Sweetest sounding 12AU7?

I have a Rogue 66 Magnum that came with Radiotechnique tubes.I have had these before in my old 99 phonostage along with some Telefunken 12AX7's
The old 99 phonostage sounded very good with this combination.
In the 66 linestage the R.T.'s sound somewhat bright.Im not sure how many hours are on them but I know they are fairly new.
Im wondering what a good 12AU7 would be for the 66.
I also have a pair of Sylvania's that came with the 66 but havent listened to them.I would guess they arent that great.
Any leads for a sweet and warm 12AU7?
Anyone have experience with Tungsram?
I liked the sound of Amperex Holland labelled "Heirlein" or something like that. Tamed some bright or forward upper mid range problems as voltage stage in a Llano Trinity hybrid amp.
I just ordered replacement tubes from Rogue Audio for my 66 Magnum version. Rogue highly recommended National's for the 66 line stage.
Just pulled them out. Generic tube box is labelled Heerlen but tube itself says Dumont Made in Holland. It presumably is an Amperex.
I actually think that the Amperex Bugle Boy ( Holland or France ) are some of the best NOS tubes available. Many like Mullards and Telefunkens,but for me the Amperex Bugle boys are the best of the best....

Sweet/warm 12au7 types in my preamp and as an input tube in one of my power amps are:

RCA/Sylvania/GE USA tubes from the 50's/60's (THIS DOES NOT include RCA "clear top side getter" tubes, which I do not consider to be sweet/warm). I also use 5814a's, same brands/vintages as above.

Never used a Euro 12au7 type that I consider sweet/warm with the exception of a handfull of Mullard 12au7 types (have most common Euro Telefunken/Amperex/Siemens versions).

However, you might go broke trying to find a decent warm/sweet Mullard pair, IMO, as their sound/quality for this particular tube type is all over the map (different versions/vintages/productions).

The good news is that the USA versions I mention are common/cheap.

If your Sylvania's have yellow print, then they might be just the ticket (later versions have green print).

Not knocking the Euro types (just don't find them warm) as I do use them when running a Grado phono cartridge as an offset.

Whatever you do don't waste your money on the mid 80's Mullard military 12au7 versions which have flooded the market (the leanest/meanest 12au7 type that I've experienced).
Dekay- I have the latest Sylvania's (green print)
These came w/the 66 Mag. and the original owner didnt use them as he went with R.T.'s
These Sylvania's are supposed to be the upgraded tube for the magnum vs the non-mag 66.
Although I like Rogue Products,I dont like the tubes they offer.
Mark O. gave me a quad of the Russian NOS 6SN7's he was considering adding to the 99 magnum and wanted my opinion.I felt they were no better,no worse than the NOS Penta Labs tubes that I paid more for when I bought my 99.
He went with the Russians anyway.
The reason I mentioned that I doubted the Sylvania's would not sound too hot is because they go so cheap.Maybe Im a simpleton for thinking that way.
I will give the 'green' Sylvania's a listen this week.
Can you describe the difference sonically between the older and the newer Sylvania's and what the price difference is?
Thanks Dekay,I always like it when you respond to my threads.Happy New Year!
I've been using those late 50's RCA "non clear tops" that A'goner Terribleted is selling for $10. apiece with "Hammond" label used. Much better,sweeter than current JJ 12au7.
Hi David:

I've never tried the later Sylvania's (Green). I have used Green 6922/6dj8's which were pretty good though (they were specialy screened/selected).

You might ask Rogue about using 5814, 6189 and possibly 5963 tubes. The 5963 tolerates less plate voltage than a 12au7, so it's not a direct sub in all circuits.

I'm also curious about Tungstram Ecc82's, but stopped buying tubes quite some time ago. They used to be listed @ ATSI Tube.

Maybe try a "Rogue 12au7" search @ AA? I prefer to research tubes as they are used in my paricular gear.
I have some good bids on eBay on matched pairs of 12AU7 Tungsram and the yellow label Sylvania's.
With my Radiotechniques and green label Sylvania's I'll be rolling in tubes for quite some time!
I'll post at a later date my findings.
Thanks Dekay and all others who responded.
I've tried many different tubes and have settled on two Tungsram 12au7's and one Tungsram 12ax7 (welded). Very sweet, full, accurate sound, with great soundstage and highly accurate timbre. BUT of course the sound is somewhat system-dependent!
I've tried many different tubes and have settled on two Tungsram 12au7's and one Tungsram 12ax7 (welded). Very sweet, full, accurate sound, with great soundstage and highly accurate timbre. BUT of course the sound is somewhat system-dependent!
When you're talking "sweet and warm" I would suggest a pair of British Mullard 12au7's, NOS. Approx. vintage 1960-1965. Talk to Andy Bauman of Vintage Tube Services. I talked to him at length about this, and these are what he recommended. I have had several pairs of these tubes and they seemed pretty consistent in sound quality.
What do you folks think about the Amperex Bugle Boy Vs Genelex Gold Lion re-issue?