Which 6sn7 tubes for Rogue Magnum 99

I currently have four EH 6SN7 tubes in the linestage. What tubes are good for this preamp? I thought that only 2 of the 4 tubes really make a difference, but not sure on which ones, front 2 or rear 2. Not looking to spend a fortune on tube rolling.
call Mark OBrien at Rogue he told me which tubes were the most important when I owned the 99 but I forget which ones myself...

I think the 2 on the left make more difference, the 2 on the right are mu followers, I think, but check with Mark he is a very easy fellow to talk to...
If you want to try NOS,go for a Sylvania JAN WGTA brown base.I paid $60.00 for a pair about a year ago.They are rising in price every day as all NOS tubes are,so grab some now if you want to try them.The difference in sound is worth the money in my opinion.Good luck.
I agree .. .call Mark at Rogue first. Then, perhaps, call Dennis Had at Cary Audio in NC. He knows a ton about that tube and uses it so often in his gear. He is a "23mA kind of guy" in his own words in that he likes that as the bias current value in his 6SN7's in many cases. It is not just the brand or age or production run or specific design of the tube, but also the current draw it has that also largely impacts the sound. More current draw typically means more rich, full bodied, and warm sound with greater coloration to those aspects or traits. It can be like listening to a tenor sax versus an alto sax. Lower current draw typically means thinner, more incisive, and less coloration. A 6SN7 can be quite coloring and warming on the sound as well as fleshing it out thickly so. Try several of different brands and current values unless you already know your preference for sound types in general as described above.
I'll assume you're interested in NOS tubes (and you should be if you're not!).

I don't know which 2 of the 4 matter most, so when I owned the 99 I swapped sets of 4 that I bought on eBay from reputable sellers.

In the realm of reasonably priced tubes, RCA black plates will tend to add some warmth and Sylvania black plates will add some detail and emphasize higher frequencies.

With one set of speakers I preferred the RCAs, with another the Sylvanias.

The 99 responds well to tube rolling and there are lots of options for 6SN7s. Good luck.
Sylvania's are best IMO. Also I use two of one brand and two of another brand this works really well.

As you look at the front of the 99Magnum preamp, the two tube sockets on the right are the amplification tubes. They are the most important for having low microphonic tubes. They are also the two that will have the most effect on the sound. The two tubes on the left are the mu-follower, or driver, tubes.

Steidlguitars was correct when he said that the choice of tubes will be system dependent.

I tried RCA in the amp side, Sylvania in the driver side: a little too much sibilance in the system for me.

I tried Sylvania in the amp side, RCA in the driver side: way, way, way too much sibilance in the system for me.

I ended up with all RCA tubes.

Sold the Sylvania tubes to a guy who comes into our local shop and who has a darker sounding system - he loved them... and subsequently bought two more for the driver side... still loves them in his system.
Mark told me if you want more transparency or pop which is what I wanted he said with Sylvania GTB's. He was right and I bought a pair relatively cheap and love them. They were NOS tall boys and talking about dynamics. Lusher sounding tubes would be RCA. The GT and GTA's of the Sylvania family do have a little more sibilance as mentioned above but are smooth and detailed.
The NOS Sylvania GTA and GTB tubes that I had in my system were indeed smooth and detailed as Samzx12 described and are absolutely a great tube. I think the sibilance part is going to be system (and preference) dependent. In my system, it was too much for me, but as I mentioned above, another guy in the shop loved them as they transmitted more air and detail through his system than ever before.
Anyone tried Sophia's and how do they compare to Sylvnania Bad Boys?

Here's a list of what are considered the best of the 6SN7 family, and what you can expect, with regards their presentation: (http://www.tubeseller.com/ratings.php)