DNA amps with the exception of Starlett are optimized for 5U4G, other options have trade offs with the voltage and other technical stuff I am unable to relay.
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2 out of 3 of the same pieces are not bad for a comparison here. The most important question in this comparison; Were you listening in your garden, or indoors? 
True. 2A3 and 5U4G are directly heated, while 5AR4 is not.
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It’s my understanding in the stratus, you want to be using directly heated rectifiers.
Donald is usually pretty responsive to questions about this stuff.
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That is my understanding also based on my conversations with him. I agree - he is responsive.
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Welp. I gave a call to Andy at VTS, and he had some interesting thoughts on both 5U4G and 2A3 tubes.
In terms of 5U4G, he was of the opinion that interactions of the rectifier with the amp can vary widely and are hard to predict. He also doesn’t seem to be particularly enamored with the “holy grail” types (GEC/Osram U52/5U4G, and the like), and recommended RCA. I take everyone’s advice with a grain of salt, but the RCA rectifiers do seem to have pretty consistently solid praise around the audiophile forumsphere, so I went ahead and grabbed one of those. As a side note, Andy also has a WE 422A, if anyone is looking for one.
In terms of 2A3, he basically said that the Chinese (PSVane / Linlai) tubes can sound really good, but that they tend to be relatively short-lived. Then, he echoed @perogie’s mention of QC issues for KR. He said that the tubes are great when you get good ones, but you often don’t, and that KR is a pain to deal with in terms of warranty and replacements. Now, I’m sure both of those are a bit skewed, as the customers who call him will be the exact set that had issues and need replacements, but I’m sure there’s some truth there as well. In any case, he recommended either vintage RCA’s or Sylvanias that he had on hand, saying that the Sylvanias would be cleaner and airier with more detail, and RCA is a bit weightier and creamier. Those who know my sonic preferences will not be shocked that I asked for Sylvania. He had two different pairs, and after explaining a bunch of stuff about the tube construction I don’t understand, I asked him which was better, and took that one. 
So, long story short, I should have an RCA 5U4G and fancy Sylvania 2A3 tubes on the way to me this week!
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Ive never spoken to Andy but his opinions as related to me tend to centre around the “value” proposition, which is actually a nice change; however, if he had a holy grail I wanted I wouldnt let him talk me out of it. The RCA is a good strong value buy in 5u4g’s.
Having said that I do think holy grail tubes are treated as such for a reason - talking the true holy grail, not the Headfi FOTM tubes. But we might only be hearing multiple small improvements best heard on high resolution systems.
I would have gone Sylvania 2a3s too if I was in your position.
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Right. I get the same impression as well.
With you on this one, too. Given that this is only a demo, and given that the Philips Miniwatt GZ34 I have on hand qualifies as “holy grail” (though, not optimal for this amp), and does sound quite good, I wasn’t in a rush to spend $500 on a rectifier. Of course, if I do place an order for a Stellaris, I’ll be much more open to investing in a truly top-end 5U4G.
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I love talking to Andy because it feels more like getting advice from an expert, rather than someone trying to sell something to me.
He steered me away from holy grail and towards good value (examples of his advice were “Why would you spend more on a 5U4G than an RCA, when they invented it!” or “Why pay more money for a 5AR4 with an Amperex label when you can have exactly the same tube with a Valvo label at a discount!”).
And he has a really good return policy. I can’t remember if he offered me a credit card refund when I returned my RCA 5U4G but I told him I’d rather have store credit because I wanted to purchase from him again.
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Oh that sounds promising. I replaced the stock PSVANE 2a3s for EMLs and enjoying the sound much more.
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Has anyone listened to this and also the WA33 elite? Would love to read some comparisons.
Indoors. Too much street noise in one place, too much wind noise in the other…
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I have a standard WA33 and a Stratus.
They are just very different amps, The Stratus is a SET amp and sounds like one, it doesn’t have excessive midrange bloom, but it certainly has some. I also wish for some headphones the low impedance out on the Stratus were a hair lower, I work around it by using SE out in low gain mode where the impedance drops to 3 Ohms, which works well for the D8KP.
The Woo is a push pull design, so it’s missing the SET sound, but it has better resolution, stages better, sounds cleaner, faster, better overall impact/macro dynamics and works much better with some harder to drive planars, I prefer it’s dryer sound on a lot of headphones, but YMMV.
It’s also more than 2x the price so…
Both ship with similar quality tubes from the manufacturer and both desperately need a rectifier upgrade at a minimum.
Can’t compare the EE to the Stellaris, because I don’t have either.
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There’s likely to be a sonic difference based on the power output alone: 10 watts @ 32 ohms vs 1.8 watts @ 50 ohms.
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The Woo WA33 had been on my end-game list in addition to a Stellaris, but had recently fallen off a bit. I just got the sense almost everyone pairs that amp with hard-to-drive planars. What headphones are you using with your WA33? I feel like it’s hard to find tube amps that match well w/ Utopias due to their sensitivity, and the Stratus has the lowest noise floor of those I’ve tried (though, recent tube upgrades got my Woo WA5 down to no perceptible hum as well). Mostly wondering if I should still be considering that amp.
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Predominantly I use Susvara’s with the Woo, they’re the reason I bought it I wanted a workable tube option for them in addition to the SS I already had.
While I think the Woo would be fine with the Utopias sound signature wise, I think you run into the same issue I do on easier to drive headphones like the D8KPro and ZMF’s, there just isn’t enough motion on the volume control even on Low Gain.
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@andris Really interested in what you think of your tubes when you get them.
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As a lot of folks on this thread suggested, rectifier rolling made a more meaningful difference than swapping out the power tubes. The stock rectifier tube is super quiet, but also noticeably bloaty. Switching in the Philips Miniwatt metal base GZ34 cleaned that right up, but it wasn’t perfectly quiet, though I only got audible hum when turning the amp almost all the way up (with no music). The NOS RCA 5U4G wasn’t quite as tight and controlled as the GZ34, but better than the stock tube, and super quiet. Neither the GZ34 or RCA 5U4G had audible hum at listening levels, but the lower noise floor of the 5U4G was obvious nonetheless. That’s all to say, I don’t think my search for a rectifier would be done with the RCA 5U4G, but it’s an acceptable starting point.
The Sylvania 2A3 spring tops were indeed clearer and airier than the stock PSVane 2A3 tubes, but the difference wasn’t so stark as to transform the amp. I’m certainly glad I got to try them out, and I’ll be keeping them around. I certainly don’t feel the need to keep searching for a 2A3.
Now to the crux of the matter. To Stellaris, or not to Stellaris; that is the question.
After two weeks with the Stratus, I feel comfortable in feeling that it’s the sound signature I prefer - even over my beloved Woo WA5. As such, I’m leaning toward taking the plunge and ordering a Stellaris, lest something completely unexpected change my mind in the next few days. I had a lovely chat with Donald today to get all of the specifics, and will be spending my next few days trying to figure out if I should order the “stock” Stellaris or Stellaris special.
So - and I know this is a long shot - has anyone here put their ears on a Stellaris special? Or even both? Any and all input is greatly appreciated. 
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I have not.
I believe the Stellaris Special comes with speaker outputs, which may be relevant to the determination.
By chance did you compare the different outputs and TRS gain/impedance on the Stratus?
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@andris … thanks for the update. I found swapping out the stock Psvane for EML 2a3s in my Stratus made a significant difference to my enjoyment. Now you have me thinking I should roll the rectifier, too. Sorry for not re-combing the thread but what’s your best source for the RCA 5U4G?
I would certainly go maximum Stellaris if a) I had the money and b) headphones were my primary way to listen to music. I’m finding that my headphone music listening has decreased as my deep dive into vinyl has become the major focus of my listening … I now need a good tubed phono pre-amp in order to listen to LPs on the Stratus (my digital integrated only outputs to speakers, and a headphone jack which is great for digitized sound). However, when I want to sail the sonic sea for an hour, I fire up the DNA and set off into blissful adventure.
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