Reproduced from an audio engineer at Dolby laboratories:
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The state of the art digital audio, at 192kHz/24-bit, is the highest fidelity medium available to the average consumer anyway. That allows the disc itself to deliver a 144dB dynamic range and perfectly sample frequencies up to 96kHz. However, you're highly unlikely to find any analog hardware that'll reproduce that as is. But it's entirely possible to create a work that fully uses that range, as long as you're mixing digitally. You can get 192kHz/24-bit audio in 2-channels on DVD-Audio and in up to eight channels on Blu-ray disc.
Consider for a minute what 144dB of dynamic range actually means, though. If you had a stereo that could faithfully reproduce that, you wouldn't be able to hear very quiet passages unless you had the very loud passages capable of being so loud they could actually do damage to your hearing. So, for example, set the level to exactly match the dB,spl scale (sound pressure level, measured in dB). Your threshold of hearing is 0-20dB,spl depending on frequency, but over 130 db,spl or so, your ears are screaming in pain and might be permanently damaged. So this would cover the entire audible range.
LPs are increasing in popularity these days, but kind of in spite of their specs. An LP can in theory reproduce audio up to about 40kHz, but it has to be half or quarter-speed mastered for that, because otherwise, the cutting lathe would be damaged. And most turntables can't get close to reproducing that range, that's one of the things very expensive audiophile turntables give you. An LP can also only deliver about 60dB dynamic range, about 12-bits worth. Some very good pressings on very high quality vinyl might extend that to 65-70dB, but it's not even close to CD.