As a native son of Pennsylvania, I was thrilled when I learned that I would be reviewing Rogue Audio’s new RP-5 tubed preamplifier ($3500 USD), as soon as a sample was available. Rogue is based in Brodheadsville, 90 miles north of Philadelphia and about an hour from where I live. As sports fans, Philadelphians are typically long-suffering but devoted. With that as my background, it would be easy to be a fan of a local audio company. However, Philadelphians’ familiarity with recurring heartbreak has taught us to view everything with a critical eye. I anticipated the arrival of a new audio component, full of hope that it would live up to the fine reputation of Rogue’s other US-made products. What arrived surprised me in several ways.
First, the RP-5’s shipping carton was big enough to hold a midsize power amp. At 18.5”W x 4.5”H x 14.5”D, the RP-5 is notably larger than my reference, solid-state preamp, a Hegel Music Systems P20 ($2900), in all three dimensions. It’s also heavy -- 30 pounds -- and feels solidly built. All of which made removing the RP-5 from its box a bit more work than I’d anticipated. Rogue had sent me an all-silver version -- the RP-5 is also available in all black. In contrast to many designs, my sample was actually silver on the front, top, and side panels -- a nice change from the usual silver faceplate fronting a styleless black box.
At the center of the RP-5’s faceplate is a large, black oval containing a two-line alphanumeric display, its blue characters easily readable. To either side of this is a large knob: Balance on the left, Volume on the right. Between and below these is a row of pushbuttons. From left to right, these are: Balance on/off, Processor Loop, selectors for the four line-level and one phono input, Mono/Stereo, and Power. “Rogue Audio” is tastefully engraved in the lower left corner, complemented by a 1/4” headphone jack at lower right. All controls and their actions had a high-precision feel to them. Overall, the RP-5’s build quality was very high.
Powering up the RP-5 resulted in the satisfying clicking of several relays within. The display lit up and ran through a 30-second countdown, to allow the RP-5’s four JJ Electronic 12AU7/ECC82 tubes to stabilize. That done, the screen displayed the input selected and the relative volume level, the latter in a range of “00” to “60.” An LED over the selected input button also glowed.
Turning the Balance knob changes the display to indicate the deviation in -dB relative to the volume number for the other channel, or vice versa, and lights up the Balance LED. Re-centering is easily accomplished by pressing the Balance button, which also extinguishes the Balance LED. The indicator lights glow a gentle, pleasant blue that’s a slightly different shade from the blue of the display, which irritates the overparticular stylist in me. A subtle detail, to be sure.
I had no record player to plug into the RP-5’s phono input. But if I did have one, the RP-5 could accommodate virtually any cartridge, moving-magnet or moving-coil. Its clearly written manual provides illustrated instructions for all of the various adjustments to make in matching a cartridge. Changing these settings requires opening the case and setting a variety of DIP switches.
I used my trusty Bowers & Wilkins C5 headphones to assess the RP-5’s tubed headphone amplifier. My recent experiences with preamps that provide headphone output have resulted in a lot of mediocre sound, but here was another way in which the Rogue surprised me. Its headphone sound was quite good: neutral, and similar in quality and clarity to the headphone output of my Benchmark DAC2 HGC. I suspect that most users of traditional preamps use headphones only under duress. In the case of the RP-5, your satisfaction with its sound won’t be diminished if you have to switch off your speakers and plug in your cans.
The RP-5’s rear panel is laid out cleanly, with plenty of room for thick interconnects: high-quality, gold-plated, single-ended inputs and outputs (RCA) abound. Someone at Rogue Audio said that the RP-5’s circuitry is purely single-ended. Other Rogue models, including the upcoming RP-7 preamp, offer balanced connections as well. Most of the rear panel is occupied by rows of stacked pairs of connectors: left channel on top, right channel below. From left to right are: the Phono input and Phono Ground, a blank area, and then two sets of volume-controlled outputs, the HT Bypass, Processor Loop ins and outs, Fixed outs, four Line inputs, the main Standby switch, a fuse bay, and a three-pronged IEC inlet for the detachable power cord.
My setup for best-quality listening was easy: my Apple iMac, running iTunes, was connected via USB to the Benchmark DAC2 HGC. Interconnects from the Benchmark to the Rogue and from the Rogue to my Audio Research D300 power amp were single-ended RCAs. General control of the preamplifier was handled by its nicely functional, all-plastic remote control, whose ten buttons are: Power, Volume +/-, Mute, Input +/-, Processor in/out, Balance Left/Right, and Mono. During my listening, I found that the IR signals used by the Rogue’s remote are the same as those used by my Hegel P20’s remote. This led to some interesting switching challenges, as I tried to shut one preamp down while leaving the other on, to avoid having to wait through the startup cycle of either. I did a bit of waiting. I expected a more robust-feeling remote with a $3500 preamp, but Hegel’s all-metal handset has set the bar high.
Another surprise: The RP-5 didn’t obviously sound like a tubed preamplifier. In the past 30 years I’ve enjoyed listening to music through various types of systems, gradually moving from an initial preference for solid-state to having some tubes in the system, and then a recent shift back to transistors. The sound of the RP-5 was closer to neutral than most tubed gear I’ve used.
On a recent plane flight, I watched Interstellar. Despite the poor setting in which to experience a film -- a plane’s sound system is never good -- I decided while watching that I needed to get a copy of the soundtrack album. Although I’d found Hans Zimmer’s music entertaining over the background roar of the Airbus’s engines, I later discovered that it was an awesome composition. I’d spent a few dollars over the CD price to get the high-resolution version (24-bit/44.1kHz AIFF, WaterTower Music) from HDtracks. Though the music is generally subdued, I find it riveting, with many complicated nuances. One of my favorite tracks, “No Time for Caution,” begins slowly with lingering, airy, somewhat typically “spacey” higher-pitched tones over a deep rumble that was firmly presented by my Paradigm Prestige 95F speakers. Percussion enters, a woodblock “clock” and remote church bells rapidly marking time. Then a pipe organ joins in, stridently playing the recurring theme. Quieter percussion sounds enter and exit at irregular intervals. Massed strings, first plucked, then bowed, join to create a final grand statement. Played loudly, the thunderous roars that mark the climax of this track’s volume and excitement were stunning through the RP-5. The “clock” effect marking the final organ swell slowly faded to silence, the decays perfectly reproduced by the Rogue. At no time during all of this did the RP-5 misstep. There was an ease to its sound that let me isolate and quickly identify any of the various instruments comprising the overall sound of this complex mix, in which the sounds of acoustic instruments and electronics were placed all over the stereo soundstage. I could easily locate each instrument through the Rogue and, when the instrument was acoustic, just as easily identify what it was. The soundstage was broad and deep, extending beyond the Paradigms’ outer side panels.
“Day One,” a subtler selection from the Interstellar score, is mostly piano over strings, with uncomplicated electronic tones and sounds. The melancholy feel of this track is almost palpable. I was struck again by how easily identifiable each instrument and sound was, yet felt that everything was still being presented as a part of the whole; nothing was isolated in an unnatural way. While electronic in composition, the music sounded less digital through the Rogue. Perhaps this had to do with the recording’s 24-bit resolution, but I believe it also had to do with the Rogue’s ability to allow the sound to flow easily.
I stayed with higher-resolution selections but switched to solo piano. I have an “open” recording of J.S. Bach’s Goldberg Variations, BWV 988, performed by pianist Kimiko Ishizaka (24/48 AIFF, Open Goldberg Variations). The recording, a crowd-funded Kickstarter venture, has been released with a Creative Commons Zero License, which means, according to the site, that it is “part of the public domain” and “free of copyright (all uses allowed).” The price? “Pay what you want,” including nothing at all. (See opengoldbergvariations.org.) Ishizaka plays a Bösendorfer 290 Imperial piano. The sound of that model, let alone this specific instrument, is beyond my knowledge, but I can tell you that, through the Rogue RP-5, it sounded rich and tonally dense. The recordings were made at the Teldex Studio, in Berlin, Germany. Photos taken during the performance show that the studio is a large space in which significant efforts seem to have been made to eliminate wall and ceiling reflections. The sound through the RP-5 was very smooth, without the harshness at the top of the instrument’s range that is often heard in solo-piano recordings. The Rogue rendered the Bösendorfer’s entire range uniformly, without the midrange bloom often heard with tubes.
Chicago’s 17th album, imaginatively titled 17 -- the band is now up to XXXVI -- was first released in 1984 (16/44.1 AIFF, Rhino). The horn section was then still putting out some nice swing, as in “We Can Stop the Hurtin’,” as well as some guitar funk, all sprinkled with modest use of 1980s keyboards. A high-paced rhythm guitar cycles all the way through the track and gives it a feeling of constantly pressing forward. But even with all of the ’80s glare of its CD mastering, this recording is still great fun. Nothing the RP-5 did made me want to analyze the sound for flaws -- instead, I bobbed my head and tapped my toes. Nonetheless, I could still focus on individual instruments, as I had with the Interstellar tracks. Overall, the sound was slightly softer than I remember it from the many times I’ve played this album through my reference Hegel P20. If the Rogue RP-5 had a sonic signature, it was a very slight softness.
“Another Record,” from Genesis’s 1981 album, Abacab (16/44.1 AIFF, Atlantic), is of the same era as Chicago’s 17 but better recorded, with a fuller sound and a wider dynamic range. This song boogies just as well as “We Can Stop the Hurtin’,” though -- it gets my body moving. The Rogue removed nothing from this track, just letting let the music’s drive flow unimpeded.
As long as I was stuck in the 1980s, I felt compelled to put on “the song from that GMC truck commercial at the baseball stadium.” More specifically: “Eminence Front,” from the Who’s 1982 album, It’s Hard (16/44.1 AIFF, MCA) -- yet another song with a driving theme that runs from beginning to end and stitches the whole thing together. In this case, it’s the catchy keyboard bit that has got stuck in people’s heads over the last few months of GMC’s ad campaign. John Entwistle’s bass line also adds some nice funk. I found myself not worrying about how great the sound of the Rogue was, or how mediocre the recording was, though both were the case. The RP-5 kept me firmly focused on the music, instead of picking out this or that trait to zero in on.
As soon as I fed the Rogue its first few tracks, I wished I still had on hand the Cary SL-100 preamplifier ($1995). Based on my mental and written notes, the tubed Rogue RP-5 sounded, surprisingly, slightly less tube-like than the solid-state Cary. The two share a fun musicality that was very engaging -- with both, I found it difficult to tear myself away from my music and get back to real life. But there were other differences: The Cary’s sound was more laid-back overall, while the Rogue’s was essentially neutral if slightly laid-back. The RP-5’s sound was never in my face, but it also never felt distant. The Rogue produced wider soundstages that did not wander between the speakers; the Cary’s soundstaging was slightly reserved by comparison.
Rogue Audio’s RP-5 surprised me. It did not have the fat, warm sound associated with vacuum tubes. It exhibited no strong sonic signature of its own, which impressed me from the outset. I found it a fundamentally neutral and wonderfully musical preamplifier that would easily be at home in an all-tube system, or one in which it’s mated to solid-state gear. In my estimation, the RP-5’s neutrality should make it an easy partner for just about any system. Rogue makes this statement on their website: “Our philosophy is simple -- We will never design any amplifier that we would not purchase for ourselves.”
From the evidence presented to me by this model, the folks at Rogue Audio like their equipment to sound great, look attractive, and feel satisfying to the touch. The RP-5 is a preamp that, I, too, would happily buy.
. . . Erich Wetzel
- Speakers -- Paradigm Prestige 95F
- Headphones -- Bowers & Wilkins C5
- Preamplifiers -- Benchmark Media Systems DAC2 HGC, Hegel Music Systems P20
- Amplifier -- Audio Research D300
- Source -- Apple iMac running iTunes
- Digital-to-analog converter -- Benchmark Media Systems DAC2 HGC
- Speaker cables -- Transparent MusicWave Ultra
- Interconnects -- AudioQuest King Cobra (XLR) and Ruby (RCA), Dynamique Shadow (XLR), Transparent Audio MusicLink Super (RCA), generic TosLink (optical), Monoprice USB
Rogue Audio RP-5 Preamplifier
Price: $3500 USD.
Warranty: Three years parts and labor; six months, tubes.
PO Box 1076
Brodheadsville, PA 18322
Phone: (570) 992-9901