Random late night post as Im tired of watching anime for today: I am consistently finding about 30-45 minute run time before things settle in, whether thats amp related or my own brain it seems to be what Im finding, I would wager psychoacoustics. DAC is always on.
Its not huge, just things sound a bit more cohesive, instruments a touch sweeter. Psychoacoustics. As you were…
I believe it - brain/ear warmup. Or a notion of time needed to reach that zen state in order to be worthy to receive the music.
When Donald dropped off the amp, he mentioned where he lives and how it’s centrally located and an easy drive to LA’s live music venues. With LA traffic, that’s significant. It also informs me that his ear knows what live music is supposed to sound like, and I believe that comes through in what I hear. This is probably similar to Zach’s background of playing guitar/banjo and building guitars. It’s not a prerequisite, but definitely a favorable influence that underlies the quality/character of their products.
I’ve got an idiosyncratic tube in my ZDT Jr. that hums if I move my hand towards it - as though it’s telling me to back off, pal, if I get too close. The cool thing about this? I can now easily add a one-note, bass theremin to any music I’m listening to.
Brilliant 
20 char
5U4G - pointless quick impression. (NOS, balanced, RCA made black plate)
Definitely more punch over stock rectifier, increased bass presence but still sounds controlled, staging feels improved in depth. Treble energy a bit increased. Essentially I agree with @tommytakis impressions. I dont detect any clarity loss. Sounds a bit less rounded off.
The only con is I feel there is some midrange recession, so essentially a U shaped sig.
Overall this is a tube roll Im pleasantly surprised by so far.
Weeeeeee glad you like it!
Thanks for confirming that I’m not totally deaf 
Enjoy!
I like it so much that I let my friend who has the Sonett 2 borrow the extra RCA I have.
I may have found a nice combo but Im not gonna comment further until I got more ear time and tried some other tubes.
I still got to find some power tube subs I like.
Got 3 new preamps today as well and some more coming probably Monday (mainly power tubes and the 6N6P).
Should be an interesting weekend seeing what I got. Hard for me to stop listening but I got some stuff to do, grumble.
Donald mentioned that he chose 2A3 partly because it is lifelike and pure sounding telling it as it is as if you’re in the room, whereas 300B can try to impress and put on a show that is better than real life, and 45 can be even cleaner and leaner than the 2A3, and the 211 and 845 can lack some presence and you’re seated further back in the music hall. I believe this 2A3ness DNA shows up in the Starlett.
When paired with my Modi Multibit and HD650s which are more chill and relaxed, that can be too much of a thing (anti 300B above) depending on mood and genre. This might be resolved with a quicker driver such as the Eikon. While the music remains enjoyable, my DAC seems to be revealed as a weak link in this chain.
So the 5U4g is good enough that Im gonna get a back up, maybe even look for a JAN just to see if that designation means anything sonically. A few of my preamps match up fairly well and take care of the midrange/low treble recession I picked up initially so Im happy there.
Will still get a NOS Mullard 5AR4 because I will always wonder if I dont, easy to sell if Im not impressed.
So my initial thoughts about tube rolling in the Starlett is that you probably dont have to do it to get something really good out of it. However, if you are interested in it and are willing to spend the time and money on it (not much comparative to other amps) then exploring it is fair game. It is very much about how everything plays with each other and you may find magic. Not saying this to induce the “tube nervosa” just saying it to let people know you are not wrong to try it out. There appears to sometimes be a slight placed against audiophile folk who like to swap tubes, if you’re having fun with it than go with it within reason.
I rolled because why the hell not and Im happy I did as it was a good learning experience and simply fun to see what tubes can do. You may also come across something completely magical, which I may just have, that makes it all worth it. Or just stick with stock as thats good too.
@perogie I already picked up an EML 2A3 ungrade pair for the Stratus that I ordered (4 mos away hopefully). I’ve read that Mullard 5U4G is a good one to upgrade, but was going to ask Donald’s rec. Will follow your impressions closely. It’a been fun to read this thread.
Good for you! I had a couple different preamp tubes waiting for the Starlett to arrive.
New production 2A3s seem to be pretty good for the most part, the EML and Psvane Acmes seem to be favourites. I have come across a few threads online stating that the Shuguang 2A3, which I think is the stock tube for the Stratus, is apparently a very good value. Value is a personal thing so hard to say what that means.
Ive seen the pricing on some of those Mullard 5u4g… I’ll stick with the RCAs.
Ive been really impressed with the RCA 5u4g, it has provided that last little bit of low end I was hoping for without over doing it. Maybe not quite as tight as the stock 5ar4 but its only mildly less controlled. I’ll see what burning in does with them. The staging and dynamics are improved. Really starting to notice the improvement in macrodynamics, @tommytakis would be proud of me. Staging improvement is noticed mostly as an expansion in the depth and height, not much wider than what I had before.
This is where my having different tubes made a difference. If I just had the stock tubes and rolled in the 5u4g I wouldnt have kept it in due to the U shape it created in the FR to my ears, but rotating preamps raised up that middle and now makes it a nice addition to the tube family.
Outside of power tube backups Im pretty happy with what I have tube wise, but will keep looking here and there. Its surprisingly been the tubes I bought as a cheap what the heck kind of purchase that have helped me most in getting to where I think the Starlett is shining near as bright as it can.
Hopefully the thread will keep being fun and keep you somewhat entertained until the Stratus arrives.
Good info, thanks!
I may have missed it above, but how much/how easy are the RCAs to come by?
Yes – looking forward, to the Stratus, and further observations!
It wasnt hard for me to find a decently priced one. However, I dont think they are that readily available; they dont seem to have a widespread presence amongst a lot vendors. Ebay has some but that can be somewhat dicey unless its a well historied seller.
If I remember, basic RCAs (RCA made but might not be RCA labelled) seem to run anywhere from $10 - 40 depending upon vendor, JAN type RCA seem to run 100 - 200. There is some in between pricing but I think you are paying more for aesthetics - RCA label in good condition, tube shape, with a lot of it.
Psvane also makes a new production 5u4g for $60.
The Starlett tubes can be had real cheap (current favourite complement is probably $60 total) and I am fortunate enough to have enough discretionary income to play around with so I can try out a few things just to see. I understand not everyone can do that so my playing around may save people some money down the road.
$Psvane for 60 would be OK. I think those Mullards are like 400 and up if you can find them. The EMLs were not cheap but I got a good price from someone on the forum.
Im curious about the Psvane simply due to them being new production and acceptable pricing. I want to know if I can get something decent if the old stock dries up.
The Psvane Acme 2A3s are near 600 a pair and the EML are more than that I think, take any deal you can.
500 pair … For EML.
Retail or the deal you got? Seen them retail for over 700.
I’m curious about those but I’m not a bass head, or at least I’ve always had the impression they were bass heavy.
