Mod your Conrad JohnsonPV10, PV12, Classic, Classic 2, ET3, ET5 etc.Conrad Johnson owners: turbocharge your preampIt's time to have the sound you want. Just tell us what kind of Conrad Johnson preamp you have, and what kind of sound quality improvement you want to hear. Call us at 302 723 7549. Bob Backe...625.00

Conrad Johnson owners: turbocharge your preamp [Expired]


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It's time to have the sound you want.  
Just tell us what kind of Conrad Johnson preamp you have, and what kind of sound quality improvement you want to hear.  Call us at 302 723 7549.

Bob Backert has been working on amplifiers and preamplifiers since the 1960's. Today, he mods tube preamps only.

If you have most any Conrad-Johnson preamplifier, you don't know **what a gem you really have** until you allow Bob Backert (founder of preamp manufacturer Backert Labs) to give it his gain stage mod. 
Bob named his modding business after his initials - Robert H Backert (RHB) Sound Dezign.  
The cost? In most cases, $625.
In our most recent Conrad Johnson ET5 mod -- a $10,000 reference preamplifier -- the customer wanted better sound, but he *really* wanted to extend tube life. The ET5 was “burning through” 6922 tubes rapidly.  According to the customer: 
“Tubes are spent within a few months, and sometimes only a few days or weeks”.

Luckily, our gain stage mod runs tubes more gently than in any preamp we have ever looked at. But would a $600 mod truly improve the sound of the $10K  ET5?  

Yes: 

“Hi Guys:
After a few days of listening, the ET5 sounds great. The bass is deeper and tighter, and imaging is more precise and more stable. I will defer any comment about tube life for a good 6 months. I installed a new Genalex 6922 and so far so good.
Thanks to Bob and Gary for helping me out with this. I was ready to give up on this preamp."

Sound quality advantages of a Bob Backert gain stage mod:
 - higher resolution
 - greater transparency
 - improved dynamics
 - better rhythm
 - increased soundstage width and depth

.... all, leading to more enjoyable involvement with your favorite music.

The primary mod that we do is to turbocharge your gain stage with the same circuitry used in Bob Backert's famous "Backert Labs" preamplifiers, which sell for $3,500 to $10,000 -- and they all use the exact gain stage that we provide in this mod. 
Let us know what kind of preamp you have, and what kind of sound quality improvement you want to hear.  We'll take it from there. 

RHB Sound Dezign, tel. 302 723 7549
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