It's a pity the Astell and Kern AK380 portable music player costs $4799. It should be free, just like an education and visits to the National Gallery are free. It provides a joy in which everyone should share, and it would alert the unalerted to just what pleasures recorded music can provide. It presents about as close to perfectly reproduced music as most people could hear. It's a joy, an epiphany, a stream of shivers up a spine.

But people make such things to sell for a profit so an AK380 costs $4799 and your first reaction is not so much "Awesome sound!" as "Whoa! Five large for an iPod?". And it's not even an iPod.

Some context. At the turn of the century the portable music player market was dominated by one brand basking in the sunshine of the mp3 revolution: South Korea's iriver. As storage grew cheaper the company stayed at the top with constant updates and tricky tech. But everything changed late in 2001 when Apple launched its original five-gigabyte iPod with "1000 songs in your pocket" (as long as the songs averaged three minutes). With iTunes behind it, the iPod sold 600,000 units in 2002 and reached a million six months into 2003. Six months after that, two million. iriver? iwho?

But with enough loyal customers behind them the South Koreans beavered away improving the technology, and in 2013 launched the Astell and Kern brand aimed squarely at relentlessly fussy, pedantic, purist audiophiles. The reviewers didn't get the first model, the AK100. It was criticised for not having speakers or a high-res screen. It didn't even have a camera. It cost $700 in the US, by far the most expensive portable on the market, and all it did was play music. The audiophiles, however, celebrated a portable that finally played music at CD quality.

Now there's the AK380 at $4799 and all it does is play music. But oh, how it does that. Forget 16-bit/41.1-megaHertz CD quality – this goes up to 32/384. It handles just about every electronic music storage format, including single and double-rate DSD files, WAV, FLAC and AIFF, as well as humble MP3, WMA and AAC. It has two digital-to-analogue converters (DACs), one for the left channel, one for right. It's Wi-Fi compatible to stream and download music wirelessly. It has Bluetooth aptX. It can be used as an external USB-connected DAC to replace your computer's sound card. You have your choice of balanced or unbalanced outputs. There's 256 gigabytes of on-board memory, plus a micro-SD slot handling cards of up to 128GB. There's an optional charging station, a clip-on amplifier and a CD ripper. To summarise: the AK380 is the duck's guts.

At 230g it's heavy and the screen controls can get fussy but the volume wheel is a ripper. The 10-hour battery life is too short. I had to read the online owner's manual to explore it fully, and there's only a USB cable for charging. But team the AK380 with good headphones (I used Oppos) and there's a remarkably wide soundstage that locates every instrument. You hear the cello strings shimmer, cymbals decay lusciously. Definition is fine enough to differentiate every instrument, but a jazz sax remains syrupy. Even with budget headphones (I used Grado SR60s) the music is airy and spacious with a fragile delicacy that hangs, lingering.

If $4799 for a portable doesn't scare you, have a listen: this is a serious proposition. If it does, pretend it doesn't and have a listen anyway. It will rock your world.