Rotel's range-topping home theatre components amp up their audio antes to new heights
By Jim Bray
It's been over two years in development, but Rotel's new surround sound preamp/processor was definitely worth the wait. And if you couple it to the brand's top end five channel power amplifier, you may find it a match made in audio/video heaven.
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I certainly did, not that I'm surprised. Some years ago, I fell under the spell of Rotel's then-top of the line preamp/surround sound processor, the RSP-1098. It was bigger than many receivers, offered state-of-the-art audio and video features and specifications for its day and, best of all, had glorious sound - like every other Rotel component I had tested till that point but on an even higher plane.
Since then, the company has offered some very good preamps, including the still available RSP-1572 I reviewed here back in 2013. These new units embrace today's technological advances, such as HDMI, 3D, high definition TV and the new lossless sound formats, and they do an excellent job.
The new RSP-1582 is all that, only more. I've been using it for a couple of months now and, if you want to cut to the chase, I like it as much - or more - than the 1098 it replaces. It is truly spectacular from an audio perspective, which is my priority in such equipment, and the rest of its many features add to the unit's overall value.
One of the things that denotes the 7.1 channel-capable RSP-1582's higher end mien is the inclusion of balanced outputs, which are professional grade connections that up the voltage of the output signal. What it means to your ears is that if you thought the system played loudly with the normal RCA connectors, you may be in for a real treat. Or be blown out of your listening room…
A preamp/processor still needs an amp, of course, and since the RSP-1582 is all new, I figured it would make a better test if I tried it with Rotel's latest five channel amp, the RMB-1585. It's a hefty Class A/B amp rated at 200 watts x 5 and coupling the two components together creates the best current Rotel-powered setup one can get. And it's an awesome package!
To help ensure I the fairest review possible, I left the new amp in its substantial packing case for a few weeks while I ran the preamp through my outrageous 500 watt per channel Class D Rotels. The RB-1091 and RB-1092's (I use two stereo and one mono amp to create five channels) are wonderful performers, though they're also a bit of overkill for my small suburban basement home theatre. But what glorious sound!
Once I'd given the preamp a chance to perform for a while with the Class D amps I replaced them in the stack with the RMB-1585 to see how both new components fared.
The Head Unit…
Rotel has been in this business for a long time, making its reputation over the years with fine audio equipment, so even though the company has added prodigious video capabilities to its home theatre equipment, its focus on sound quality still permeates the line. As it should.
The $3899 CAD RSP-1582 processor, available in silver or black, was crafted for highest performance and maximum flexibility - and other than the lack of automatic room equalization (you do get a built in parametric equalizer, however) I can't think of anything they could add. Heck, the thing even has 4K video pass-through capability in its eight HDMI ports.
To ensure optimal audio, the RSP-1582 uses a sextet of high performance Wolfson 24 bit, 192 kHz digital to analogue converters, a Texas Instruments Aureus TMS320DA808 DSP high-performance decoder with 10 channel parametric equalization and a PCM1804 audio performance analogue to digital convertor. If you prefer having your source device do the decoding you can use the 1582's bypass function to basically route the analogue signal right through the preamp and back out to the amp with no further processing. And a "multi" connection lets you hook in the 7.1 channels of your source device via analogue connection. This is my preferred method of connection, but to each his/her/its own.
On the video side of things, the RSP-1582 uses a Silicon Image Sil9573 2K/4K HDMI transceiver.
An interesting touch is the seven inch LCD on the unit's front - something Rotel also did with the old RSP-1098. The LCD is a wonderful way for you to scroll through the various menus and tweak the many parameters, using either the remote control or the cursor control buttons to the left of the screen, and it gives you a way to make your adjustments without having to turn on your TV to use the Rotel's on screen display.
This came in particularly handy in my installation, because I have a front projector and firing it up just to check the volume (or whatever) wastes valuable bulb time as well as adding fan noise from the projector. The only downside to this is that Rotel has used a small font for most of what's displayed on the LCD and these old eyes can't read it from their perch across the room on the Lazy Boy (that's me, not the couch). To solve this, I output the RSP's display to a 24 inch LCD flat panel on the floor in front of the electronics stack (the processor will feed two HDMI destinations) and that works great.
You can hook pretty well any type of digital device into the RSP-1582, a testament to its flexibility. It includes inputs for PC-USB (supporting 24 bit/192 kHz audio files), a turntable, CD, tuner, four auxiliary inputs and the abovementioned multi-channel analogue inputs. You can update the firmware via a wired network connection or via the USB input (using a USB "thumb drive"). The rear panel also includes three optical and three coaxial digital inputs.
The front panel HDMI input is great for temporary hook ups, such as a camcorder, and there's also an iPod USB input with charging capability on that panel. They've even integrated APTX Bluetooth, so you can stream tunes wirelessly from your phone or other such device - and pairing your device is child's play.
Outputs include the abovementioned XLR balanced and RCA unbalanced ports, as well as dual subwoofer jacks. There are also three source independent trigger outputs, a wired IR remote input, RS232 interface and IP network interface for home automation system control. Heck, it even comes with "ears" for rack mounting.
Here are some of the relevant specifications of the RSP-1582:
Total Harmonic Distortion (THD)
(20Hz - 20kHz) <0.005%
Analog Bypass: 10Hz - 100kHz ±1.5dB
Digital Inputs: 10Hz - 20kHz ±0.3dB
S/N Ratio (IHF "A" Weighted)
Analog Bypass: 112dB
Digital Inputs: 112dB
Video Input Resolutions
480i, 480p, 576i, 576p, 720p, 1080i, 1080p, 1080p/24Hz, 3D, 4K, UHD
Video Output Resolutions
480i, 480p, 576i, 576p, 720p, 1080i, 1080p, 1080p/24Hz, 3D, 4K, UHD
Decodable Digital Input Signals
Dolby TrueHD, Dolby Digital, Dolby Digital EX, Dolby Digital Plus, DTS HD Master Audio, DTS HD, DTS, DTS-ES, DTS 96/24, DTS-ES 96/24, LPCM up to 192kHz
Version 1.4, support up to 4K resolution pass-through and Audio Return Channel
One of the first things I noticed in my listening tests was not just the beautifully clean and lifelike sound emanating from the Rotel, but also its incredible sound stage and channel separation. When I fired up the 5.1 DVD-Audio mix of Emerson, Lake and Palmer's "Brain Salad Surgery," which throws stuff from speaker to speaker all around the room, it was almost as if it were the first time I'd heard that version - instead of perhaps the 100th. Ditto for the DVD-A surround versions of "Machine Head," "Hotel California," "The Captain and Me" and Les Brown and his Band of Renown's "Session # 55." The surround versions of the "Every Good Boy Deserves Favour" and "Dark Side of the Moon" SACD's sounded equally spectacular.
I found myself digging out high resolution discs and other sources that I hadn't played for ages - including the 5.1 mix of "L.A. Woman" as well as some Strauss, Beethoven and Sinatra. Such was the elevated level of the RSP-1582's audio performance that it revealed nuances in the music that I'd never heard before; it was like going back in time to the first audiophile components I tried many years ago, when I discovered that there was plenty in the material that the lower end stuff just can't reproduce. For example, during quiet passages of the Beethoven's Ninth, you could hear clearly some of the musicians shifting position in their chairs before attacking the next segment.
It isn't just the channel separation and sound stage that excel, of course. The bass - I ran the crossovers at 100 Hz - is tight and deep and clean, the midrange is open and extremely detailed and the high frequencies are very transparent.
Naturally, the processor works the same magic with movie soundtracks. It doesn't handle the new Dolby Atmos or DTS X formats yet, but not much else does yet, either. I ran some favourite movies through the system, such as Avatar and Fifth Element (which have excellent surround soundtracks) and they sounded richer and fuller than they had before - and they sounded great before.
A thousand watts of oomph…
Remember, these observations so far were made while using my 2007 vintage Class D amplifiers. Things got even better when I swapped them out for the RMB-1585. The Class A/B amplifier puts out less than half the power I'm used to but it didn't take me long to forget about that and revel in its wonderfully warm and open audio performance, especially once I switched from the RCA's to the balanced connections.
Two hundred clean watts per channel, into five channels, should be more than adequate for the lion's share of home theatres, listening rooms, and speaker systems and the heavyweight (it tips the scale at 79 pounds!) RMB-1585 certainly proved more than adequate in my home theatre. Any louder and I'd have to get divorced!
The amplifier sounded fantastic right out of the box, without any break-in period other than a couple of hours of stereo pink noise I ran through it. To ensure an apples-to-apples comparison, I went back to much of the same listening material I had used while auditioning the RSP-1582 with my older amps, and I came away from my sessions confident that the RMB-1585's 200 watts is actually a better match for my listening room than my Class D's. It puts out wonderfully warm and clean sound, with a broad and full soundstage whether you're listening to stereo or surround, whether it's loud or quiet.
The stereo soundstage is so broad and deep, and with such pinpoint placement of instruments, that when I played a stereo SACD of an album I haven't listened to in a looong time the music filled the room so beautifully that, at various times during the album, I found myself getting up to check and see whether the surround and/or centre speakers were on, since the processor can convert two channel stereo to various surround modes and I thought I might have activated one by mistake.
I hadn't. The sound was coming only from my pair of Definitive Technology towers. It was remarkable!
Instruments often sounded as if they were coming from beyond the rear wall of the listening room, or outside the side walls. It was an extraordinary listening experience, and while I thought initially that the amp wasn't as loud at the same volume as my old ones are, my sound pressure level meter proved me wrong. At one point when I had it really cranked, playing the 5.1 SACD of "Dark Side of the Moon," the meter peaked at 102 dB, which is undoubtedly why the cats had hightailed it upstairs and were nowhere to be found…
Here are some of Rotel's relevant specs for the amp:
Continuous Power Output
200W/Ch (All channels driven, 8Ω)
Total Harmonic Distortion (THD)
(20Hz - 20kHz) <0.03%
10Hz - 100kHz +0.5, -3dB
S/N Ratio (IHF "A" Weighted)
Intermodulation Distortion (60Hz:7kHz, 4:1)
Line Level Inputs (RCA): 1.9V
Line Level Inputs (XLR): 3.8V
Line Level Inputs (RCA): 12kΩ
Line Level Inputs (XLR): 100kΩ
The $3199 CAD RMB-1585's power button features Rotel's obtrusive bright blue ring around it (as does the RSP-1582). It's too bright - you can almost read by in a darkened room - but the company includes stickers you can use to cover the blue rings, though I've never bothered with them. On the amp, the lighted ring also serves as a flashing warning if its protection circuitry kicks in (which has never happened to me), so it's probably best not to hide it anyway.
The rear panel hold the connectors from the preamp, as well as the speaker outputs. There are also trigger ports and a three position switch for the built in fans; the switch defaults to "low" and I left it there, with no excess heat or fan noise issues.
Rotel uses a huge power supply with twin toroidal transformers and high end slit foil capacitors as the heart of the amplifier - as is their wont - and as their wont it really pays off. The RMB-1585 seemed to hit my speakers' sweet spot, reminding me once again why I'd bought them in the first place. And they responded happily, as if asking "is that all you got?"
As usual, I began with a digital file of the remastered "Live at Leeds" by The Who, kicking things off with the final cut "Magic Bus," one of the most dynamic recordings I have, even though it was made in 1971. It's only stereo, but thanks to the Rotel pair's exquisite soundstage, it was almost as if I were there except that no one was spilling beer over me (I had to do that myself).
The first movie I tried with the amp in the mix was Pixar's "The Incredibles," which has a dynamic soundtrack that can practically blow you out of the room if you crank it. I did, and it nearly did. It was great!
There's more to good sound than playing loud enough to make ears bleed, of course, and this particular pair of pieces performs beautifully at volumes across the spectrum. To rip off Neil Diamond, it's a beautiful noise that brings out every nuance of the source material. It didn't matter if it was classical music, jazz, rock, spacecraft, gunfire, explosions or whatever - the amp handled the noisy stuff as it was born to, with marvelous bombast and fidelity, while the quieter and more serene stuff - background sounds, quiet musical passages, whatever - were reproduced faithfully, with a lack of background noise or other artifacts.
In an era in which society seems to be slouching toward the lowest common denominator, it's nice to see a company that still pursues excellence. And now that I've lived with the RSP-1582 preamp and RMB-1585 amp, I don't think I can go back to the RSP-1572 and my Class D powerhouses. It isn't as if the RSP-1572 is a slouch - it isn't, by any means - and while I thought I'd miss the extra power of the Class D's, I don't: the RSP-1582 and RMB-1585 combination simply raises the bar to the next higher level of performance.
It's kind of like the difference between a Nissan 370Z and a Porsche Cayman: while there's absolutely nothing wrong with a Z - I owned a 240Z once and loved it - once you've driven a Porsche there's no going back. So it is with the RSP-1582 and RMB-1585: I've been completely happy with the RSP-1572 and my Class D amps and would have continued being perfectly happy with them had I not spent time behind the wheel of the 1582/1585. And now I'm spoiled.
It's true that to purchase both of these pieces you'll need to shell out about seven grand Canadian (and remember, you can spend a lot more than that on other high end equipment), but if you can justify that amount, you'll be rewarded handsomely. And since the components are virtually state-of-the-art, they should last you as long as you want or need them to.
Copyright 2016 Jim Bray
Jim Bray's columns are available through the TechnoFile Syndicate.
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