Tube rolling Audio Note DACs

I have an Audio Note 2.1x balanced DAC. One of the output tubes recently went bad (they were stock Philips) so i replaced them all with NOS in a bit of tube rolling fun. However, I could swear the new output tubes -- 7308/E188CC Siemens 1969 branded Westinghouse -- have a recessed midrange, but I can't be sure about this as these tubes also have better bass and high-end output than the stock tubes. They may just be better balanced.

Any other output tubes to try on the AN DAC?

Amperex PQ 7308 gold pins (or JAN) or mullard gold pins for richness, gold pin telefunkens for soundstage and balance (recommended in the audio note manuals by peter for what its worth, so close to how he envisioned voicing the dac - see my fav below);

now warming up some Siemens GEB E188CCs, so can't comment on signature yet. Personal fav is Tele CCa so far (does so many things right, but especially top-to-bottom range and soundstaging), but just love several of the amperex tubes. Valvos (original) have a full rich midrange too. If you want, let me know by email and I can look through my notes and my tubes to give other suggestions or more details (plus can point you to some great audiogoners whom I have found to be well-informed and trustworthy sources for some of the more interesting small tubes - oddly, different people for different specific tubes!)... Curious to know the rest of the setup so I might comment on particular synergy too.

Best of luck,
clarification - I saw your system list (neat system by the way - should be a lot of fun to listen to!), but wondered what the other tube complement was...
sorry for the fragmented posts - not my best day!

Incidentally, changing the rectifier helps a lot too. Confirm the type and I can see if I have any spares that you like (gratis since most of those I can never use and feel guilty for hoarding when you could use it)...
Jwaugh, Thanks. The rectifier tube I added was a Tungsol 6X5GT 1957. This is supposed to be a pretty popular tube with AN DAC users. And frankly yes, my system is fun to listen too. I'm glad to be at the point where I am. Some people dis Mcintosh, but I've tried many other brands and in the end you know what i like.
There was no mention in the manual about tube rolling or recs for such.
I put a pair of new JJ/Tesla E88CC into my 3.1x Balanced, and they did a very nice job - better extension and even more of that wonderful midrange clarity. A pair of NOS Brimars didn't work out as well. I left the rectifier alone.
I have a pair of Siemens CCa in my AN DAC 1,1 sig and they sounds great.
Interesting! I don't have my manual any more since I sold the 2.1x balanced, but thought it interesting that it was in there. Perhaps a different rev. of the manual. Mine was from Fall '03, so perhaps he added the section. Of not, I do still have my old dac 2.1x signature and its manual. The exact quote comes under the section titled "Experimenting with Different Valves" just prior to Warranty and Servicing" and it reads: "The best I have found is the Telefunken E88CC 01 gold pin, expensive, but worth every penny." As I mentioned, the CCa is close but preferable in my system... but it is always interesting to hear equipment the way the designer voiced it.

The TS is a nice rectifier. It is one of my favs for 6x5gt, but I have a slight preference for Mullard and Bendix. At that level, it is just a matter of taste, though.

Still recommend Tele CCas for detail and extension and the Amperex 7308 (JAN or PQs) for richness. Can't compare the two yet since my older PQs have not yet arrived...
I've tried these 3 tubes:

Telefunken CCa gold pin
Westinghouse 7308 E188CC gold pin

The Telefunken is my favorite. It is clearly better than the JJs with an
even presentation over the frequency spectrum. Very nice midrange, but
I think it's a bit rolled of at the top but i can live with that.

The JJ is fine for a tube that is 1/10th the price of the NOS tubes. Clean
from top to bottom, just not as clear as the NOS tubes.

The Westinghouse had great bass and nice, clean highs, but a recessed
midrange that i could not get over.

Naturally the Telefunkens are the most expensive. This was an
expensive exercise for me, but definitely a good learning experience.
Each tube is different and perhaps none is perfect. This is frustrating in
a way because once you buy the component to get the most out of it you
have to fine tune it with tube choices (but this is of course an advantage
too). Part of me wants to go find a nice SS DAC so i don't have to worry
about tube choices, but the Audio Note DAC is SO DANG GOOD I can't
do that! Everytime I take the cover off the AN to change tubes I'm very
impressed with the clean elegance inside, and the screws are top notch
too. A real winner.
I recently put a pair of NOS Siemens into the 3.1x Bal when one of the JJ's went down. The Siemens sound more musical than the JJ without losing any clarity. Interestingly, in my preamp the Siemens sounded thick in the bass and rolled off on top, and I much preferred a pair of Amperex. The Siemens sound much better in the DAC.