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Collecting CDs

Why?

As I write this it's 2023 and if you're just looking to play a popular song, Apple Music and Spotify do great work. However, I've found a number of recordings/masterings over the years that I listen to often but aren't part of any streaming service.

Notes On CDs

Quality

After around age 12 your ear can only hear sounds up to ~14kHz at normal listening levels (dbs) and that only declines with age. CDs are sampled at 44100Hz and can represent frequencies up to 22.05kHz. This means that a CD can represent more sound than you can hear. While a record can accomplish even more as it's analog, you can't hear it no matter how much your friend with a $50K record player tries to convince you.

SACDs

Well, if upper limit quality doesn't matter, why do I collect SACDs? It's a resonable question but mostly for the same reason I collected CDs. SACDs normally have more than a single layer and often three. The first is the standard Redbook, named after the redbook specification but more commonly called compact disc or CD. These hybrid SACDs will play in any player. Wait, so you're spending $30+ on a normal CD? Not exactly, often times the SACD is a remastering or remixing of the original work from the original tape drives. The sound engineering might have removed reverb from drums to tighten the snare or perhaps even repaired the original tap drops, when the music caused the electrical to cut out such as Black Sabbath's original Writ recording. Fixes, tweaks, and enhancements are all part of the remastering process. Other layers on an SACD might be a surround sound mixing where the original tapes (one per mic) were used to recreate a studio or theatre experience for those with the required speaker setups. Finally, the most used is the 2-channel high definition layer which serves very little purpose over the CD layer if one exists unless they use different masterings for each. In fact, many times the CD layer will be the original layer and the SACD 2-channel will be the newer mastering. Sometimes the 5.1 (surround) layer is the only different mastering on the disc. Needless to say, it pays to research an SACD before making the purchase.

Sound Ranges

Finally, you'll recall the frequency ranges which can be represented by the CD format, well ignoring your old pathetic ears for a second, the amp, dac, and speakers you're using to recreate the music from the CD all need tobe able to reproduce the appropriate range of music. Many speakers only go to 20kHz so what's the point of media that produces more than that?

Loudness

Music is produced to make money from the time it leaves the musicians lips and often before. Mixing is about making people's ears love what they're hearing *where they hear it*. Originally, CD players were pretty expensive and large so they sat in homes where the only people who could afford a player listened to music. Home players (components) could reproduce the sound but they also didn't compete over ouside noise. They could be quiet recordings meaning that they represented the full range of the music from the studio. This didn't last. Soon we were listening to CDs in the car and while walking about, though the format's tendency to skip wasn't great for exericising. Afterall, a CD is basically just a small record that's loaded into memory and played. Old players skipped a lot because memory was expensive and you simply couldn't afford to cache that far ahead. Oh yeah, when you listen to a CD, you're actually listening to a sound file loaded into memory and converted to audio by a digital to analog converter which operates at it's own frequencies and is often a source of noise (distorition) itself. I digress. So now that people are buying music for their cars in the 90's, the sound engineers need to produce CDs that will play OK at home and OK on the road. This is a really tall order because the car is loud, especially in those days so the music on the actual CD needs to be louder. The good news is, human ears love loud. So they increased the loudness on the CD, killing the high-highs and low-lows but by zooming in on the middle, things gotmuddier for the home listener but sounded great to the car audio set. You might remember how much they loved bass!

Hardware

If you peel back the onion just a little bit on sound recordings you'll realize that what you're listening to is the interpretation of a sound engineer who is older than 12 and can only hear perhaps 15kHz deciding how much sound to record first to a tape sent to a digital signal, written to a file, manipulated to work in the most common listenting environment (least common denomenator for the largest target market), shipped to different plants all running different hardware, using different materials-some are Super Hard-, popped into a player that has a noisey signal path such as poor wiring, a fancy tube, a rubbish DAC, a "high-fi" amp, and speakers. In short, it's similar but not exactly like the original by the time it hits your old ears. In short, don't fetishize hardware, you'll never reach an end, focus on the music and you'll be happy.