Repair or mod CJ PV-12?



The transformer on my Conrad Johnson PV-12 bit the dust. I'm debating whether or not to send it to CJ for repair, or off to get mods and a new transformer. If the mods included a transformer upgrade, that would be a fantastic choice.

Some people here have had good luck with mods, could they provide who did them; from what I've heard they got fantastic results.

Any help you can provide will be greatly appreciated.
orpheus10

Showing 11 responses by orpheus10


Tubegroover and Detredwings, thanks for the invaluable advice; I would replace the transformer my self if I could find one. CJ won't sell one, and I don't know where else to go.

Since the mod people can probably get a transformer, that could be included with the mod. CJ was not specific enough for me; while their minimum for inspecting the unit wasn't bad, there was no guarantee in regard to repair. There have been complaints (not against CJ) about no follow through after submitting up front money. New scams seem to be contagious and they come in waves.

I'll contact Bill Thalman in Virginia, and we'll keep each other posted on progress; thanks a lot.

While it's very unusual for a transformer to go bad it happened, one of the windings went open. This was very easy to confirm with an ohm meter. Replacing the transformer would be a piece of cake, especially since I left the color coded wires attached and dangling off their terminations.

After I direct CJ to this site, and they see what you guys think about them not selling me a transformer, we'll see if they have a change of heart.

Thanks for your support.

Detredwings, you brought up a very valid point, the "CJ glow" as we called it, is special, and does not exist on current models; they went to that sterile sound the reviewers decided was best. As we know, trombones sound "trombonier" and saxes sound "saxier" with these older CJ units; they seem to be especially voiced for jazz. While mods might give a better sound stage, there is the possibility of losing the "CJ glow".

I always come out ahead when I come to this forum for advice, while mods are a fantastic bargain in most cases, and could be in this case as well if you're not tuned to the elusive "CJ glow" that seems to be special for jazz.

Maybe after CJ see's this forum, they'll realize it's to their advantage to sell me the transformer.

Frogman, it's good to hear from you! I found George on "you tube", and he's pretty good on bass for a guy who builds amplifiers.

Thanks for your input.

Rok, it's good to hear from you. Once we've been to New York, they can no longer keep us down on the farm.

"Harmon Kardon", the high end of mid fi, right there at the top of "Stereo Review's" list. "Receivers"? Do they still make those?

Do you have anymore Sage advice for me? Since I haven't heard from you in awhile, I'm not going to tell you what I did with your last sage advice; anyway, it's still good to hear from you even if I have to tolerate a little "Rokism"; that's a category for anything that has no category, I say that falls under "Rokism".

Detredwings, all the people who can not hold a soldering iron or read a schematic think everyone else is so afflicted, consequently we have to overlook and at the same time understand the basis for their inability to comprehend what we have presented.

Frogman, no one has impugned CJ's reputation for refusing to sell me a transformer, we simply find it unreasonable.

I am a technician whose bad back is acting up, and to pack this unit and take it to the post office would be a hardship at the moment.

Detredwings expressed my position very well; replacing the transformer is easier than changing a tire for a technician; as a matter of fact, since I left the color coded wires dangling from their terminations, you could replace this transformer if you can solder.

In regard to the possibility of other problems, I isolated and confirmed the problem with my ohm meter. This case at the moment is in our court, and you have represented CJ with dignity, plus you've brought up valid points I don't disagree with; however, if CJ hears my point of view, as opposed to blindly adhering to policy, they will sell me the transformer.

Tubegroover, I also own a PV-10A and I have sent it in for mods and upgrade, plus bought sets of tubes. This is the first time me and CJ have conflicted; while it's good for a company to have a policy, I don't think they should blindly adhere to it in all cases.

In regard to Rok, I doubt very seriously if he's taking his own prescription and buying any of them "rustbuckets".

Tubegroover, I'm glad what you like best about your PV-9 was retained; for us that's a just right sound, we don't care about no stinking neutral.

I just got off the phone inquiring about the PV-12, and was told whoever takes care of it is out of town. No big deal, I wrote a letter and my unit is still at home. Although I wish I had the PV-12, I've still got the PV-10 working perfectly; still got that CJ sound we don't like to live without.

I want to install that transformer before I do anything else, maybe Bill Thalmann could get it, I'll call him

When your audiophile world is right, it seems everything else works out better; my advice to you is, ENJOY, ENJOY, ENJOY.

Tubegroover, I know exactly what you're talking about. I bought the original PV-10 that had apparent noise and distortion, but still sounded good. I sent it back to CJ where they made extensive changes to reduce both. I changed the electrolytic in the power supply to "Black Gate" to make it quiet as little mouse; so although it's changed, it's still the same.

Enjoy the music.

The PV-10 has received more accolades than any single pre-amp that I can think of. Of course as you go up in number, they cost more and sound better; but the PV-10 is the one more people have bought and heard, round the globe. We love our CJ's with the old school Golden Glow.

Enjoy the music