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
those HIFICRITIC ratings are bullshit

The cj ART sounds better than either the ACT2 or CT5.
Yeah, I was heading down the CJ path for a tube pre-amp until I was quite disappointed with the controls and build quality for the price when I actually saw the newer units in person to the point that I was not motivated to stick around and listen. Then I saw and heard the ARC gear and never looked back and have had no regrets since.
My friends,

As you can see I am a guy who does not have the big money and is starting out to reach where many of you are. Presently, I must buy used audio stuff and am presently looking for the best Conrad Johnson or Audio Research pre-amp amongst the models I've mentioned above. What I urgently need is for someone to help me pick out from the models mentione the best that can be had. That is what I can afford at the moment. Thanks much to everyone.

Bob
They are both top notch companies with excellent products and support........ Cary Audio is another one........You will not make a bad decision irrespective of which one you choose .......... however they all have substantially different sonic signitures........so what someone suggests may not be what you are looking for sonically speaking.....
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.