Incredibly, it’s still magnetic tape running at 15 IPS, on a really good reel-to-reel tape machine.
The highest resolution source you can access is still a high-quality analog source at this point. The highest resolution analog medium is high-speed reel-to-reel tape.
Let’s not forget that most of your favourite recordings were made to tape and the very best recordings of all time were made on tape. Anyone who’s ever heard a good reel to reel tape played on a good machine will know what I’m talking about. There’s a richness, fluidity and power in tape that has to be heard to be believed.
And therein lies the problem – how do you hear this? You need a high-quality reel-to-reel tape machine and some extraordinary and very expensive Tape Project tapes, or similar. There are very few tape releases available and really, this is almost a dead end, unless you can access the tapes.
Next in line, we have good old vinyl. Vinyl is another analog medium, ie it presents a copy of the original file. Good vinyl played on a great turntable and cartridge is close to reel-to-reel, though it can’t match it. The limiting factor is the hardware and pressings in this case. With analog sources and gear, you really just get what you pay for and its a sliding scale. The resolution possible is incredible.
Some of the new high-resolution digital formats are also excellent and hard on the heels of analog, like 24 bit/192kHz, DSD, SACD and other lossless, uncompressed formats. Lossless is a misused term, because all digital methodologies involve some loss, by virtue of how they sample the original. The inherent resolution is very high though, and one could make the argument that the losses in resolution through sampling are made up for by the increased linearity in handling the data that isn’t lost.
Next, we have Redbook CD. CD still has a lot to offer and I’m amazed by how much one can get from 16 bit / 44.1kHz files. I have some superb-sounding CDs and played back on a good CD player, they can sound fantastic.
Probably last in terms of being real hi-fi would be compact cassette tapes and analog FM radio. Both offer good to excellent performance but are very hardware dependent.