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  1. #1
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    Tube question guys

    My new preamp will have a higher output voltage, will this be cause to re-bias my power amp?

  2. #2
    Phila combat zone JoeE SP9's Avatar
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    No. The bias adjustment on a power amp is for balancing the push and pull of the output stage. The higher absolute output voltage level of the new preamp will have no effect, per se. A lot of tube preamps have high output voltages. I've seen them as high as 20 volts. When you combine that with the necessary current, you have the ability to drive long IC's and weird loads.
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  3. #3
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    Thanks JoeE. I got the new one in today. I just plugged it in and will let it warm up some before trying to turn it on and listen.

  4. #4
    Forum Regular harley .guy07's Avatar
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    Is your new preamp a CJ unit as well? I am just interested in what you are upgrading to.

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  5. #5
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    Yes, it's a CJ CT6. Haven't listened much yet but first impressions are good.

  6. #6
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    Congrats Mr. P. I hope you enjoy your new purchase. I'm anxious to hear how this compares to your PV14LS2.

  7. #7
    Shostakovich fan Feanor's Avatar
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    Quote Originally Posted by JoeE SP9
    No. The bias adjustment on a power amp is for balancing the push and pull of the output stage. The higher absolute output voltage level of the new preamp will have no effect, per se. A lot of tube preamps have high output voltages. I've seen them as high as 20 volts. When you combine that with the necessary current, you have the ability to drive long IC's and weird loads.
    Makes sense. For a given volume of sound, the power amp will "see" the same voltage from the new pre as from the old, it's just the new pre's output will be more attenuated vs. its maximum.

  8. #8
    Shostakovich fan Feanor's Avatar
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    Quote Originally Posted by Mr Peabody
    Yes, it's a CJ CT6. Haven't listened much yet but first impressions are good.
    Just two words, Mr P: tube rolling.

    Enjoy!

  9. #9
    Forum Regular harley .guy07's Avatar
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    Quote Originally Posted by Mr Peabody
    Yes, it's a CJ CT6. Haven't listened much yet but first impressions are good.
    Cool sounds good. Let us know what you think after some listening but knowing the Conrad johnson reputation you will probably be quite happy with your purchase.

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  10. #10
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    I didn't realize I had to put the tubes in, the PV14 came with them, or it, installed. You remove four screws, lift off a panel on the top of the preamp and pop the tubes in. Tube rolling would be very easy. I may not mess with that until checking into warranty issues. The tubes came with the silicone rings to place around the tubes to minimize effect of microphonics. By the time I got everything set up it was late. I did listen a bit, I had to

    First impression the sound is different, more toward neutral, better bass control, more nimble and better detail. The CT6 gives a live feel but not as "glowing" or what may be referred to as euphonic as the PV14. There are other differences but I don't have words to describe them. It's mainly sound stage characteristics. It's definitely a deeper feel, if that can be believed. On one disc the background singers were more toward the front and involved in the performance.

    I only had a very short listen. My little girls winter program at school is tonight but afterward you know where I will be and I will post more impressions later.

  11. #11
    frenchmon frenchmon's Avatar
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    Hey...This Saturday Mr.P...its you and I in your two channel/Home-theater room and your new Conrad Johnson....I'm bringing some Pat Metheny and some old school Lee Morgan....o yeah, We can do a shootout with the Analysis Plus to see if its all in my head about that cable. See ya tomorrow.


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