Audio Research or Conrad Johnson Tube Pre-Amp???


I am looking at the purchase of an Audio Research SP-9 or SP-14 or Conrad Johnson PV-9a, PV-10, PV-11 or PV-12 pre-amplifier. It's very difficult since I've not been able to hear every one of these pre-amps. However, I do want a tube pre-amp to mate with my Threshold S/300 and Mirage
OM-9 speakers. Later I plan to purchase Magnapan 1.6 speakers. I will also be using an Elite Rock Turntable with Excalibur tone arm. I will also be using two professional tape decks for recording and playback.

I really need assistance regarding the following:

1. Which pre-amp will work well.
2. I also need to know which tubes are the best for a particular pre-amp?
3. how long do tubes last normally with 2 hours daily use?

Any other information you can offer would be greatly appreciated. Thanks so much all.
4. Does turning on and off the tube pre-amp hurt it?
rbwinterlink
Agree with Czbbcl.

If you buy used, then you can always change easily without a big financial hit. Just make sure you know what you're getting including which tubes and that you do not overpay.

The other technical factor to consider if you like is to match output impedance of the pre to the input impedance of your power amp.

A pre-amp with a lower output impedance may have an advantage for cleaner more dynamic sound depending on the actual input impedance of your amp. It might be worthwhile to know these numbers before deciding, all other things aside.
I suppose downunder refers to the location of your head so you should know bullshit when you see it.
Stanwal - you are a funny guy - not

why don't you keep your mouth shut and give your opinion when you have actually heard something you are dribbling on about, rather than relying on reviewer numbering systems.

Martin Colloms is a professional hifi writer and almost every new piece of cj or ARC equipment is so much better than the previous piece. or so you have to believe, otherwise he will be out of a gig
Downunder, when I want your opinion I will beat it out of you. Martin Colloms has been one of the most respected Audio writers for over thirty years while you are just some shithead.
Rbwinterlink,

1. Either will work well. You can't have someone else tell you what you will like best.

2. The 6922s are a fantastic tube to roll. You may want to go with a brand that is more sweet or more neutral. We have no way of knowing what you will want.

3. At 2 hrs a day, probably 5 to 10 yrs.

4. No, but don't turn it on and off several times a day. On when you want it on and off when you are done for the day. Someone will tell you to leave in on 24/7. Try it and see if does vs how it sounds after being on for 1 hr. Doing the math, 2 hrs a day = 730 hrs a yr. 24/7 = 8760 hrs a yr. Tubes don't last forever.

Other info: I don't think you can go wrong with either brand. Just get the nicest one you can and live with it.
Some day in the future you will get a chance to demo the other brand and if you like it better, make the change.

For the record, I own the CJ ART series 2 and the ACT 2 series 2, different, but love them both. I was surprised at Colloms ratings of the CJ's. He clearly favors the 6h30 sound over the 6922, rating the CT-5 way above the ART. That's his opinion, value it or not.

Keep in mind, when you ask what is the best "whatever", you're asking for opinions and you will end up with a poll. If 90% felt "a" was better than "b", that would be pretty convincing but you might be in the 10% group that prefer "b". Your system fits "your" ears/taste.