2. amps-preamps
  3. 1387471762

PRIMA LUNA owners, what power tube are you using?

To all Prima Luna owners, specifically those with a DiaLogue One integrated amp (although owners of the new Premium amps and the ProLogue series are more than welcome to chime in with opinions and feedback), which power tube are you currently using? Which others have you tried in the same amp, and what made you prefer the ones you ended up going with? And, of course, please specify what speakers you are using the amp with.

I own a DiaLogue One myself. Happy owner for close to 4 years now. It comes standard with EL-34's, and it's, in fact, designed for that specific tube. But Prima Luna amps are a tube-roller's delight, and the manufacturers encourage trying other types.

Personally, and after experimenting with the Gold Lion KT-88's and Tung Sol KT-120's, I ended up going full circle and back to where I started: the stock EL-34 tubes. These are labeled as "Prima Luna", but are actually made by Shuguang in China and, supposedly, only the best rated ones end up being used for the Prima Luna amps.

My system consist of the DiaLogue One, Sonus Faber Toy Towers, and Oppo 95 for CD's, SACD's and digital files (mostly hi-res and FLAC files sourced from an external drive), Pro-Ject RPM 5.1 SE with a Dynavector 10X5 for analog, and Nordost cables all around (Brahma PC, Heimdall and Red Dawn LS interconnects, etc).

My journey could basically be described like this: I started with EL-34's, loved the sweetness, transparency and midrange magic but needed a little more grip on the low-end (and also detected a hint of harshness in the upper highs from time to time), so I switched to the re-issued Gold Lion KT-88's. The Prima Luna auto-bias feature took care of the rest. I LOVED that combination (and loved the way the Gold Lions LOOK, as inconsequential as that sounds), but reliability was an issue. One exploded while in use, and the rest would loose their sparkle and life in less than a year, with moderate to low use on the amp. At $200+ per quad for tubes that don't even last a year, things get expensive really quickly, so I needed an alternative.

I then tried the KT-120's that everybody was raving about and that were actually cheaper than the Gold Lions. Originally, they were not my cup of tea. Too aggressive and bright on the one hand, but not that much different than the Gold Lions when it came to added bass grip and control. I actually gave them a second chance, burned them in for at least 200 extra hours and they definitely got better (less harsh on the top, rounder in the mids, but, again, with no extra "grip" gained on the bottom). Still, the magic was just not there and my amp was never designed with that tube in mind anyway, so why even bother?

I then went back to the stock EL-34's that I still had sitting in the closet. These were not as "sweet" and "magical" as I originally remembered them, ironically, offering bass aplenty (albeit looser, slightly sloppier bass, a quality that for some reason I tend to like on most material since it seems to allow the music to feel more tangible, less sterile and artificial), and an incredibly more open, extended and detailed soundstage, which definitely got "wider" and more STABLE when compared to the KT-120's. With the emphasis being on the mids, there's a lot of details to be gained that were perhaps a little obscured by the more linear characteristics of the KT-88's and KT-120's. Notes in the upper-lows are now considerably more clear and I'm simply hearing a ton more music in the bass and low end. Yes, the KT-120's were sturdier and allowed my Sonus Faber Toy Towers to go a little lower, no question, but at the expense of detail and finesse, I believe. This translates into a significantly more "crystalline" presentation, with the well-known musicality and ripeness of the EL-34 in place, and one that I am finding myself preferring. It all works wonders with jazz and classical, particularly with strings, but rock albums actually sound more vibrant as well. Certain passages tend to break up a little bit, but oddly enough this only happens with very few instances of highly distorted guitars and/or very, very complex passages on extreme metal albums (a genre I also love). Overall, though, I think the EL-34's are back and staying, at least for now. Next experiment: the Gold Lion KT-77's. Anybody have any experience with them?

Would love to hear about your own experiences.
beyondarkness
dazzlingmd
71 posts
 
Rekindling an older thread as I recently had a lot of fun with a good ol' fashioned tube shootout with my Primaulna Dialogue Premium (which I'm just running as a power amp through the Home Theather bypass right now).

I had a lengthy shootout, with many different songs and types of music, with the stock EL-34s, a set of KT-120s, an NOS set of RSD (RFT) "Siemens" EL-34s, and a set of PSVane 6CA7-T tubes. I burned in the KT-120 and PSVanes for about 60 hours each before doing any serious listening.

Honestly, to my ears, it was easy to narrow it down to the RFT Siemens and PSVanes, and from there it was difficult to choose between them.

The stock tubes don't sound bad at all, but head to head with the other tubes, the bass was a little loose and flabby, and the midrange a little thinner. I also did not love the sound of the KT-120s. I know I'm in the minority on that, and the bass was nice and tight, but I thought there was a little something missing in the midrange and slightly tinny on the high end, in direct comparison to the NOS and PSVANE tubes.

I did a run-off shootout between the NOS RFTs and the PSVANES, and went back and forth about 20 times as to which ones I preferred. I ended up going with the RFT Siemens. Although the differences were very subtle, at the top end the RFTs were ever-so-slightly more forgiving of my less-then-stellar recordings. But I could have lived happily with either of those forever.

Overall it was a fun experiment and now my system is sounding even better! By the way, quads of the NOS RFT/RSDs can be found on ebay for about $160, so they are one of the better values for NOS EL-34s in my opinion, but you do need to look closely at the pictures and look at the feedback and make sure they're the real thing.
mikirob
955 posts
 
Dazzlingmd,
I recently did the same shootouts between the RFT Siemens and Black Treasure 6CA7s. In the Dialogue I like the RFTs best so far. In my Coincident Dynamo 34se I prefer the Black Treasure 6CA7 even though they are still breaking in. I have used Gold Lion KT77s as well, but they rank lower on the list to my ears.
dazzlingmd
71 posts
 
Very interesting, Mikirob. What differences did you find between the Black Treasures and the RFT Siemens? I felt like I was splitting hairs a bit to hear much of a difference at all, as they both sounded great, but as I noted above, found a small difference in the high end. I'm curious what areas you found to be different as well.
mikirob
955 posts
 
Dazzlingmd,
In the Primaluna Dialogue 1, like you, I thought it was splitting hairs. Ultimately I believed the RFT Siemens ever so slightly had a fatter tone and was smoother on top. The Black Treasures had better bass, more extended on top, very slight etch on some recordings, but I expect this to smooth out over time as these tubes break in. The mids on both were superb.

On my Coincident Dynamo 34se (8 watt DHT) it was no contest. The BlackTreasure 6CA7s were definitely superior in every parameter. The Coincident has a 60s Mullard 5ar4, Jan Sylvania 6slt. The Primaluna has NOS Bugle Boy 12au7s and NOS 5761s. They affected the sound the most over stock tubes and other brands.

I really like the Reflector NOS 6n3ce tube (6L6) in the Primaluna as well.
dazzlingmd
71 posts
 
Thanks. Very interesting, and also good to know that I wasn't completely crazy. At least not with respect to this particular shootout.

I'd like to try out a Coincident amp in my system someday. I can seem to find nothing but universal praise for them. Right now things are sounding quite good, though, and someday I'll have to figure out how to just relax and enjoy the music for a while!
More to discover