Does anyone know at what plate voltage and grid voltage the Lyr3 runs the tube? I was curious about that but couldn't find anything in Schiit's specs or owner's manual.

Ah, got you. It hasn't arrived yet, but I'll post my impressions once I have it here.

So is this a re-branded Sylvania tube? The print says RCA but from reading in this thread I've learned that re-branding tubes as manufacturer A when in fact manufacturer B had made them was not uncommon back then?

Does anyone know a bit more about this tube? I got it quite cheap from eBay couple of years ago and I've been very happy with it in my Schiit Lyr3 ever since :) According to the seller's information it's a US made tube (obviously) from the 50s or 60s made to German military...

Has anyone compared or owned an original T1 and a T1 SE? Are there audible differences? I think about upgrading to the T1 SE... :)

http://www.ebay.de/itm/6N23P-russ-Zweifachtriode-in-Spanngitterbauweise-Made-in-UdSSR-/251576239291?pt=Röhren&hash=item3a931cc4bb   Here's one. With shipping to the US 10$ (7,50€). ;) In used condition but the guy says tested 100%/95%. A bit funny but this offer isn't listed on ebay.com even...

  Yeah I actually thought so too, because when you search the thread for 'distortion' the only thing you'll find are posts concerning ECC85 tubes  But no problem, I just didn't have much time for the forum lately that's why I didn't comment on that. Can't wait to hear all these tubes... 

  Yes I've read about that. But I just follow the strategy to buy a couple of these tubes very cheaply and then I'll just try them. Maybe I'm lucky and get a good one, maybe not. And then I'll just sell them again and end up paying a few € for postage.

  I did some extensive tube buying on eBay these weeks and I even got a 'rocket logo' for 5€ (50% of it shipping). It's funny though, E88CC - especially Valvo and Telefunken - will fetch much higher prices than, say, PCC88 (which are exchangeable for the T1 and I guess most other applications...

True but the gain also heavily depends on your music files and how they are mastered. Just think of the extreme contrast between digitally released EDM compared to high quality recordings of classical (piano) music.

http://www.upscaleaudio.com/tube-faq/   According to the last paragraph, external vibrations could be picked up by the tube and influence the sound. And maybe if you place the T1 right on top of your subwoofer the tube could be shaken as badly as if you would tap on it. Maybe I'm not an expert...

  Mh I must say I find that hard to believe. Usually the driver or playback software will create a buffer of some sort to ensure the DAC will be fed continuously with data. I had another DAC with ASIO drivers and constantly had issues with it because it did not feed the DAC well. But I think...

Thanks to all of you guys, this thread is really informative when one is looking for tubes.    Once I have all my tubes (some of which are not fully reviewed here), I'll also post some tube impressions.