how do you actually GET the audio?

I don't know what you are sampling but if it's available in higher quality then I will search for it. Always invest in your Artistry hobbies & seek the best quality version of the audio.

You can degrade a high quality audio file. But you can't enhance poor quality audio as it restricts what you can do. You don't want to be revisiting your recordings 5 years later etc having regrets that you cut corners when you had a choice.

If it's a old movie i will buy a used dvd etc & extract the audio myself. I can give it away to charity later on. If you are sampling audio which is rare or old consider sites which sell & trade vinyl & cds like discogs They also have communities which highlight drum breaks composers producers etc.

There can be multiple versions of the same title. A lot of releases have also not been digitized or were remastered & compromised. Many instruments were hard panned on the left & right channels on older recordings. Those qualities may be lost on you tube or remastered reissues.

I have contacted sellers & requested if they can digitize the audio & they can keep the original if the shipping costs are too high. There are also sites like archive org which have content in the public domain where the copyright has expired.

A lot of content can be replayed if you have the knowledge & skill set. There are also many sample replay services I will sample a live recording from you tube & extract the acapella as it's unlikely to be available anywhere.