of guesswork out of the whole process.

You may find the extra cost for the boutique cables is worth it or you may not. You will know for certain what works for you with little financial risk and you’ll get an education in the process.

Hope this helps.

When I had a deviant room (suckout, echos, bass bloat, endless reflections) I tried cables to correct the deficiencies I had both in the room and in the equipment. I suspect that is the case for most of us in most situations. Presuming that's your situation too, you can be the luckiest man in the world, throw a dart at a pile of interconnects on a counter and presto, you've got it.

Otherwise, it's trial and error, or figure out as you've been suggested what you are trying to correct, enhance or reduce in your system.

This eliminates the nonsense of what $2K to $50K cables do, don't do and pretend to do.

Best wishes.

Lake you are right , you just educate me, what
other factor affect cables.

Anyone else notice that every cable discussion reads like another version of "Groundhog Day"? It's the same go-nowhere discussion over and over. Author professes naivete and confusion about cabling with the ubiquitous reference to snake oil, followed by the broken-record flaming of hypothetical cable-mongers (otherwise known as "they") who have been duped by the smoke-and-mirror tactics of people like George Cardas and Ray Kimber, only to come full circle to the inevitable confession by the author that he/she already had the answer in pocket.

Cabling is one aspect of this hobby that can potentially bust through all of your forgone conclusions. Room treatment is certainly another. However, it would appear that inside the circuitous boundaries of this banter, most would rather be right than curious.