I had not even considered SSD, interesting that you say they have better sound quality.
I see Samsung makes a 4TB internal SSD that sells on Amazon for $450. And external SSD 4TB's start at $719.
But presumably you do not need to buy a backup. And you do not have to deal with a failed HDD, which (for a simpleton such as me) also involves paying a computer tek for help.
https://www.amazon.com/dp/B07L3CLM2B/?coliid=I5HJ3Y20YG83D&colid=2GO5XW7KH31YJ&psc=1&ref...
https://www.amazon.com/dp/B078TMW9PX/?coliid=I3AL1TYDZUEM5E&colid=2GO5XW7KH31YJ&psc=1&re...
Btw, i also download movies and Attenborough nature programs, they take more space than just music. Movies I seldom keep, usually dump them after a few minutes trial. Atttenborough I save for my grandchildren (and myself).
Also, the 8TB I bought at Costco for $120 sells on Amazon for $140.
https://www.amazon.com/Seagate-Desktop-External-Hard-Drive/dp/B07CQJBSQL/ref=sr_1_6?keywords=externa...
If you have a minute, please describe your sound system -preamps, amps, speakers???