Tube pre amp

disneyjoe7

Well it's mine I call him earlier tonight and he's not young, he doesn't sell nothing since he doesn't sell but buys new stuff to keep it forever. Not the cheapest pre amp, but I know what this pre amp can sound like.


http://www.audiogon.com/cgi-bin/cls.pl?preatube&1260765326&/Conrad-Johnson-PV-5-Tube-Pream

dorokusai

I've bought from zero(0)'s before but I know how to handle business...as a rule, just be safe and use communication and common sense as your guide. I was a zero on Audiogon, eBay and here one time....thank goodness that was ages ago

Congratulations Steve. It's about time you get off your **** in regards to audio....and you really don't have any excuses so save 'em. That's a wonderful pre-amp.

disneyjoe7

I know I heard this pre amp and my new Amazing speaker on PF04? at Troy's house, I never forgot it.

dorokusai

disneyjoe7 wrote: »

I know I heard this pre amp and my new Amazing speaker on PF04? at Troy's house, I never forgot it.

Yes, 2004.

vc69

Wow man, congrats on the score. I can't wait to hear what you think.
I have never heard any C-J stuff but I have stared at it and wondered.

Systems

I see another happy CJ owner in the makings. I wish we lived closer. You could scratch your amp itch with the borrowing of some MV75-A1, MV60SE, Premier 11, MV125 goodness. I still own quite a few other tube amps from other makers but I'm stuck on CJ for now.

REMEMBER! Be sure and check that this preamp has an inverted output signal. READ THE MANUAL! You will make all the connections as you would for any other standard preamp and connect to your amp as usual. All you need to do is reverse the speaker phase when connecting. + from amp goes to - on your speakers. If you use a turntable you'll also need to reverse the phase at the connections to the cartridge. Thats easy too using a small pair of tweezers or hobby pliers.

Don't forget to write a review.

Enjoy!!

janmike

Congrats Steve. Hope all works out.

Ricardo

187CAM wrote: »

REMEMBER! Be sure and check that this preamp has an inverted output signal. READ THE MANUAL! You will make all the connections as you would for any other standard preamp and connect to your amp as usual. All you need to do is reverse the speaker phase when connecting. + from amp goes to - on your speakers.

Unless you have SDA's, in which case you should NOT invert the wires at the speakers.

disneyjoe7

187CAM wrote: »

REMEMBER! Be sure and check that this preamp has an inverted output signal. READ THE MANUAL! You will make all the connections as you would for any other standard preamp and connect to your amp as usual. All you need to do is reverse the speaker phase when connecting. + from amp goes to - on your speakers. If you use a turntable you'll also need to reverse the phase at the connections to the cartridge. Thats easy too using a small pair of tweezers or hobby pliers.

Don't forget to write a review.

Enjoy!!

Do I need to worry if just 2 channel? I was thinking not.

Systems

Yes you do. Read the manual carefully. Then if you are still unsure call 703-698-8581. They are more than happy to talk about the older CJ units. They love to see them still being enjoyed. You can also contact Bill Thalman of Music Technology (703-764-7005) with questions. Be sure and ask about the inverted signal for the turntable on that preamp also.

Systems

From my PV12 manual:

MAIN OUT: Connect this output to the input of your amplifier (or crossover in a bi-amped system). We recommend the use of an amplifier with an input impedance of 20k ohms or higher. Since the PV12 line stage inverts phase, it may be necessary to reverse the connectons of your speaker leads to maintain correct phase. See the section on "Getting the Most Out of Your PV12" for an explanation.

Copied from the "Getting the Most Out of Your PV12" section:

The PV12 is phase inverting. If your system has an odd number of inversions, (for example, if the PV12 is the only phase inverting unit in the chain) then you must add one phase inversion. This is conveniently done by reversing the positive and negative connections to your speakers (be sure to reverse both channels).

vc69

I am puzzled by the phase inversion. Why would they do that? To avoid correcting it with more circuitry? Any idea?

Systems

Back in the day many components were phase reversed. Especially CD players.

disneyjoe7

Ok still confused about this phase inversion, why bother if the speakers are the only thing playing? It's not like you need to be in phase if you're the only one inverted.


God no I just didn't post that.

vc69

187CAM wrote: »

Back in the day many components were phase reversed. Especially CD players.

So, in short, C-J was compensating for a potential flaw in other components? Or is it a case of: Two C-J components would be "in-phase" without the need for for speaker wire inversion?

I am still puzzled by why they wouldn't just make their components phase aligned.

Systems

Call Ed at CJ and ask him. 703-698-8581 he has a simple explanation for this. Nothing to be worried about.

Ricardo

You can always ignore it. Having both speakers out of phase will give you the same sound anyway.

Those that say that they can hear a difference will chime in of course

Systems

Just enjoy the damn PV5. As stated in the manual you can switch between the phases to suit your listening.

disneyjoe7

187CAM wrote: »

From my PV12 manual:

MAIN OUT: Connect this output to the input of your amplifier (or crossover in a bi-amped system). We recommend the use of an amplifier with an input impedance of 20k ohms or higher. Since the PV12 line stage inverts phase, it may be necessary to reverse the connectons of your speaker leads to maintain correct phase. See the section on "Getting the Most Out of Your PV12" for an explanation.

Copied from the "Getting the Most Out of Your PV12" section:

The PV12 is phase inverting. If your system has an odd number of inversions, (for example, if the PV12 is the only phase inverting unit in the chain) then you must add one phase inversion. This is conveniently done by reversing the positive and negative connections to your speakers (be sure to reverse both channels).

I like the "May be Necessary to reverse the connectons", and yes I agree if you have the pre amp with other speakers working with other source pre amps, but if alone I don't see why.

Ok we cool.

reeltrouble1

[QUOTE=disneyjoe7;1175618 It's not like you need to be in phase if you're the only one inverted. [/QUOTE]

I could make so many funny Brett/Disney lines outta that one, signature stuff for sure.............

Your on your way, damm you stayed on that fence forever, there will be know turning back and this is a great way to jump into a tubed preamp.

RT1

disneyjoe7

It's shipped.

disneyjoe7

I got it today, and I say I can't remove the smile off my face. I'm in LOVE baby

hoosier21

disneyjoe7 wrote: »

I got it today, and I say I can't remove the smile off my face. I'm in LOVE baby

right on enjoy

disneyjoe7

Also must add this seller is OK with me, sweet condition never would believe this pre is 26 years old. More like new, not a mark on it, not even dust in the unit... nothing at all.

george daniel

Ricardo wrote: »

Unless you have SDA's, in which case you should NOT invert the wires at the speakers.

Which brings up a good point,, wonder how many SDA owners are using phase inverting pre's and don't know it?Also,, lets say you had a phase incerting pre with a dac that reverses phase in the chain,could you simply reverse the phase on the DAC to correct the inverted phase of the pre,,and thus use SDA's?
Congrats on the pre DJ,, is it in the Amazing's rig?
Enjoy.:)

Systems

I know the feeling. Give it a few days then write a review.

disneyjoe7

Yes the CJ PV-5 pre amp to a Parasound / Halo A23 amp to the Amazing speakers. I'm in LOVE.

janmike

Congrats on the new addition Steve. Enjoy.

inspiredsports

I decided to resurrect this not-so-old thread instead of starting a new one as my recently purchased (phase inverting) vintage Conrad Johnson PV-7 tube preamp arrives tomorrow.

I will be connecting the preamp to my SDA SRS 2's through a non phase-inverting amplifier, so by Conrad Johnson's instructions, I should be connecting red to black and black to red at the speaker terminals.

I noticed Ricardo (back in post #69) says DO NOT reverse speaker polarity if you have SDA's. Others say call Conrad Johnson or Bill Thalmann. I'm guessing after I go through all of that I will still have 2 (or more ) different opinions.

What have others in the group done in this situation, and what were the results?

Thanks in Advance,
Greg

george daniel

I have connected phase inverting pre amps to my SDA's unknowlingly,and knowingly, suffered no damage,, I have tried it both ways(switching speaker wire connections.), and could not really tell a difference.If you feel uncomfortable, then by all means contact Mr. Thallman first.IIRC, there was a C-J connected to Troy's SDA's at Polkfest,and I think it was phase inverting,,in fact it might have been Steve's.You might wanna shoot him a pm.For the record,my current pre in my SDA rig,does NOT invert phase.Keep us posted as to what you find out,please.