PIO caps

spi

Well-known member
I wouldn't normally post threads from TGP, but I thought this might be of interest to some of us electrical component nerds. Also as a heads up in case you were thinking or have used this product. Also because, drama.

Appears a company that sells wiring harnesses got caught with their pants down selling fake PIO caps.

"With genuine paper in oil capacitors" | The Gear Page

The company themselves respond with some unsatisfactory explanations/apologies about mistakes and blaming covid, without acknowledging that they were fraudulent (posts #22 and then #70).
 
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Nonsense? Because they tried both or because someone told them it was? I have a foil end tester, it's just a pedal with a three way switch to flip polarity and a couple alligator clips that put the capacitor in the signal circuit. You plug it into an amp to test a cap and place it next to a noisy RF source like one of those curly neon lightbulbs.

You flip the switch and the quiet side is the foil end, the one you put on the lowest impedance side of the circuit in a tube amp. Now PIO caps that I've tried were all the ones with their own farad shield, encapsulated in metal. These are SO QUIET that it is impossible to determine the foil end side unless you REALLY crank the amp.

Mojo dijons, on the other hand, buzz like a bumble bee (irony intended).

I have a friend that designs capacitors for the government. That's all she can say, because the government does top secret stuff. I told her about my cap experiment and she said "oh hell ya, the composition and shape of a capacitor makes a huge difference in audio signals, oh crap, you didn't hear me say audio"

The military has a you can't say what you can't say policy. It's not that she does work with audio, or doesn't work with audio signals because that's a clue to what she does and she can't do that.

Anyway, it's simple to try. Give it a go. I already know what your results will be because I found out accidentally while building amps, metal encapsulated PIO caps block stray signals from entering the signal path.

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I like PIO caps for guitar tone circuits. But I tend to mostly use NOS Russian KY series in most of my guitars. I think I have one guitar with a “ginooowine” Sprague Vitamin Q. I can’t hear any difference. Having said that, just for giggles I’ve put a few Tropical Fish caps in a couple guitars and they sound really good as well. 920D is pretty well known to be rip off artists for what they charge for harnesses anyway. This is no big surprise with the fake PIO.
 
I will also add, that if you can build a pedal then you can make your own pickup harnesses. There’s absolutely no good reason to pay someone $100 for a freaking Strat harness. Wiring schematics are all over the place to be had for every imaginable configuration (except @Feral Feline 's mythical Ibanez reverse phase wiring :LOL:)
 
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That's one of those gibson bumblebees in my PRS. Even worse it's one of the fake ones that made the Internet melt down. I took it out of my R7 after the story broke and as soon as I read it I realised someone had thrown a blanket over my amp 🤣

I genuinely didn't know any better so as I was annoyed with gibson I ordered some PIO caps and rewired it... And it sounded exactly the same as I remembered.

Recently I decided to remove the treble bleed and try 50s wiring on my prs and found the bumblebee caps when rummaging around my spares. I measured them and they were both bang on 0.022 so stuck one of them in. Personally I still think they look cool and it clearly works just fine.
 
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I posted in that thread. I want to know how the type of capacitor can make a difference in a guitar since all it does is bleed high end to ground. I did my own tests and couldn't hear anything. Even if you can hear a difference, it's a massive ripoff given the prices.
Didn't many old Fenders use lowly ceramic caps?
TGP is full of people who buy a Squier and want to install CTS pots but spend thousands on pedals with Alpha pots. I never got an answer form the guy of course.

As for harnesses, not only do pedal builders not need them but anybody else too. Why buy a wired harness when you still have to solder it to the pickups and ground wires? If you can't solder, your tech will have to do that so might as well have them build the harness from scratch with good components for a fraction of the cost.

I have saved hundreds if not more since I started learning guitar maintenance and a bit of pedal stuff. Lots more to learn but knowledge is power.
 
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