Review: Rogue Audio 99 Magnum Tube preamp


Category: Preamps

Having owned a Rogue Magnum 99 for half a year, I felt it was time to write a review to share with Audiogon readers.

The Rogue 99 ended up replacing my Sonic Frontiers SFL2 preamp. The SFL2 was my first tube preamp, purchased used, and the sun rose and shine on that SFL2 in my opinion. It opened a whole new world of sound, making my former solid state preamps sound dry, lifeless, mechanical & thin. I felt I had reached nirvana, and had no need to look any further.

Seeing what a tube preamp provided, I slowly explored tube amplifiers. This led me to acquire an Audio Research VT-100 Mk II, which, again, provided a quantum leap over the McCormack DNA225 I owned. I could say more, but this is a review of the Rogue, not the ARC.

Always looking to try things, I experimented with a couple of passive units. Although I became convinced that passives lacked the dynamics, bass, staging and meat-on-the-bones of an active device, they did show me that there was some veiling & loss of definition from the SFL2.

Stereophile, in Jan. 2003, had a review of the Rogue. I encourage you to read that review. Chip Stern compared it to the Blue Circle & the VTL 5.5 and loved it. Besides his many praises, I think the one that really struck me was his closing statement, "I can't imagine any preamp at this price whose performance even vaguely approaches that of Rogue's Magnum 99." From my experience, I think Chip was right on target. But I'm getting ahead of myself.

I was very intrigued with the Rogue, but since it was single-ended & my amp was supposed to sound better in balanced mode, I thought it would be a gamble. Nevertheless, I decided to buy the Rogue, sight unseen.

After a brief burn in, I was ecstatic, as the Rogue sounded so much better than my SFL2. And this is in single-ended operation into my balanced-design amplifier! It was clearer, possessed more body, even the bass was better. Chip Stern terms it dry, but I found the SFL2 much drier. I think he was so used to the VTL's bloated sound, that this comment was only by comparison. I don't think of it as dry. I think it has a live, full midrange, but without any bloat. Voices have a focused wholeness & an aliveness that I have yet to find in any solid state preamp.

There is a nice lateral spread to the soundstage and a decent amount of depth. There is a nice, tasteful projection forward of the speakers which sounds very natural to my ears. This conversative forwardness is far preferable to me, than the recessed presentation that some interpret as natural or preferable. Never did I find myself feeling the preamp as bright or forward. My speakers are B&W 802 Matrix 3, which are equipped with Northcreek outboard crossovers. You haven't heard the capabilities of these speakers until you hear them with the Northcreeks. They literally transform these speakers.

I had the opportunity to compare an ARC LS-16 Mk I, which is $3,495 retail, $1,100 more than the R99.

In comparison, the LS16 was drier, with less dynamics. Overall, it was less musical, with a subtle mechanical hardness, and there was less soundstage spread and depth. The bass was perhaps marginally tighter on the LS16, but the drive & punch was weaker. Looking at the tiny transformer in the LS16 makes one wonder. The Rogue has a beautiful liquid sound that is very present and palpable, but not at all bright. It is dynamic and alive, with better and punchier bass. The bass may not be the tightest, but it is sufficiently defined for me, and, boy, does it sound real and have guts to it.

The midrange is equally a strong point of this preamp. Voices have a clarity, a focus, a wholeness, and a palpability that give a realism to voices that so many preamps, including the ARC LS16, lack. Piano notes have superior attack, followed by a full, rich sustain of the fundamental, and a full, ringing, sonorous vibration that makes a pianist like me very satisfied. I find that many preamps don't sound this real on piano. Yeah, they may sound good, but they lack the realism & the depth & weight of the hammer strikes & the main vibration that the Rogue provides.

My experience with tube rolling in the Magnum 99 has shown me how widely the sound can be changed. The stock tubes are NOS Russian jobs, that are pretty inexpensive. They are very good tubes, however, with a good balance of definition & body. Having only 4 tubes, it is not overly expensive to tube roll. For a time, I enjoyed using two black base RCA 6SN7GT in the front position, keeping two Russians in the back, or mu-follower positions. The RCAs provided a fuller, burnished sound, but with somewhat less definition. For less than ideal recordings, this was a great combo. However, I recently changed to the Russians in front position, & new Electroharmonix in the follower position. This provides more definition & treble extension, at the expense of a slightly thinner, more accurate sound. Remember we are talking tubes here, so thinner does not mean thin.

Is the Rogue perfect? No, but what is? I think even more definition & an even more expansive soundstage is possible with very expensive tube units, and with very expensive transistor units, such as Rowland & Pass. The transistor units, however, do not provide you with that midrange. I don't like the fact that the mute button makes a slight pop when you disengage it, but this is minor. Perhaps JA's measurements were so-so, but who cares? I am of the firm belief that more simply executed designs that do not measure perfect often end up sounding more natural and real to the music. If you're hung up with channel separation, blah, blah – do yourself a favor & get over it. It means so little compared to how the piece makes music.
Build quality? I think it is superb. The weight and the gauge of the metal on this piece still astounds me. It is like a battleship. 23 pds for the main unit. The painted finish is of the highest quality. The faceplate is so thick & the black anodizing on it is beautiful. The silk-screened lettering is perfect. Better than I see from some of the big names. In my opinion, the black faceplate is absolutely the way to go, and looks way better than the silver. There is a separate power supply in a metal case as well. The remote is very attractive & beautifully machined in silver. I read comments by people who think the Rogue too utilitarian looking, but I disagree. I think that people give this preamp a disservice by not seeing it in the flesh. Yes, the pushbuttons are a little large, & smaller ones would really push this unit into the gorgeous class. The RCA jacks are of superb quality, thick & substantial & with quality gold-plating on them. Certainly better than ARC's, for example. The silk-screening is very crisp & a quality job is done. (Cary is the worst example of silk screening) The internals are done very nicely with high quality parts, Raymond Mundorf capacitors, blah, blah, blah. Read the Stereophile review or see Rogue's website for the details.

A wonderful unit, & a bargain at the price. Despite Stereophile's review, I don't think this preamp is getting the attention it deserves. I agree with Chip Stern. For $2,395, I don't think anything can touch it.

Some of the recordings used in doing comparisons.

Dick Hyman - Swing (Ref. Rec.)
Fred Hirsch - Dancing in the Dark (Chesky Gold)
Sarah Vaughan - Mercury Collection, Vol. IV
Sarah Vaughan - various Roulette
Radka Toneff - Fairy Tales (Oden)
Frank Sinatra - Only the Lonely (Capitol)
Frank Sinatra - Reprise Collection
Harry Connick - 25
Ravel - Works for Orchestra (Analogue Productions)
Stravinsky - Rite of Spring, Firebird (London - Dorati)
Chesky Jazz Sampler Volume 1
Chesky - The Collection
Ella Fitzgerald - various on Verve

Associated gear
Audio Research VT-100 Mk II,
B&W 802 Matrix 3, w/Northcreek crossovers
Pioneer PD-65 as transport
Bel Canto DAC 2 converter
Audioquest Caldera, biwired
Acoustic Zen Matrix II interconnects
Acoustic Zen Tsunami PC

Similar products
ARC LS16
ARC LS7
SFL2
McIntosh C2000
kevziek
Keep in mind that the tubes chosen will make a significant difference. RCA's for warmer, Sylvania's for higher detail. I wouldn't recommend the EH tubes for the Bryston.
An update: the slight pop heard from the Mute button was eliminated in my more recent production unit by changing to a different spec resistor. This is such a minor issue anyway, and probably a majority of audiophiles would feel the same.
For what it's worth...My discussions with Mark & Mark at Rogue led me to believe that the front tubes in the 99 are one channel (can't remember which) and the rear are the other, with the signal gain tubes to the right (facing the unit) and therefore having the most impact on sound when tube rolling, and the Mu followers are to the left.

Incidently, Rogue et al is an excellent company to do business with and provide superior service should the need arise.
for the record in 2004 a Major upgrade was done to the 99
the new torroidal transformer is superb as well as other improvemnts to the power supply .The end result is the Bass is not only faster but tigher and the performance is rock steady even when you turn up the volume the sign of a well built preamp, also it has a seperate power supply
that givs you better isolation and controlwho else can do this for under $3k and BTW with tube rolling it is even better and I now think it is better than the Cary 98
which my freinds has and we have compared .p.s Rogue offers 2 even more substantial upgrades if you want to bring this to a reference level standard .for the money though even the $2595 model is a best buy !
I have been the happy owner of an R-99 for nearly four years. I love this amp as much as you can love a piece of machinery... But, I also really enjoy tube rolling. So, this little addition is really about finding the best tubes for the R-99...

During the time I have owned the R-99, I have tried many different new and vintage 6SN7 and VT-231 tube sets to achieve the best sound for my tastes. I began at the place most tube rollers begin: RCA, GE and Sylvania 6SN7 G, GTA and GTB tube sets. I then tried rarer and more esoteric types. All of them sounded good, but I ultimately found each type, whether I used them as front pairs or "followers", lacking for one reason or another. I later tried Sylvania and Ken Rad VT-231 tubes. While they sounded great in other amps I own, they fell short in the R-99.

Mind you, I was not unhappy while all this searching was going on. I was enjoying exploring the tube market and how each tube type changed the sound of my system. It was an education and amazing in that there were so many design variations, with resultant effects on the sound of the R-99, for the specification of the 6SN7 tube.

Finally, I happened upon World War Two vintage Sylvania 6SN7W short bottles. They sounded amazing in the R-99: liquid, detailed and smooth. They were also a little on the bright side, but I liked that. The ony problem was that they were highly microphonic. But, I learned to live with it: I loved the sound of the R-99 with these tubes so much, that some noise and feedback didn't bother me...

I used the Sylvania 6SN7W set, with a set of GE 6SN7GTA as "followers" for about two years, until one of the 6SN7W(s) began to make too much noise: popping and eventually just generating loud feedback. It was fun while it lasted, but I eventually tossed them. I searched for a while, but could not find a set of those tubes that behaved any better... I was at a loss as to where to go next.

Mark O'brien at Rogue gave me part of the answer: RCA red base (and CBS/Hytron) 5692(s). Paired with the Sylvania JAN CHS 6SN7WGT micanol brown base variety, from the late 1950's (which I happened upon somewhere along the line), they filled the void. In combination, these two types produce a sound from the R-99, that while not as bright and liquid as the earlier 6SN7W(s), is more detailed, controlled, and in its own way, musical. Importantly, though, they are stable: no microphonics. While I enjoyed the sound of the older Sylvania 6SN7W(s), I have never looked back...

I have tried the RCA red base and newer Sylvanias, each in turn, in the front position in the R-99. Currently, I have the Sylvanias in the lead. If you try this set-up, you may find that you like the 5692's up front. God bless... It's all about making the music sound best to your ears...

I really enjoy my system. It includes B&W 804s speakers, Rogue M-150 Monoblocks, a VPI Classic turntable with Benz Glider cartridge (love the cartridge, hate the company), Rogue Aries phono preamp with Mullard and Telefunken tubes, a Marantz Ki-Pearl SACD/CD player (#00019) and recently added Darwin Ascension interconnects (if you haven't heard these, call Darwin and get a pair or two: you will be VERY happy) and JPS Superconductor interconnects and speaker cables. I am very happy, but if a pair of Wilson Sashas or B&W 802D(s) fall out of a cargo jet and land on my house, who will complain?