The Conrad Johnson PV-7 arrived today!

inspiredsports

I am so happy !!

I bought a vintage Conrad Johnson PV-7 tube preamp from a seller in California, and you just never know . . .

The pre was not in its original box, but looked like it was factory packaged with special wrap-around foam inserts and thick bubble wrap, so I immediately felt good when I opened the package.

Then I found a care package with sales literature, and a late 2006 receipt for repair direct from Conrad-Johnson Design, Inc., 2733 Merrilee Drive, Fairfax, VA 22031. The factory had serviced the power supply and replaced a resistor, regulator, some caps, resistors and transistors (a known issue with the PV-7). I'm guess the factory service explained the high-line packaging materials.

The factory had also replaced the 2 phono section tubes with matched Electro-Harmonix 12AX7EH ($22 each then, now about $12 so not very good tubes).

The line stage tubes were 1 unknown 12AX7, 1 unknown 12AT7WC and 1 unknown 12AX7-ECC81 W. Germany (no diamond). My Eico 667 tester arrives tomorrow, but will need going over so that won't help for a while either, but . . . . I had already planned ahead and new tubes are on the shelf.

I wanted to see what the tubes sent sounded like so I replaced the vintage Dynaco PAS-3 with 4 strong matched Telefunken 12AX7's that I bought in October with the Conrad Johnson and warmed it up.

Not so good. The Dynaco is amazingly sweet with those Telefunken Smooth Plates, and customizable with separate bass and treble controls for both channels, and I had it sounding extremely well tuned. Even after 4 hours, the PV-7 still sounded like dirt.

Ok, to the shelf. Forget incremental steps with various Sovtek, Phillips and Telefunkens from the Dynaco, tube RIAA and tube buffers . . . I went straight to the NOS Mullards!

I just scored a strong matched pair of 1960 British made Mullard military issue CV4024/M8162 "R" code tubes from the Mitcham, Surrey, England plant with the rare shield logo AND a strong matched quad of Mullard Blackburn 12AX7's so I have the sockets covered.

2 12AX7's went into the phono stage sockets, and 1 12AX7 and the 2 CV4024/M8162's into the line stage.

Patience . . . warmed it up for a good 15 minutes.

Oooh's and Aaah's !!!

This is an ancient, paltry little pre compared to what many here have, but I have to say, it just kicks butt! I've been at it with the Mullards for about 3 hours now and my biggest first impressions are that the soundstage is IMPRESSIVE, much DEEPER, plus the bass is livelier/faster.

It's a nice "next rung on the ladder" for me that I think I could be happy with for a long, long time. (and yes, I know, it DOES NOT have a remote). That would be my biggest gripe.

Like many here say . . . TUBES RULE !!

inspiredsports

Thanks Sal, I am smiling from ear to ear!

kawizx9r

That's great to hear!

Would love to take a step up the ladder to a better tubed pre myself someday......someday.

Btw, pics or it didn't happen! And yes, TUBES RULE!!!

-Freddy

vc69

Nice score. I really would love to try some better tubes in my pre. Soon I hope.
Pics would nice

F1nut

I knew you'd like those Mullards. Congrats on the new to you pre.

george daniel

Congrats on your aquisition,, the ranks of the tube heads are growing at an enormous rate.:)

inspiredsports

F1nut wrote: »

I knew you'd like those Mullards. Congrats on the new to you pre.

I'm looking for more of these because I don't think I ever want to be without them.

I don't know the proper words I guess, but the "holographic" or "3D" effect that this pre produces with these tubes is outrageous. And the tone is so pure. I've been at this now with the Mullards for almost 6 hours with ZERO fatigue.

inspiredsports

kawizx9r wrote: »

That's great to hear!

Would love to take a step up the ladder to a better tubed pre myself someday......someday.

Btw, pics or it didn't happen! And yes, TUBES RULE!!!

-Freddy

Photos tomorrow . . .

inspiredsports

george daniel wrote: »

Congrats on your aquisition,, the ranks of the tube heads are growing at an enormous rate.:)

It seems like turntables and tubes have been making a huge comeback for the last couple of years and I don't see it ending.

I just wish US companies could get energized and hold the far east stuff at bay, but I guess the current business climate is only going to deteriorate the way our elected clown prince and clown speakers are performing, but I can hope!

engtaz

Congrats. Enjoy the tubes.

leroyjr1

Lasareath wrote: »

i need a tube pre, I'm missing that Anthem that i had here for 4 weeks.

How did you like the Anthem compared to your Adcom GFP-750?

inspiredsports

I've recently seen some very expensive 12AT7/ECC81/A2900/CV6091 variants as follows:

--- GEC Genalex A2900 "Tri-Mica" ( WH Z & YD Z [Hammersmith, UK])
--- GEC CV6091 "Black Annode" (Z ^ 1967 - Code: YJ KB/Z)

Does anyone have experience with these?

inspiredsports

Wow, in just 24 hours those Mullrdss are really starting to bloom!

As promised, a few photos. The guts are nice, cover in 9/10 shape, and I don't think there is a blemish on the faceplate!

It's a catastrophe right now as the everything is being moved for wallboarding (over the block walls), a new rack and new carpeting, but I've attached the view from my desk.

Ern Dog

Nice score.

dorokusai

That's one of my favorite tube pre-amps.

inspiredsports

dorokusai wrote: »

That's one of my favorite tube pre-amps.

I just got the schematic from Conrad Johnson today (great customer service during a holiday week) and am amazed at how simple the circuitry is. I only wish they would have added remote control functionality and this one could have been it for a long, long time.

danz1906

Sweet-Congrats!

treitz3

New toys are cool. Congrats!

doctorcilantro

inspiredsports wrote: »

I've recently seen some very expensive 12AT7/ECC81/A2900/CV6091 variants as follows:

--- GEC Genalex A2900 "Tri-Mica" ( WH Z & YD Z [Hammersmith, UK])
--- GEC CV6091 "Black Annode" (Z ^ 1967 - Code: YJ KB/Z)

Does anyone have experience with these?

Shameless plug but audioclyde (at AC) sent me this after he got the kona-gold: Amperex 7062 d-getters (1960).

"I'm really impressed with the detail & soundstage right out of the box. The Gen A2900's (and Yellow T's for that matter) are soundstage champs, and really warm with full bass; these Amperex tubes seem to have a bit tighter bass, maybe a bit more detail and are soundstaging like crazy themselves!"

I sent some to Inspired but I didn't think to mention the taller bottle (duh). I wish you could have used these! I've been gathering feedback about these and independently hearing the same positive results. Now I just need an amp that uses 12AT7s LOL.

inspiredsports

doctorcilantro wrote: »

Shameless plug but audioclyde (at AC) sent me this after he got the kona-gold: Amperex 7062 d-getters (1960).

"I'm really impressed with the detail & soundstage right out of the box. The Gen A2900's (and Yellow T's for that matter) are soundstage champs, and really warm with full bass; these Amperex tubes seem to have a bit tighter bass, maybe a bit more detail and are soundstaging like crazy themselves!"

I sent some to Inspired but I didn't think to mention the taller bottle (duh). I wish you could have used these! I've been gathering feedback about these and independently hearing the same positive results. Now I just need an amp that uses 12AT7s LOL.

I sure wish they would have worked out as it sounds like a must-have tube for the 12AT7 socket arsenal! They were so close, within less than an 1/8" of fitting.

F1nut

Now I just need an amp that uses 12AT7s

Mine takes a quad, if you're still looking for feedback.

inspiredsports

I had to return some 12AT7-family tubes to DocterCilantro as they were taller than standard plain-jane 12AT7's and wouldn't fit in the PV-7. I asked him to surprise me with a replacement choice.

Well, today was Christmas in January!

First, I'd ordered 5 Herbies Ti-9 Tube Dampers for the PV-7 and they arrived today. These dampers are based around a spring-tempered titanium C-ring with polymer isolation pads surrounded by fiberglass/carbon microfiber sleeves to firmly grip the tube.

These dampers absorb micro-vibrations and simply cut microphonics out of the equation. To me, they allow the tubes to yield an even more focused soundstage than when used without. In my humble opinion, they yield a BIG Improvement

Next, the replacement tubes arrived from Jon, and they are well, . . . WOW tubes; a strong matched set of 1961 RCA 12AT7WA's with Triple Mica Black Wing Plates with square getters! I know these tubes are becoming very rare in 12AT7, and I believe even harder to find in 12AT7WA. At any rate, I think he upgraded me to a tube worth way more than what I paid for, and I owe him one.

THANKS DOC !!

I won't have a chance to remove the Mullard CV4024's and swap in the Wing Plates for a few day, and will report back when I've had a chance to give them a good long listen.

george daniel

hmmm,, somebodys'/:) having fun/excitied with tubes.

inspiredsports

george daniel wrote: »

hmmm,, somebodys'/:) having fun/excited with tubes.

In a word, Yes! And it sounds sooooooo good!

I'm blessed to be able to listen to music all day long while I work, and now with the holidays over, every one is back to work/school, I don't even need to worry about the volume.

MrIgotNomoney

Hello
Inspired, I have a PV 7 and am wondering if your power supply upgrade included a new pc board ??? my PV7 still has twist lock power supply caps.
bob

inspiredsports

The second image in post #16 above shows one view of the power section. Conrad Johnson Design did the upgrade and from memory I believe new components were simply added to the existing boards.

I recently sold the unit in thread at http://www.polkaudio.com/forums/showthread.php?t=103404 and I have more images at http://www.inspiredsports.com/images/cj-pv7/ including an image of the receipt listing the components CJ replaced which should be helpful.

If you search google for "conrad johnson PV-7 site: polkaudio.com" (minus the quotation marks and don't put the space between the colon and polkaudio.com) that will limit the search to Club Polk and will probably turn up at least a dozen good threads here.



P.S.: here's why I had to add the space in "conrad johnson PV-7 site:polkaudio.com" as a colon followed by a p is a smiley here in CP

MrIgotNomoney

Thanks
Im thinking of sending my pre back to cj for an upgrade. I thought the upgraded power supply board looked like a factory update.
bob

inspiredsports

MrIgotNomoney wrote: »

Thanks
Im thinking of sending my pre back to cj for an upgrade. I thought the upgraded power supply board looked like a factory update.
bob

You might also check out www.musictechnology.com. In my opinion, they are very, very good with CJ products and have former CJ personnel on staff.