Panasonic DP-UB420-K review

What the maker puts in writing

• “This 4K UHD Blu Ray player… offers high-dynamic range playback in three 4K/HDR formats HDR10+, HDR10 and hybrid log-gamma (hog)”
• “4K high-precision Chroma Processor for 4K image color signals (4:2:0) that are interpolated into 4K (4:4:4) by a multi-tap Chroma process”
• “Twin HDMI Pure AV (Twin Isolated Output): High-Quality Sound from this 4K DVD player”
• “Hi-res sound… for Hi-Res studio Master sound from DSD (5.6 MHz/2.8 MHz/11.2MHz), ALAC music files and WAV/FLAC/MP3/AAC/WMA/AIFF formats”
• “Works with Alexa to command a variety of operations without your remote, Plus Access a wider variety of 4K content with 4K VOD streaming from Netflix, YouTube and Prime Video; also works with Google Assistant”
• “HCX Processor (Hollywood Cinema experience) to deliver powerful, precise Chroma and HDR processing”

Three HDR formats, named — and the one that is missing

HDR10 is the baseline every Ultra HD Blu-ray carries: one set of brightness instructions for the whole film. HDR10+ adds scene-by-scene metadata, so each shot is mapped to what your television can actually show. HLG is the broadcast format, used for live 4K television.

The absent one is Dolby Vision, which does HDR10+‘s job by a different and incompatible method — and which the UB820 at $629.99 adds for $262 more.

Whether that is worth it depends entirely on your television. A set that supports Dolby Vision but not HDR10+ would gain; a set that supports HDR10+ would not.

And note what the competition publishes. The Sony UBP-X700U at $328 says only “HDR (High Dynamic Range)” and names no format, so you cannot tell what it will do with your set.

There is also a curiosity on the dearer Panasonic worth knowing before you compare them: the UB820’s bullet 5 lists the same three formats as this one and omits Dolby Vision — the single feature that justifies its price — while its title and description include it. That bullet appears to have been copied from this listing.

The chroma claim, in plain terms

4K image color signals (4:2:0) interpolated into 4K (4:4:4) by a multi-tap Chroma process.

Those numbers describe how much color information is stored next to the brightness information. A 4:4:4 signal carries full color detail for every pixel. 4:2:0 carries a quarter of it — color is averaged across blocks of pixels, which is nearly invisible on most material and saves an enormous amount of space.

Every Ultra HD Blu-ray is mastered at 4:2:0. So the player is reconstructing the missing color detail by interpolation.

Where that shows is on fine colored edges — red text on black, a bright flag, subtitles — which can shimmer or smear when color resolution is low. It is a real improvement on real material, and it is not the same as having the information.

Twin isolated outputs, and the better reason for them

Panasonic leads on sound purity: isolating the audio output from video’s high-frequency switching. Arguable.

The compatibility case is not arguable. Two sockets let video go straight to the television and audio to an older amplifier that cannot pass 4K HDR through itself.

That is a frequent, concrete problem: an amplifier from before 4K becomes a bottleneck, and you lose either the picture or the surround sound. Twin outputs end it.

Three players here have them, and none mentions this.

DSD at three rates, which makes it a music player

DSD (5.6 MHz / 2.8 MHz / 11.2 MHz), ALAC… WAV/FLAC/MP3/AAC/WMA/AIFF.

DSD is the Super Audio CD format — audio as a very fast stream of single bits rather than slower multi-bit samples. Those three figures are DSD64, DSD128 and DSD256: the original SACD rate and two multiples. Supporting all three means a hi-res download plays natively instead of being converted.

With FLAC and ALAC — both lossless — alongside, this is a credible digital music source as well as a disc player.

Only one other listing on this shelf names any file format: the Panasonic DMP-BD84P at $117.99, which also includes DSD.

What is not published

No HDMI cable. On a 4K HDR player that is not a trivial omission: 4K at 60 Hz with HDR needs real cable bandwidth, and an old cable from a drawer frequently drops out or sparkles. The Sony UBP-X700U at $328 includes one; all three Panasonics here do not.

No HDMI version, which on a 4K player is the specification that decides whether 4K/60 with HDR passes at all.

No region code. Nine players here publish one and all nine say A/1; this says nothing.

1,400 g is published. The catalog’s 270 × 95 × 378 mm is worth checking against your shelf rather than trusting — on this shelf only the DMP-BD84P publishes dimensions in its own bullet that match the catalog.