Questions from a Tube Preamp newbie

@aberyclark

1. I leave my 12AU7 based line stage on 24/7 and the tubes just go on and on.

2. Yes, in my experience. After about a week they are where they will stay.

3. Don’t know as I have never had a tube power amp. With a total of 5 tubes in my system, I have found tube rolling to make a difference in sound quality.

4. Not a fan of JJ tubes in my experience. I use all Gold Lion 12AU7 tubes sourced from Cryoset. The tubes are cryogenically treated and seem, again to last forever. When you are ready to "roll" I would strongly encourage you to contact Ron Sheldon at Cryoset and give the Gold Lions a chance.  You can always talk to Ron and see what tubes his customers have had success with in a Rogue preamp like your's.

@stereo5  Good to hear that the NOS Mullards are working for you.  I sourced NOS Mullards from Upscale several years ago, and they sounded good but they just didn't last very long in my circuit.  No catastrophic  failures, just the tubes got very noisy.

@stereo5   Wow.  I'd have to check receipts but when I bought the CV 4003 about 15 or so years ago they were about $100.00 for a matched pair.  That was back in my early days with my tube line stage and just went with the advice I was given.  Perhaps I might have obtained better results with the Mullard 12AU7.

@stereo5   My previous post should have been stated more accurately.  The NOS Mullards I used were 4003s not 12AU7.  They were recommended by Upscale for my line stage.  Glad to hear you're having good luck with your NOS Mullards.  The 4003s I used yielded an amazingly smooth texture to the music.

@aberyclark   I only used one pair of JJs.  I abandoned them because of what I perceived to be a "hardness" to the sound.  The new production Gold Lions in my circuit yield an expansive soundscape, smooth textures and great dynamic swing.  This is referring to the Cryoset Gold Lions which are cryogenically treated.  I have no idea what the GL sound like without that treatment.  The JJs are inexpensive but when you have five figures in your system it seems foolhardy to cheap out on the tubes whose influence will be heard at all times.

@ejr1953   Did you get your Gold Lions from Cryoset?

@lous One current tube brand you may want to consider are Genalex Gold Lions sourced from Cryoset. I have yet to find any 12AU7s that work as well in my line stage as the GL’s. besides the fact that they have a neutral, dynamic, open sound, they last a l o n g time!

@buellrider97  I mentioned using Cryo'd Gold Lion 12AU7s from Cryoset.  I don't know if the cryogenic treatment has improved the sound of the stock tubes but I can attest to how long they remain quiet in circuit.  Ron Sheldon at Cryoset also tests the tubes carefully to supply you with matched pairs if needed.  

JUST A NOTE ABOUT CRYOSET...Ron Sheldon is very ill and has sold off his tubes and other gear.  A terrible shame.  I have had great performance from his cryo'd tubes.  Unfortunately bad things do happen to good people.😔