[BUILD] CAPI VP2X~500 Series~Preamp Kit~Official Support Thread

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jsteiger

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Hi all. I've built two VP26s and two VP312s, all with no issues, but now after maybe 2 years of working well one of my VP26 pres is very quiet and a bit distorted. Sound does pass through, but it's really quiet. I tried swapping out the opamp (Rogue Five DOA 1.3), tried a different slot in my 500 series rack (Vintage King Rack 500), but no luck so far. Any advice? Attaching a picture in case it helps. Many thanks for any ideas...
Most likely a bad solder joint(s) somewhere on the build.
 

malrooskee

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Hi there, just got my VP25 kits and while four of the five ceramic capacitors line up just fine with their identifiers, the C4 position one which should be an 82pF one has an identifier of 112J, whereas the build guide says it should be 82J. Like I was saying, the rest line up and this is the odd one out. Is this ok to install at C4?
 

jsteiger

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Hi there, just got my VP25 kits and while four of the five ceramic capacitors line up just fine with their identifiers, the C4 position one which should be an 82pF one has an identifier of 112J, whereas the build guide says it should be 82J. Like I was saying, the rest line up and this is the odd one out. Is this ok to install at C4?
If you look close with good magnification you will see what you think is "11" is actually a not so great "8". That said, the supplied caps are indeed 82pF and not 1100pF.
 

rockinrob86

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Tampa, FL
Hi all. I've built two VP26s and two VP312s, all with no issues, but now after maybe 2 years of working well one of my VP26 pres is very quiet and a bit distorted. Sound does pass through, but it's really quiet. I tried swapping out the opamp (Rogue Five DOA 1.3), tried a different slot in my 500 series rack (Vintage King Rack 500), but no luck so far. Any advice? Attaching a picture in case it helps. Many thanks for any ideas...

View attachment 92623
I fixed a few of these for a friend - his either had really low gain or were just cutting out. Some had dirty pads on the slot (scrubbed with toothbrush and alcohol) and the hardest one to get had a really dirty switch that shorted open. Finally got it situated and it was all good to go, has been working perfectly for a year or so now. They were a decade or so old and they smoked in the studio/car while carrying them in his lunchbox, so it happens.
 

Frank00

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Hi guys,

I'm about to acquire a Capi VP25 (rev B pcb) from a friend. It's looks fine but I noticed a slighlty odd thing.
It seems like the orange and green wires are swapped on the 2503 transformer side. This doesn't really match up with the Ed Anderson datasheet, or any 2503 pic I've been able to find (new, clone or vintage).
Is it a problem? Does it make a difference?

I attached a pic for reference.

Please let me know.

Thanks
 

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Frank00

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It looks like he followed the color code on the pcb side btw.
 

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Frank00

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I think the current one is Rev C for both VP25 and VP26. This one (Rev B) has the old faceplate too.
But if there was some errata on that REV that required a build change perhaps Jeff can weigh in here.
Yes, that would be awesome.
 

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Frank00

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Hi guys,

I just got Jeff's response via email, here it is.

Hi Francesco

Every now and again the lead order might be different. Internally all is the same so nothing at all to worry about.

Best regards, Jeff Steiger
Classic Audio Products, Inc.

Thanks a lot to Jeff for the super quick response. I hope this may end up useful to someone else down the line.

Cheers
 

Ricardus

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Hi guys,

I just got Jeff's response via email, here it is.



Thanks a lot to Jeff for the super quick response. I hope this may end up useful to someone else down the line.

Cheers
If it seems to be working right you should be fine. The only issue might be phase. Check to make sure input phase and output phase match.
 
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