HiFi Rose RS520 streaming integrated amplifier Page 2

When you swipe on the HiFi Rose's inertial-scrolling display, the graphics roll by as smoothly as on any late-model tablet. No surprise: HiFi Rose is a division of Citech, a Seoul-based company that's a leader in ticket-issuing machines and information kiosks.

Traces of the RS520's Koreanness surfaced occasionally. Tap on the RosePodcast icon and then on Genres, and you get a screenful of Hangul characters (the Korean alphabet). RoseFM attempts to pull in Korean stations as the factory default, although changing that to the US or another country is trivial. One of the icons on the display is for launching Bugs, an unfortunately named pay-to-play Asian streaming service headquartered in South Korea. Tapping the icon results in a message that says "It is not a service area."

Ah, language quirks. At times, the HiFi Rose RS520 reminded me of the Russian translator in the movie Tetris, who tries out her best English on an American businessman in Moscow. "Do you require succor?" she chirps, offering her assistance. "Esteemed to meet you!" We know what she means even if the choice of words isn't impeccable.

Because HiFi Rose is an engineering-centric company (footnote 8), niceties like translation and spelling sometimes seem to get short shrift. On the RS520, linguistic quirks were never particularly enigmatic, but perfection is a ways off. When connecting to Bluetooth, the message you get is the slightly off-kilter "Execute [Bluetooth] to search for available devices." The screen that lets you choose among three font sizes for streaming music says, by way of instruction, "Enlarge a Playback information." Even the company's official English-language website (footnote 9) states, "Before the sudden change, the tool until yesterday is meaningless." Jon Derda says HiFi Rose has been "making small changes with each iteration of [the RS520's] firmware (footnote 10), to Americanize the product further." Importantly, the 64-page product manual is written in rock-solid English, no complaints.

I'm all ears
Surprisingly, break-in wasn't necessary. Although I'd received a factory-fresh RS520, its sound didn't change over the three-plus months I spent with the unit. For convenience, I kept it powered on almost the whole time (though I turned off the screen a lot, including at bedtime). But when I did shut everything down for a spell, then returned to listening, I detected no difference between the RS520 cold and after it had warmed up. This may be one of the advantages of well-built class-D amplification, as class-A and class-AB amps tend to sound better at full operating temperature. The HiFi Rose RS520 vaults to that point straight away.

Extended kneeling in front of a component isn't my idea of a good time, so after 15 minutes of setup and half an hour of playing around with the front-panel menus and controls, I interacted with the unit via the excellent, drama-free Rose HiFi smartphone app. The dedicated remote control wasn't for me, as its volume up and down buttons dramatically overshot the intended stopping point: If I wanted to turn down the volume from 70 to 50, and I took my thumb off the button the moment it reached that number, the volume continued downward, stopping at 35 or even 30. It worked the same in the opposite direction but with scarier results: Unintentionally raising the volume to 95 or higher—practically full-blast—is friendly to neither speakers nor ears (footnote 11). Thankfully, the app had no such issues, and of course, Roon doesn't either.

I was impressed when I hooked the RS520 up to my Tekton Moabs ($4500/pair), then my Focal Scala Utopia EVOs ($53,000/pair), and finally the Raidho TD3.8s ($119,000/pair) I have in for review. With each combination, there was weight, control, authority, clarity, and palpability. I heard sweet detail up top that didn't become brittle even on borderline sibilant recordings, such as Emmylou Harris's "Deeper Well" (24/44.1 FLAC, Nonesuch/ Tidal). In the delicate pas de deux between each set of speakers and the streaming amp, the HiFi Rose got out of the way and let the speakers take the principal role, allowing each to express its own personality.

Chet Baker's Live in Paris 1960-1963 (24/96 WAV) isn't an audiophile-grade recording. Ray Mosca's drums have a lamentable cardboard-box quality, and he sounds as if he's using knitting needles instead of wooden sticks. The trumpet is another story. Baker's beautiful, burnished sound comes through gloriously, each note suffused with ache and melancholy even on the tracks that would seem upbeat if you were reading the sheet music. To listen to him play this material is to go on a trip of love and loss. The HiFi Rose did a first-rate job of rendering it down to the tiniest timbral details.

Next, on Two Feet's "Love Is a Bitch" (16/44.1 FLAC, Casual Majestic/Qobuz) and Me'shell Ndegéocello's Peace Beyond Passion (16/44.1 FLAC, Maverick/Qobuz), I learned that the RS520 is undaunted by a good bottom-octave challenge, producing taut, grippy bass.

The RS520 strikes a smart balance between liquidity and detail. Its sonics tip ever so slightly forward, but that's what makes it revealing. Speakers that tilt heavily analytical might be best avoided as partners—unless you pull down the top end a touch with a parametric equalizer like the one built into Roon. (You'll also find an equalizer in the 520, with five frequency bands, adjustable Q, eight factory presets, and three memory banks to save your settings.)

On almost every track, the soundstage was wide and convincing, not only left to right but also front to back. On David Bowie's "Bring Me the Disco King," a track from Reality (16/44.1 MQA, ISO/Tidal), I could hear the snare drum precisely placed 5–6' to the Thin White Duke's back left and well behind him. The ping-pong panning effects and assorted soundstage frippery on Bear Project's "Punch," from the gorgeously trippy ambient album OHM (16/44.1 FLAC, NL/Qobuz), were a delight to follow, appearing as they did all over the room. Cerebral electronica doesn't get much better than this.

This is the end
I loved my time with the RS520; this Rose is blessedly free of thorns. It's a serious piece of cutting-edge technology, uniquely outfitted with a user interface that's infused with playfulness. The Rose is free of glare, grain, and tizziness, unlike most class-D amplifiers of 10–12 years ago. Audiophiles of a certain vintage tend to swear by class-A or class-AB amps, but their knees may be jerking. D may have once stood for "Don't"; now, perhaps we can settle on "Delectable."

Returning to automotive terms, the HiFi Rose is a fast, impressively appointed sports car for the price of a Volkswagen Golf. Fahrvergnügen indeed!

Footnote 8: The numbers can fluctuate, but US distributor Jon Derda told me that the last employee headcount he's aware of was 27, "with only two people handling sales and marketing, the rest being engineers."

Footnote 9: See eng.hifirose.com.

Footnote 10: Updates are frequent, and they are downloaded and installed automatically via the network.

Footnote 11: Inexplicably, two years earlier, I'd had almost the same problem with the NAD Masters M33 and its volume control. Maybe I have a poltergeist who dislikes powerful streamer/amps ... or who is very hard of hearing.

HiFi Rose
932 Yangjae-daero, Songpa-gu
South Korea
(312) 841-4087

MZKM's picture

If the distortion/noise/jitter were better (not saying it’s for sure audible), this would be an excellent product. I’d say 8/10 as-is.

I’ve seen a few of these at the Florida Audio Expo, this model powering the MoFi SourcePoint 10s, really nice to have a nice display and HDMI out.

tenorman's picture

Very enjoyable, informative and well written review . Cheers

RvB's picture

Thanks for the kind words!

JRT's picture

The low resolution of the images included in this article make it overly difficult to read the rear panel markings. I subscribe to the magazine, and well understand that higher resolution images are available there, and I have also read the author's description in the text, but the following image excerpted from the marketing webpage for this product at the HiFi Rose website might be useful for easy reference to some others in your readership.

Also... I did not see mention of this in the article, but the marketing webpage for this product at the HiFi Rose website mentions that an external CDROM may be attached for direct real time playback, or to allow digital audio extraction (CD ripping) facilitated by HiFi Rose's proprietary variant of Google's Andriod operating system utilized in this streamer-DAC-integrated-amplifier.

Some other info which may be interesting to some:

After reading the article, and after reading the information on the marketing webpage for this product at the HiFi Rose website, and after downloading and reading the manual, it is still not clear as to whether or not the preamplifier outputs can be utilized to feed a signal to subwoofers while also using the power amplifiers' outputs to power a pair of loudspeakers, with all sharing the same volume control. Else the only way to send shared volume controlled signal to the subwoofers would be with high level signal from the power amplifier outputs powering the loudspeakers.

JRT's picture

The author mentioned, "...I'll note that the $5999 NAD M33, which I reviewed for a different publication, comes close; it's specified to produce 200W of Purifi Eigentakt power per channel with an 8 ohm load."

My understanding is that the various NAD products utilizing Purifi's Eigentakt modules (or authorized copies thereof manufactured under licensing agreement) have been utilizing the Purifi 1ET400A Eigentakt module which is limited to 25A peak current output. A more recent Purifi 1ET7040SA Eigentakt module can deliver higher 40A peak current with similarly very clean performance.

Buckeye Amplifiers is offering their "Purifi 1ET7040SA Amplifier, Monoblock v2" for $950 each (so $1900 for stereo pair), in direct sales. It is a no-frills design, especially in the external aesthetics, but does include balanced inputs (XLR ports) and switch selectable input gain.

As compared to the amplifier which is the subject of this review, the Purifi Eigentakt modules are very much more load invariant, and so can exhibit much flatter frequency response, reduced linear distortion.

A couple of other very good alternatives from Buckeye would be the Buckeye "Hypex NCx500 Amplifier, Monoblock" for $750 each, and the Buckeye "Hypex NCx500 Amplifier, 2-channel" amplifier for $1095.

Chick Korean's picture

The manufacturer initially rated this unit at 250WPC on their site. The US distributor's advertorial shortly thereafter for the same product rated it at 200wpc, so I emailed the distributor to inquire about the discrepancy and they informed me that '200W was more accurate'. The manufacturer subsequently changed the output rating on their website to 200 wpc.
At any rate, I eventually purchased one last year and I strongly objected to the user interface of the device itself and it's app. I returned it to the dealer and ordered a NAD M33 instead, with which I am very satisfied indeed. The built in BluOS is a dream and the app is still among the very best in the industry. BTW, the above mentioned M33 as reviewed in this publication by Kalman Rubinson in 2020 measured 255Wpc into 8 ohms and 460Wpc into 4 ohms. Another publication's bench test resulted in similar numbers. Yes, it is 40% more money than the Rose, but well worth the investment. And...it's a (Chinese manufactured) Canadian (engineered) product to boot.


I should add that I thought the Hifi Rose sounded pretty good to me at first blush, although I did not keep it long enough to either break it in nor to familiarize myself with it's sound qualities over time. BTW, published spec at the Hifi Rose US website remains "200 watts x 2 into 8 ohms", and not 250.

Ortofan's picture

... comparison with the combination of a Cambridge CXN v2 Network Player and an NAD C 298 power amp (which uses Purifi modules)?



georgehifi's picture

"though its class-D output stage has a higher level of ultrasonic noise than I usually find with such designs.—John Atkinson"

You found the same with the RA180 of Rose's, also a GAN output device Class-D amp of theirs.
Yet the Technics SE-R1 also GAN device seems to have none of this from what I've seen, wonder if it has something to do with the 3 x higher switching frequency (1.5mhz) and output filtering they use on it to keep the left over switching noise rubbish and phase shift away from the 20hz to 50khz range?

Cheers George

mr_bill's picture

I see it streams Apple Music - which I have seen no other streamer do.
This is truly Apple Music and not just Airplay2?
If it really is Apple Music does it stream the high res Apple Music files too?
Does anyone know the answer?

JRT's picture

FiiO R7 ($700) streamer, DAC, preamplifier, headphone amplifier, etc. can stream high resolution lossless Apple Music or can stream from other sources to analog or digital outputs without forcing any sample rate conversion. Most Android-based implementations will force sample rate conversion to 48kHz, but this one does not.

comp.audiophile's picture

To clear up some question about the Apple Music implementation.


In-app Apple Music does not support lossless streaming. Currently, the audio source of Apple Music Official SDK (Apple Music Kit) only supports AAC.