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?
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?