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CJ PV-12 mods & upgrades by Bob & Gary Backert

I recently shipped my 15 year old CJ PV-12 preamp to Bob & Gary Backert of RHB Sound Design to have a few modifications and upgrades installed on the CJ.

My very first conversation I had with Bob was very enlighten to say the least. I informed Bob, I would be using the CJ PV-12 preamp for my phono stage only with the VTL 7.5 preamp. To make a long story short Bob & Gary completed their modifications on the line stage, phono stage, caps, gold/silver wire, power supply & IEC conversion.

Father & son went further to build a custom head amp stage, to increase the gain so I would have the ability to use a Dynavector 0.3mV. The technical construction completed by Gary is flawless and his soldering skills are impeccable. Gary’s workmanship is actually beautiful to look at. This is one heck of a father and son team.

Bob suggested that I listen to the CJ’s line stage before strictly using it as my phone stage only. So agreed to listen and it was magical.

If I could only use one word to describe the performance of my CJ PV-12 with RHB Sound Dezign’s modifications that word would be “Heavenly.”

The bass the highs the lows the midrange the vocals the sound stage the imaging have all vastly improved and it’s so much more transparent, liquid. and dynamic.

For the record I have not listen to the VTL since I setup the CJ, simply because the CJ is blowing it away. I know some of you may find this hard to believe but if I didn’t hear it for myself I would not believe it. The CJ’s dynamic linearity is stellar in all aspects. Well I guess I’ll be boxing up the VTL getting it ready for RHB Sound Dezign modifications and upgrades.

The CJ will be performing constantly for the next week or so to allow the V-Caps, wiring and all modifications to break-in nice & smooth for my musical enjoyment.
Bob & Gary, keep up the great work you are truly the man.
jmo
mrjstark
1,112 posts
 
Yup, G.& B.Backert......are Bob mods overrated ???
Absolutly not. Worht it ??? Yep. Would I do it again ???
Yes I would. Will I hear the difference ??? You will not only hear it but you will also feel it.
After Bob's modifications, my Consonance Cyber 800 turn into the monster and it is one of my favorite components in my system and I doubt that I will ever put it up for sell. It became the conversation piece and those who heard them agree that it is on par with the best.......whatever that means. I believe that it would be impossible for me to find a better amp for less the 10K......or even more. There is nothing that I can think of that could possibly improve the sound of Cybers except PC and tubes.......like Mullards for exemple.
phaelon
1,054 posts
 
Hi everyone,
I'm currently waiting to take delivery of vintage conrad johnson Premier V mono blocks to replace a cj Premier 11a. While I'm confident the gain in power will out way any deficiencies of an older cj design, I'm very interested in modification options that will improve speed, detail and performance at the frequency extremes without interfering with conrad johnsons house sound or unique virtues. In other words, I guess I'm looking for the Premier V that conrad johnson might make today. I'm particularly interested in an upgraded power supply and V-Caps, but I've been informed that V-Caps are hideously expensive. Any comments will be appreciated, except the most obvious one: At least wait until you hear the amps before you start talking about modifications idiot.
phaelon
1,054 posts
 
Good gravy! I really am an idiot - Of course I meant to write "outweigh" instead of "out way". Let this be a lesson to all you kids out there: Stay in school!
mrjstark
1,112 posts
 
My best advise would be to wait .......then listen....and listen some more. Roll tubes, play around with cables to tune CJ to your taste. Only then and only if.......there is area that you feel needs attention and no matter what you do - you can not achive that last refindment and magic , give Bob a call. I should also mention that Bob is very, very knowlodgable when it comes to CJ gear and no need to worry about lost of signature house sound characteristics.......just explain what are you looking for with this mod and let Bob do what he does best.......- puts smaile on his costumers face. If you decide to do it be prepare to spend some extra money for wiring upgrade with his silver/gold plated wire, I did not opt. for that upgrade but I keep hearing from others that it is a worthy move.

Enjoy your amps .......and call Bob for advise and recommendations.

Cheers

Mariusz
jmo OP
115 posts
 
Mrjstark,

The silver/gold wiring modification/upgrade is well worth it, that was one of the many upgrades I had Bob complete on the CJ PV-12. Phaelon, the V-Caps were another dollar well spent. I'll be sending Bob & Gary my amp for the following modifications..

1. IEC Upgrade
2. Power Supply
3. Gold/Silver Wire
4. (1) Internal 1/2 amp FB HiFi turning fuse I have already replaced the other (5) HiFi tuning fuse.
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