Talking about “true sound” I was thinking of the good old records:
No compression, 1:1 cut.
Played with a high end turn table ( including high end sound pickup) amplifier and speakers,
I would call this “true sound”.
Are there others who got records and playing those?
I don’t have vinyl. I have a large collection of CDs though, and some old cassettes (CDs are a vast improvement!)
I have a few vinyls, I wish I had more butnits hard to get around here. Either the stores mark them up an insane amount, or they are wiked cheap which is exactly how I got mine. Nothing beats 35 cents each at the goodwill
I saved several boxes of vinyl records (over 200) from my military days…who knew decades later they would make such a come back. Finding a turntable was a different story. Mine was belt-driven (back in the day). Finding a new belt took much longer than expected.
I know what you are speaking of.
The belt driven turntables.
The belt gets loose and the rubber brittle.
Replacement is hard to be found.
I have an old Thorens (Switzerland) and the company is still producing such turntables.
Whenever you come over one like this: take it! 
Today I tested my equipment! (45 years old)
What a sound, deep full basses, crisp trebles.
Not to compare with those speakers we are talking about.
I have a few vinyls but nothing crazy
Only have a small collection of Vinyl, mainly jazz albums but do have access to 6 box loads that are in my parents attic (which are probably scratched like crazy) 
Those scratches, I know.
So disturbing.
Sometime so deep the needle jumps.
If records are dirty it is possible to wash.
I hade done this removing fat greasy fingerprints.
But a scratch… Oh ja!
Are there ways to repair scratches?
I suppose this strange repair doesnt remove any of the phyisical scratches.
I would NOT DARE to do that with that " wood glue".
This kind of “smearing” is quite dangerous doing this ON the turntable!
Normally only the dust needs to be removed by using special brushes.
If a record needs intensive cleaning there are many cleaning kits.
And there are special washing machines for records,if someone has a huge collection.
But removing a physical scratch is not possible.
Actually @Chiquinho, I have used the wood glue method to help repair scratches and also help unwrap a record before. The best way with scratches is also using a toothpick and gently rubbing the scratches area
Tooth-pick method : Sounds better!
May help to reduce the scratch a little so the pickup will not jump.
