I do already have hundreds of Redbook CDs collected through the 80s, 90s and on. I can point blank state that the majority of other disc formats are audibly superior. A lot of it comes down to simple laws of physics. You can’t squeeze water from a rock, because it just isn’t there. Regardless of how great a CD player may be, the Redbook CD format is extremely limited in its dynamic range, materials, amount of data that can be recorded directly impacting resolution, and the frequency range which is recorded onto standard Redbook. Yet physics aside, these Redbook shortcomings are easily validated via side by side comparisons of the same album on two different formats, from the same master, with the same disc player.
"Bright" primarily depends on studio mastering/remastering or a person’s sound system, though can be exacerbated by a format. If anything, relatively speaking, the average Redbook has very harsh edged sounds in comparison to most of the other formats, and Redbook is ’thin’ sounding on average compared to the others. This can be addressed to the listeners comfort by getting quality speakers with a silk dome tweeter such as Dynaudio, or trickery of electronics inside a player, as was done by Bob Carver’s dedicated players of the 1980s and 1990s. In both of those fixes, you’re not hearing the exact material on the disc. You’re hearing the more pleasing version of it created by the equipment to not offend your ears. If that’s what an individual wants for their $, that is what matters. But taking that preference and saying it = standard Redbook superiority is factually false.
Not sure where you’re coming from on this. Perhaps Jays Audio is a great dedicated player. I had a Sony ES dedicated player, and my Oppo 205 Universal blows it away on Redbook. Perhaps Jays Audio is better than the Oppo. Then again, how many people have $5k to blow on a single dedicated CD player and then the equipment needed to appreciate that players abilities, outside of the world of the 1/10% live-in-a-bubble privileged? It's all relative. Play them all on one player, or equivalent players from the same manufacturer, and the superior format will stand out relative to the others. Ie, I have Elton John Goodbye Yellow Brick Road on Redbook, SHM-CD, SACD & BluRay Audio. There is zero...I do mean ZERO comparison in SQ between the Redbook and the other formats. The SHM provides better extension of notes, more resolute bass tones that hit harder and more definitively, more natural vocals, and more defined yet still fuller high notes. The Blu Ray provides greater ultimate extension of notes and decay of them than the prior two, with greater detail and separation of notes from a black background, and improved depth & realism throughout the audio spectrum. The SACD is superior to all the aforementioned, with all of the best rolled into one, plus layers of sound even the BluRay Audio doesn’t present. That’s all from the same master recording. Going from Redbook to any of the other formats on that album is night and day, leaving me ready to throw the CD in the trash, but I keep it to play in the car and not worry if it gets beat up in the travel. Very similar observations on Billy Joel and quite a few other albums including Steely Dan, across many genres.