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Rotel, originally founded by Tomoki Tachikawa under the name Roland, broke into the electronics industry in the 1950s as a Japanese distributer of US-made Sylvania television sets. Due to the higher voltage standards employed on the far side of the pond, distributing Sylvania’s products, at the time, meant that Roland was also responsible for both modifying and servicing said products to meet local requirements. As a result, engineering quickly became a mainstay of Roland’s business plan, and eventually led the company away from distribution and into manufacturing. In 1961, Roland became Rotel, and continued to focus on manufacturing quality electronics until the late 1960s, at which point they began designing and manufacturing products for other audiophile-oriented companies as well as under the Rotel brand name. In 1973, Rotel earned its first Consumer Reports “Best Buy” award for their hugely popular RX-402 receiver -- and the rest, as they say, is history.

Rotel RMB-1585

I first took note of Rotel shortly after the launch of the company’s 10 series. I had a penchant for imposing-looking high-end gear, was in the market for an amp that could do double duty for music and movies, and Rotel’s then-flagship multichannel amplifier, the five-channel RMB-1095, seemed to fit the bill. It had massive vertical heatsinks over 9” high, tipped the scales at just over 75 pounds, and put out 200Wpc, all channels driven into 8 ohms, 20Hz-20kHz, with less than 0.03% THD. I was sold at first listen. The RMB-1095 was manufactured from 2000 to 2008; then, in 2009, Rotel rolled out their 15 series, which eventually included the RMB-1095’s successor and the subject of this review: the RMB-1585.

The beast beneath

Rotel’s RMB-1585 ($2999 USD) is every bit the muscular, 200Wpc beast its predecessor was. It stands 9 3/8” tall, is 1/8” less wide than the RMB-1095 at 17”, but at 17 7/8” deep is almost 3” deeper, and weighs a beefy 79.3 pounds. The RMB-1585 also has an entirely new look that reminds me a little of Krell’s popular Showcase series in its rounded, polished corners of solid, CNC-machined aluminum, and flat, clean faceplate. Available in black or brushed aluminum, that faceplate is unmistakably Rotel -- on it are only a brightly lit, flush-mounted Power button in the upper left corner, and Rotel’s logo stamped deeply into the surface about an inch from the top edge.

The rear panel is horizontally divided into fourths: at top are five balanced (XLR) and five unbalanced (RCA) inputs; below these, flanked by a pair of exhaust fans, are a 12V trigger in/out bay and the master power toggle; below these are five high-quality binding posts easily capable of accepting speaker cables terminated in spades, bananas, or bare wire; and, at bottom, a row of small ventilation slots and, at far right, an IEC outlet. A bulky rubber bumper is placed in each corner of the panel to ensure that the terminals won’t be damaged if the amplifier is upended, or pushed against a wall or the back of a cabinet. Unfortunately, Rotel has seen fit to do away with the handy wheels that replaced the rear feet of the RMB-1095; their absence made positioning the RMB-1585 a bit more tedious.

Rotel RMB-1585

Removing the generously ventilated, one-piece cover of stamped and folded steel revealed the RMB-1585’s neatly organized innards, and made obvious the attention Rotel has lavished on cooling. Each heatsink has its own ventilation slots. The RMB-1585 monitors the temperature of its heatsinks; should they exceed a predetermined temperature, the cooling fans come on automatically, to quietly pull air through all vents and cool things down.

Necessitating all this cooling are three pairs of high-current power transistors per channel, fed current by two 535VA toroidal transformers, potted, stacked, and wired in parallel. Dynamic power demands from each of the RMB-1585’s 30 transistors are handled by eight 80V, 15,000µF slit-foil bulk storage capacitors, made in the UK by BHC Aerovox. Rotel makes use of slit-foil caps in all of their 15-series amplifiers; they believe that such capacitors minimize the eddy currents that typically reduce a conventional cap’s ability to efficiently store and supply energy. Collectively, these components enable the class-A/B RMB-1585 to produce a rated power output of at least 200Wpc, or a total of just over 1kW, all channels driven into 8 ohms. While, on paper, the RMB-1585’s damping factor of 260 is a good bit lower than the RMB-1095’s 400, Rotel explained to me that this is primarily due to a change in the way they measure this specification, and that the RMB-1585 provides similar if not greater levels of control over the speakers it drives. Rotel also told me that while they don’t specify the RMB-1585’s output into 4 or 2 ohms, it’s fully capable of driving speakers of such impedances, and that its output into 4 ohms is >300Wpc. The RMB-1585’s specs for total harmonic distortion (THD) and intermodulation distortion (IMD) are both <0.03%, and its signal/noise ratio is a respectably quiet 116dB, A-weighted. Its specified maximum gain is 26.5dB.

Setup

I evaluated the RMB-1585 with both music and movies. Normally, I use a multichannel amplifier to drive a Dynaudio Confidence center-channel speaker and four Bowers & Wilkins CWM 7.4 in-wall speakers, supplemented by a pair of Simaudio Moon Evolution W-7M monoblocks driving my Rockport Technologies Atrias, as well as two JL Audio Fathom f112 subwoofers, to comprise a 7.2-channel array. For the purposes of this review, I removed the W-7Ms, downsized my 7.2 channels to 5.2, and used the Rotel to drive the remaining five speakers, which for films hand off to the JLA subs at 80Hz. A Simaudio Moon Evolution P-8 preamplifier served as the center of my setup for music; for movies, I used a Marantz AV8801 A/V processor, connected via the P-8’s home-theater bypass. An Oppo Digital BDP-103D universal Blu-ray player, and a Dell Ultrabook computer feeding a Wadia di322 audio decoder via a Clarus Crimson USB link, respectively served as sources for movies and music. Powering the system was a Torus AVR2 power conditioner, and linking it all was a web of Clarus Crimson interconnects and Kimber Kable Select 6063 speaker cables.

Music

From my first listen to the RMB-1585, I could tell that its character was decidedly different from its predecessor’s. Where the RMB-1095 leaned ever so slightly toward the cool side of neutral, the RMB-1585 put forward a more fulsome sound, with levels of warmth, richness, and tonal color I hadn’t expected. Listening to “Wicked Game,” from Chris Isaak’s Best Of (16-bit/44.1kHz, FLAC, Reprise), I was treated to a fast yet deep, full, impactful bass line. Rowland Salley’s every pluck of bass string had satisfying punch, followed in perfect tempo by Prairie Prince’s quickly rendered yet easily envisioned brushes on the skins. James Wilsey’s seductive electric guitar dripped tonal color, and endlessly decayed into what seemed an infinite background. Normally, when I listen to “Wicked Game,” only three things really draw me in: the punchy bass line, Wilsey’s emotionally expressive guitar, and Isaak’s voice. Through the RMB-1585, I heard more and appreciated more, and was impressed by the precision with which each item on stage was painted. As I listened to this track, and others from various genres, these endearing qualities continued to emerge; I was pulled deeper and deeper into the precisely articulated soundstages presented by the RMB-1585.

Rotel RMB-1585

The RMB-1585 seemed capable of bottomless depths of power and control. Listening to “Locked in the Trunk of a Car,” from the Tragically Hip’s Yer Favourites (16/44.1 FLAC, MCA), the cymbals that begin the track sounded airy, light, and delicate. Quickly thereafter, Gord Sinclair’s bass kicks things into action, and kick really describes Sinclair’s bass, which had plenty of it through the Rotel, particularly when pitted against Rob Baker’s electric guitar. Gordon Downie’s voice occupies left center stage against Johnny Fay’s drums slightly to the right, and I was impressed by their pitch, density, and definition in the Rotel’s reproduction of them, particularly having recently seen The Hip play this song in a gig of what I hope won’t be their last tour. I was also pleased by the space and bloom the RMB-1585 was able to provide with and between the instruments and Downie -- through lesser equipment, this track can sound a bit compressed.

Movies

Impressed by how well the RMB-1585 reproduced music, I moved on to movies. Director J.J. Abrams’s Star Trek Into Darkness is replete with power-amp torture tests that range from massively dynamic passages to subtle textural details. Few will argue with Abrams’s directorial abilities, and in chapter 1 the Rotel convincingly communicated such captivating moments as the Starship Enterprise rising from the depths of a sea, its engines roaring, then rocketing into the sky. A bit later in this chapter, Abrams successfully sets the film’s tone by providing its first nail-biter, as Mr. Spock (Zachary Quinto) detonates a cold-fusion device inside an active volcano on the planet Nibiru, and a chain reaction occurs in which erupting lava is transformed into ice. The sounds of the transformation, which resemble those of ice cracking under immense pressure, grow in intensity as the transforming lava comes closer and closer to the viewer. Through other amps, these noises can sound brash, compressed, and monochromatic, and, at the scene’s climax, can cause an amp to clip. Through the Rotel, I heard the full extent of the transformation -- the sound of the erupting lava being changed into ice completely engulfed my room without sounding shrill, compressed, or the least bit strained. Through all five speakers I could hear not only the immense sounds of cracking at the beginning of the transformation, but also the sounds of smaller veins of ice forming beneath them -- all was quite compelling.

Rotel RMB-1585

Later, just after Spock is successfully beamed out of the volcano and back aboard the Enterprise, Lieutenant Uhura (Zoe Saldana) asks to notify Spock that the cold-fusion device has successfully detonated. On completing that transmission, she throws her communications device against the control panel in front of her. Normally, the transient of the sound of this impact is unremarkable; through the Rotel, there was an authenticity to the sound of metal hitting glass that grabbed my ear. Saldana’s voice also sounded particularly authentic, prompting me to listen to the subtler details beneath it. To my surprise, when I listened a bit closer, I realized that I couldn’t hear her breath quite as easily as I’d heard it through other, more costly amplifiers, such as Parasound’s Halo A 51 (see “Comparisons”).

As I pressed on, listening for other nuances, signs of congestion or artificiality, I was relieved to hear this slight shortcoming overshadowed in a subsequent scene in which Spock scolds Captain Kirk (Chris Pine) for permitting the natives of Nibiru to see the Enterprise, even though this was necessary to save Spock’s life. Both men’s voices sounded clear, concise, organic, and chock full of tonal character, despite the fact that Spock was still wearing his space helmet. The authenticity of the sound of Spock’s voice as heard through his helmet brought me right back to where I’d been when I heard Uhura’s coms device hit the control panel -- as it had with that foley effect, the Rotel painted an absolutely believable aural image of Spock’s voice as filtered through plastic and metal.

As this chapter ends, the Star Trek theme appears in Michael Giacchino’s orchestral score, leading us into the opening credits. But before this happens, the Enterprise enters warp drive with an explosive rocketing sound. This is one of my favorite test scenes: the sound of the engines propelling the ship into warp drive often causes lesser amps to clip at high volumes. Not the brawny Rotel -- the shift into warp drive was handled with ease, sounding tremendously impactful and dynamic. Having warped, the Enterprise leaves behind a trail of small, twinkling plasma particles, and the details that accompany this are a perfect test of an amp’s ability to uncover microlevel details. The RMB-1585 did a fairly good job of reproducing the twinkling sounds of these particles, but lacked some of the sparkle I’ve grown to appreciate with other amps. Between this, and the slight lack of presence in Uhura’s breath, I was beginning to wonder if the very welcome warmth I’d so enjoyed from the RMB-1585 with music had become, with movies, its Achilles’ heel.

Rotel RMB-1585

I looked for other scenes in which I could find something lacking, overemphasized, strained, or otherwise out of place in the RMB-1585’s reproduction of them. I found myself splitting hairs. For example, in chapter 12, in which the Enterprise loses all power and is being dragged by gravity toward the Earth’s surface, the objects crashing all over the ship could have been presented with an iota more detail and openness, but those subtle shortcomings were more than made up for by the realism with which voices were reproduced, the focus and speed with which the sounds of falling objects rushed by, and the clarity and complete sense of ease with which massively dynamic scenes and impacts were conveyed.

Comparisons

Its price of $2999 puts the RMB-1585 in a very competitive market. In comparison to the RMB-1095, which sold for $1995 when launched, I believe the RMB-1585’s upgrade in quality is worth the increase in price, particularly if you’re looking for a multichannel amplifier that will work equally well with music and films. Between the two, bass quality was a wash, and while the RMB-1095 may be the slightly more detailed, the RMB-1585’s vastly superior thermal management, added control, and more accurate reproduction of tonalities more than made up for that missing last measure of detail.

Because of my preference for playing movies at rather zealously high sound levels, I’ve tried many multichannel amps since the RMB-1095, looking for a combination of excellent build quality, sustaining sound quality, substantial power reserves, and good thermal management, all at a price I can live with. At the more budget-friendly end of the spectrum, priced substantially below the Rotel at $899, I lugged an Emotiva XPA-5 Gen2 five-channel amp out of my upstairs system and did a side-by-side comparison.

On paper, the two models provide identical power outputs into 8 ohms, the Rotel offering lower noise. With music, the Rotel indeed provided “blacker” backgrounds on which it cast its aural images. Through the Emotiva, images sounded more compressed, more dry and bright and lean, with a less-well-defined bottom end. That’s not to say that the Emotiva isn’t a great amp -- at less than a G-note it’s a heck of a value -- but the Rotel outclassed it.

With movies, the Emotiva seemed more in its element. I was able to pick up on such microdetails as the twinkling of the plasma-trail particles, the scrapes and crashes of pieces of this and that falling against the inside of the Enterprise’s hull as she fell toward Earth, and the echoing of the famous computer noises throughout the film, all a wisp more easily than through the Rotel. Unfortunately, the Emotiva couldn’t cope with the most dynamic passages without clipping at higher volumes, such as when the Enterprise enters warp speed. And putting a hand atop each amp after watching Into Darkness was telling: the Rotel felt barely warm; the Emotiva was hot enough to have burned my hand, had I left it there for more than three seconds. So back upstairs went the Emotiva, where it resumed its duties powering a modest TV-and-ambient-music system.

For a few days recently, I had a Parasound Halo A 51 five-channel amplifier in my system. At $4500, the Parasound’s sticker price is 50% north of the Rotel’s, and not unexpectedly, it proved superior in qualities of both sound and build. Admittedly, the fight wasn’t fair: The Halo A 51 is armed with a 2.2kVA toroidal transformer, 40 bipolar output transistors, 164,000µF of capacitance, and is a true balanced, direct-coupled design with a claimed output of more than 250Wpc into 8 ohms, all channels driven.

Overall, the Parasound’s sound was more neutral, and it delivered that last iota of detail I was searching for, painted larger and more three-dimensional images, and had degrees of speed and control, particularly in the bottom end, that the Rotel couldn’t match. The Rotel fought back with a heavier, more impactful bottom end, richer tonal colors, greater image density, and a sense of ease almost on a par with the Parasound’s. That the $4500 Halo A 51 didn’t completely outclass the $2999 RMB-1585 in the way the Rotel had outclassed the Emotiva should not be overlooked.

Conclusion

I was pleased with how convincingly Rotel’s RMB-1585 managed to reproduce the warmth, tonal color, and three-dimensionality of music-only recordings while sacrificing little in terms of overall resolution, detail, space around instruments, and microlevel nuances. Such a balancing act is not easy for any amp to pull off, and the fact that Rotel has managed to produce a multichannel powerhouse with such an alluring list of sonic characteristics is an achievement at this price. The stout RMB-1585 proved equally appealing with movies, providing endless reserves of power, arresting dynamics, wicked levels of transient control, and rich yet well-fleshed-out voices, all painted on vast soundstages. With a build quality and industrial design that push envelopes at this price, and if you’re in the market for a five-channel power amp for south of $5000, Rotel’s RMB-1585 is a must-hear.

. . . Aron Garrecht
arong@soundstagenetwork.com

Associated Equipment

  • Speakers -- Rockport Technologies Atria
  • Subwoofers -- JL Audio Fathom f112 (2)
  • Amplifiers -- Emotiva XPA-5 Gen2, Parasound Halo A 51; Simaudio Moon Evolution W-7M monoblocks (2)
  • Preamplifiers -- Marantz AV8801, Simaudio Moon Evolution P-8
  • Digital-to-analog converter -- Wadia di322
  • Sources -- Oppo Digital BDP-103 universal BD player, Simaudio MiND music server
  • Cables -- Clarus Crimson digital, AudioQuest Coffee AES/EBU link, Clarus Crimson interconnects, Kimber Kable Select KS-6063 speaker cables, Cardas Clear Blue Beyond power cords
  • Power conditioner -- Torus Power AVR2 20A

Rotel RMB-1585 Multichannel Amplifier
Price: $2999 USD.
Warranty: Five years parts and labor.

Rotel of America
54 Concord Street
North Reading, MA 01864-2699
Phone: (978) 664-3820
Fax: (978) 664-4109

E-mail: marketing@bwgroupusa.com
Website: www.rotel.com