HiFi Rose RA180 integrated amplifier

Sometimes it's good to step outside your comfort zone. In fact, I relish new and novel experiences. It's a major reason I enjoy attending hi-fi shows and events: for the chance to see and hear new things—new hi-fi equipment, especially equipment that's groundbreaking or unusual.

Sometimes a component speaks to you visually first. It reminds me of an expression about food presentation that loosely translates to "You eat with your eyes first" (footnote 1). Sometimes, you listen with your eyes first, too.

Love at first sight is too strong, but the first time I laid eyes on the HiFi Rose RA180 integrated amplifier, I was smitten. It was on static display at AXPONA in all its silvery, mechanical glory. "Output level meters and a full suite of controls grace the RA180's solid aluminum chassis' front panel," I wrote in my show report. "In a nod to mechanics, the volume control's moving cogs are visible behind a clear hexagonal covering"; putting the insides on the outside, a modernist touch. "The large volume control dial is topped with a chromed HiFi Rose brand symbol. The knobs, dials, and cockpit-style toggle levers have a nice, sturdy feel. Bonus: When you use the included IR remote control to switch sources or adjust volume, you can see the physical dials move (and they make a little sound)."

1122rose.1

The next day, the RA180 was making music, and I returned to hear it, briefly, driving a pair of Piega Coax 711 floorstanding speakers from Switzerland. "I ... recall highly resolved detail that stayed natural, not overhyped," I wrote. "The deep voices of Nick Cave and Leonard Cohen came to life on a couple of live tracks. Bass was substantial; highs were airy and smooth."

Nagra or Brazil (the movie)?
Intentional or not, it's hard not to notice a resemblance to Nagra styling in the RA180's knobs and dials—but in its stylized, even gratuitous mechanical features, there's a steampunk element, too. It's pure-analog (class-D, although HiFi Rose calls it "class-AD") with four channels to facilitate biamping or bridging (so-called BTL mode, footnote 2). A small switch on the back toggles between the modes. (Speaker cables must also be reconfigured of course.) Two rows of speaker outputs allow two pairs of full-range speakers (two channels or four channels) to be connected. A turn of a front-panel dial lets you switch between A and B.

Biamping is facilitated not only by the RA180's four channels but also by its built-in active crossover, configured to cross over in the midrange or treble, although it only rolls off the higher-frequency channel—not the lower—between 600Hz and 6kHz. There's also a HF gain setting, from 0 to – in 3dB increments. These controls, which could be likened to the amplifier on a subwoofer at the other end of the audible range, are specifically intended for driving a supertweeter.

Unusual features like these are complemented by classic features including tone controls for treble and bass, a balance slider, and a subsonic filter. A "Pure Direct" option, controlled by a big lever on the front panel, allows all preamplifier functions—balance, tone controls, the crossover, even the volume control—to be bypassed, allowing the RA180's use as a pure power amp. (Of course, you can bypass just the crossover using a different switch.)

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The RA180's built-in phono preamplifier is suited for MM or MC output; yet another toggle switch, this one on the back panel, allows you to choose one or the other. Unusually, you can customize the phono equalization curve on the RA180 with a choice of five low/mid turnover frequencies and six HF rolloff rates (RIAA settings are clearly indicated on the dials)—yet the phono load impedance is fixed at 47k ohms for both MM and MC, according to the specifications: no impedance-loading options.

Front-panel switches allow the illumination of the faceplate at three levels—I kept it on, on the middle setting, as it shows the amp's design details to nice effect—and a front-panel attenuator switch lets you turn the volume down to "a minimum level."

The RA180 is equipped with five input pairs: three RCA, one XLR (balanced), and one phono (on RCA of course). For a description of the outputs, read on.

The Korean company has quickly become known for its sleek network streamers with large touchscreens, and soon, the company will release an integrated amplifier with typical RS-series styling. The RA180 is an obvious departure: a mechanical-looking, all-analog (class-D) amplifier. Like the RS250, its streamer sibling, the RA180 packs plenty of functions into its chassis, but that's where the resemblances end.

It takes guts
The RA180 is, as I've already written, a class-D design. Some of the advantages of class-D are well-known, most notably higher efficiency, which allows more power to be packed into a smaller space with less heat. HiFi Rose says that each of the RA180's four amplifier channels "supports" 200W into 4 or 8 ohms. When two channels are bridged, it can output two channels of up to 400Wpc.

1122rose.ins

There's a retro element to the styling of this amplifier, but what's inside is au courant: gallium nitride (GaN) FET transistors in place of the standard silicon ones. A bit of online research (footnote 3) pointed to some advantages of GaN FETs over silicon FETs: GaN FETs respond faster to transients, dynamic swings, etc., with less overshoot and shorter recovery time. The result is faster switching times (with less "dead time") and more precise switching with less ringing, distortion, and EMI (electromagnetic interference). Class-D designs use negative feedback to offset such distortion; silicon-based amps need quite a lot of it to perform at their best. Starting with more precise, faster amplification means that less feedback is needed. GaN technology is also said to allow wider bandwidth: The RA180 integrated's response extends up to 90kHz, according to HiFi Rose's specifications. Sonic outcomes of GaN-based FETs—what Stereophile is all about—are said to include less harshness and more smoothness, improved detail, and a more neutral presentation.

The RA180's balanced power supply uses SiC (silicon carbide) FET technology and deploys a PFC circuit ("power-factor correction circuit," says the HiFi Rose literature; this compensates for impedance elsewhere on the line to align the phase between current and voltage). HiFi Rose says it's "designed not to be affected by sudden load fluctuations."

Hands-on
During my first encounter with the RA180 at AXPONA, HiFi Rose importer MoFi's Jon Derda mentioned that this was an amplifier for which he definitely read the manual. I thought, this must be an unusual amplifier. I was right.

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The back panel is crowded by 16 loudspeaker binding posts in two rows of eight, with a three-position toggle switch below. Some of the labels for the speaker inputs are printed right-side up and upside-down, presumably to make it easy to read when you peer over the top of the amplifier to view the back panel.

Early in my time with the RA180, I'd connected cables from the MBL 120 speakers in the RA180's terminals in a way that seemed logical, but music only played through one speaker channel. It turned out that I hadn't moved the toggle switch to the correct position—from OFF back into BTL mode—after I'd switched the cables' inputs. Once I realized that the "A" and "B" in the manual's instructions referred interchangeably to modes as well as each row of input terminals and the toggle text, it was smooth sailing. Read the manual carefully.

To control the amp, I relied mainly on the front panel. For basic needs such as volume, muting, on/off, etc., the RA180's smallish IR remote sufficed. You could also use HiFi Rose's RoseAMPConnect app for Android or iOS.


Footnote 1: Widely quoted and variously attributed, the earliest and most convincing source I've found for this quote is De Re Coquinaria by first-century Roman gastronome Apicius—though one suspects the aphorism was old even then.—Jim Austin

Footnote 2: When I first saw this, I thought it was a reference to the superstar Korean boy band—but no, that's BTS. BTL stands for "bridge-tied load," a reference to a common method of bridging two amplifier channels to increase output power.—Jim Austin

Footnote 3: For more, see bit.ly/3KjTgJe or this AES paper (free for AES members, expensive for everyone else): aes.org/e-lib/browse.cfm?elib=18612.

COMPANY INFO
HiFi Rose
US distributor: MoFi Distribution
1881 W. Bryn Mawr Ave.
Chicago, IL 60660
(312) 841-4087
ARTICLE CONTENTS

COMMENTS
Jack L's picture

Hi

Indeed. I still recall my gourmet friend who goes for international foods on his offshore business trips, told me:

"Japanese cuisines are for the look (artistic-like display on the plate), Chinese food is for the taste & western cuisines are for the smell."

Yes, many auido fans like to "listen" with their eyes first. But not for me, in any audio shows, if the music does not sound right before I walk in the demo room, I don't even both to walk in at all.

If the music comes out from the demo room sounds OK, then I would walk in & sit down & listen for a few minutes. If it sounds really nice, then I would start to ask questions.

Otherwsie, I would just say thanks & walk out without further questions. That's it!

Likewise, for any audio studios ! Sound always comes first before I bother the look & price.

I design/built/upgraded audio rig at home looks like cheap crap, yet I love spend numberless hours of my leisure time there to enjoy the music masters re-performance there.

Listening with my own ears is believing

Jack L

JRT's picture

Normal human brain function, in dealing with various cognitive dissonance, can place visual perception ahead of hearing perception, where visual perception can change hearing perception.

The McGurk effect provides example of some of this.

https://en.m.wikipedia.org/wiki/McGurk_effect

As for the subject matter of this review, I would not want the gimmickry and whimsical aesthetics of this thing, as it reminds me too much of the old Rube Goldberg cartoons. I would rather have something far less integrated with cleaner functional aesthetics and better performance.

Jack L's picture

Hi

OK. You don't have to throw me the book !

It's common sense for any mature music lovers, like yours truly.
That's why I use my ears only for gauging any audios to minimize "McGurk effect" & the likes.

It also has brought in the huge controversail audio blind tests.

Music is for my ears for my enjoyment gauging on live performance. I don't give a rat's ass to whoever saying whatever else.

Listening with my own ears to the music is believing

Jack L

Jack L's picture

.

JHL's picture

...when needing erudition on (snort)

Quote:

normal human brain function

which I assure you I do all the damn time, is to hunt up the initials JRT in a comment thread.

LOL. The very pretense.

You even summarize like a drone, jeenyus, as if Normal Human Brain Function could appreciate art. Or "better performance". I have zero doubt now but that it'd McGurk both. Is that the term I want? McGurk?

"Self-delusion"? For years I watched gasbags vomit on normal human engagement in music and the technical arts and applied sciences, but now? Not so much.

Long-time listener's picture

Research has also shown that people with "normal brain function" can overcome biases when they are made aware of them. If we choose to consciously reject visual influence and concentrate on what we hear instead, we can do so. It's not a big problem for intelligent people.

Indydan's picture

Hey Jack, crapping with your own butt is believing...

Jack L's picture

.

Indydan's picture

Hey Jack, where you at? Your wife is looking for you...

Jack L's picture

.

Julie Mullins's picture

Yes, many audio fans like to "listen" with their eyes first. But not for me, in any audio shows, if the music does not sound right before I walk in the demo room, I don't even both to walk in at all.

If the music comes out from the demo room sounds OK, then I would walk in & sit down & listen for a few minutes.

In general, I generally don't tend to enter rooms where the sound from outside doesn't capture my interest—unless something really captures my eyes (or I'm required to for an assignment).

Also, when I listen at home I usually close my eyes, especially for critical listening. So at that point, the aesthetics become irrelevant. BUT I prefer and enjoy having components that appeal to my visual/aesthetic sense as well; I'm living with them in my space and would simply rather have something attractive around.

Jack L's picture

Hi

Why not? Just like stylish furniture - lifestyle. Nobody can challenge it.

But my point is: sound always comes before the exterior design of the product. For yours truly, it is the sound dicates me to choose the right one for my budget & exterior design is only the bonus which is always welcome.

Listening is believing

Jack L

Archimago's picture

Hmmm. I appreciate the mechanics. The VU meters look nice. Strong nods to the '70s vintage esthetics, but obviously more "flowery".

IMO, this is clearly overdone; reminds me of the overwrought CGI effects in some Asian (primarily Chinese) movies which lack finesse. Much of it just screams "appearance for appearance sake" which I guess is OK if one has an affinity to it and truly "love" that look.

I fear that this kind of look will not age well though. I would suggest to HiFi Rose that "less is more". Aim for elegance rather than risk looking tacky as they're doing right now with this (again, IMO).

It would be interesting to see in a poll if the general audio-loving public likes this front panel!

Archimago's picture

Figured I'd poll the folks over on Steve Hoffman Forums here:
https://forums.stevehoffman.tv/threads/poll-do-you-like-the-look-of-the-hifi-rose-ra180-front-panel.1161772/

Feel free to share your opinion!

Jack L's picture

Hi

Is such polling necessary ?????

Any audio designers want to put their personality signature on the front panel designs. This is its value & presitige & should not be challenged.

Anybody ever ever challenged of the beauty of Mona Lisa ?

Come on, get real !

Jack L

Archimago's picture

Since when was this device some kind of "fine art" where one is supposed to respect the creative integrity of the design team?

Of course the appearance can be questioned! When you look at that thing, does it look like form follows function? Or maybe just a little too much flight of fancy?

It's consumer electronics. Consumers have an opinion and in fact the final say as to whether they care for it. Nothing wrong with having a poll on it and in fact, I hope the design team made sure to engage some consumer market research to make sure this targeted the intended audience.

Jack L's picture

Hi

Mona Lisa is a priceless historic fine art which has been open for appreciation to the public at large in Palace of Versailles near Paris. I still recall my wife & I got to line up for an hour or so to to get a view of the small painting from a fence-off distance of some 15 ft !!!!

Any commercial design is still some art - applied art. It may not suit everybody who always gets its own preference & like.

Like coffee, many love black & yet many love double (milk)/double (sugar) instead. So do we need to get a poll on it?

Jack L

windansea's picture

Looks like an airline cockpit to me. I would have loved this as a child. But now I think it has too much surplusage and all I want is a power switch and volume knob.

But the active crossover and biamping option sound awesome to me. I love that idea. I've wanted to biamp my time windows with active crossovers but the expense and hassle have exceeded my limits. This all-in-one option could be perfect for me.

Julie Mullins's picture

There is a lot going on there: It's packed with knobs and switches. It does make kind of an "extreme" statement, but that's part of what makes it unique.

bhkat's picture

Front panel looks like the guy who designs Nagra equipment took some magic mushrooms before designing the front panel.

MontyM's picture

Hi Julie. The RA180 was set up in one of the rooms of my local HiFi store when I visited a couple weeks ago. I agree that the look and feel of the thing is great; a conversation starter for sure, if nothing else. Sonically, not my cup of tea, but visually it definitely stood out from the other integrated amps in its price range. I generally prefer a form follows function design aesthetic, but I certainly appreciate a bit of whimsy now and again. Thanks for the review.

Julie Mullins's picture

I generally prefer a form follows function design aesthetic, but I certainly appreciate a bit of whimsy now and again.

Although it is functional in its form: Almost everything is right there on the front panel. And I agree that a bit of whimsy in a hobby/industry that sometimes takes itself too seriously is a positive thing!

Electrophone's picture

I had the opportunity to manually operate the RA-180's interesting volume control mechanism at the local dealer and am disappointed that the process is not as refined as expected. The gears don't run as smoothly as expected at this price point, leaving the impression of under-engineering.

PeterG's picture

A fun description of a cool visual design, but the central question is left unanswered--how does the amp sound compared to competition? This is especially important when reviewing a Class D where conventional wisdom is that although they are more efficient/economical, they still cannot match A or AB for the serious listener

Julie Mullins's picture

Thanks for commenting, PeterG. In part because this differs from a "typical" Class D amp in that it's built around more modern Gallium Nitride (GaN) transistors rather than silicon ones, I decided to talk about those sonic differences (and benefits) rather than focusing on direct comparisons or doing a "shoot-out." Also, I've only heard a few other GaN-based amps, such as the Technics SU-G700M2 integrated amp (and only briefly, at a show or two) that use GaN transistors—something I'd mentioned in an earlier draft of this review (that didn't appear in the final version).

windansea's picture

keep writing these excellent reviews-- they are a breath of fresh air with zero snootiness and plenty of relevant observations for those of us considering whether to purchase the reviewed product.

Julie Mullins's picture

I appreciate your kind words. More to come...

PeterG's picture

Thanks, Julie. I guess we differ on the definition of competition. I am agnostic wrt architecture--I do not really care too much if an amp is A, AB, D, tubes, SS....But I care A LOT about an amp compares to other amps in its general price range. (BTW, I think we had a similar exchange on the marble(?) speakers you reviewed a few months ago) Rock on!

Julie Mullins's picture

You make a fair comment. I'm also "agnostic" in the sense that I don't have a strong bias (pun intended) for or against tube amps or various solid-state types or topologies. Because I don't have a wide array of amps on-hand (just a few), I'd be going mostly from memory.
It's another good reason for me to keep visiting dealers, attending audio shows, checking out friends' systems, etc. to hear as much new and different gear as possible and keep staying up-to-date.
(BTW, those other speakers I reviewed that you mentioned were made of granite, made by Acora Acoustics.)

Glotz's picture

The review, of course.

Will you or another reviewer report on the Mytek Empire Monoblocks? GaN-based amplifiers are very intriguing...

mns3dhm's picture

This is a component that, should a friend buy one and ask if I'd like to listen, I'd be 'shit yeah!'. I would probably wind-up annoying said friend by asking them to run through its myriad of setup and operational options. Kinda the opposite of straight wire with gain. Thanks for the review.

Jack L's picture

Hi

Agreed ! Who needs thousands of watts for decent music let alone the musicality of Class-Ds ? I don't & would never !!

FYI, my humble dirt-cheap home-brew zero local/global NFB class-A SET delivering only 5W per channel working hand-in-hand with 3 x100W active subwoofers (L, R, L+R) can deliver 103db(C) SPL musicality nooo sweat !

Be smartly ahead of the game !

Listening to class-A SET is believing

Jack L

barfle's picture

Like others, I’m reminded of a Nagra deck. Lots of meters and buttons and knobs, and I certainly appreciate design, but it might be a bit much and might not age well. But very, very groovy.

barfle's picture

Like others, I’m reminded of a Nagra deck. Lots of meters and buttons and knobs, and I certainly appreciate design, but it might be a bit much and might not age well. But very, very groovy.

barfle's picture

Like others, I’m reminded of a Nagra deck. Lots of meters and buttons and knobs, and I certainly appreciate design, but it might be a bit much and might not age well. But very, very groovy.

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