Russian Pio caps

[EmiAba]

My Guitar tech gave me two Russian-made pio capacitors k40y-9 022uF. I've never used any of those. My favorites are orange drop. I would like to know what differences there are between these capacitors and Orange drops, and if it is true that they are less reliable in terms of durability than Sprague

 

[beaubrummels]

Paper in oil will dry out over decades, and during that process, subject to drift in it's capacitance value. Won't be immediate, and you may not even notice if it takes years to happen. As long as they are the same value 0.022uF, they will sound the same as an Orange drop that is 0.022uF.

Orange drops are polypropylene and very stable over their lifetime, resistant to weather/moisture/temperature changes.

There isn't an advantage to using PIO unless you enjoy knowing there are vintage-y parts in your guitar, and you don't plan to have it wired that way for more than 10-20 years of use and abuse.

 

[Clint 55]

To me, Pio sounds silkier and more vintage, while orange drop sounds fatter and more supple.

Que the hordes that think no way can different materials sound differently.

 

[eclecticsynergy]

I've used some older (I think) NOS green Russians. To me they sound fine.

 

[Mincer]

Sonically, I can't hear a difference. I'd find the value I like and use one that won't drift over time. I don't really care how a cap is made, as long as it is stable.

 

[Chistopher]

To me, Pio sounds silkier and more vintage, while orange drop sounds fatter and more supple.

Que the hordes that think no way can different materials sound differently.

The construction of a capacitor of a tone control that I usually have set to be 100% out of the circuit is not gonna change the fact that my tone is dialed to crap and my phrasing is uninspired.

 

[Chistopher]

I've also heard some here say about ceramic disk caps being more prone to certain issues, but I don't remember well enough to repeat it here

 

[ehdwuld]

I have PIO in my Ibanez RG2
if there is a difference, I cant hear it

But there again
You set the tone control at the beginning of the song
And usually dont move it during

So if you set either kind of cap at the beginning of the tune
No matter what its construction
you will set it by ear
So its sweep and such are not in anyway relevant

sweep is determined by the pot taper

I have heard the marketing
Its just marketing.
Buy our version, you'll like it better

 

[beaubrummels]

To me, Pio sounds silkier and more vintage, while orange drop sounds fatter and more supple.

Que the hordes that think no way can different materials sound differently.

I've also heard some here say about ceramic disk caps being more prone to certain issues, but I don't remember well enough to repeat it here

Years ago I made a little breakout box to test all these internet theories about how different caps sound different. I also just tested some various caps with alligator clips outside the guitar (which is how I started before I decided I needed to make a formal test rig). I put a variety of different caps (ceramic, polypropylene, paper in oil, etc.) on a rotary switch. I measured each cap and picked ones that were within ~1-2% tolerance of each other or so, but I measured down to 4 decimal places to assess if even that much value difference contributed to the sound. Below is the 250k Fender .047uF tone box I made, I also did Gibson 500k .022uF version.

What I found is that if the caps measured the exact same, there was no difference in sound. If the cap value was higher, then the rolloff was darker, if the cap value was low, then the rolloff was less effective (basically the corner frequency was higher so it didn't get as dark).

The one exception was little cheap ceramic disc caps. Those never gave me a consistent reading on their cap value, the value kept moving high or low on the meter, and subsequently, in circuit, they sounded murky and unclear, whereas any other cap, even though it rolled off highs, you could still hear all the notes clearly through the sound - like holding your hand over a high-quality speaker, you can hear everything clearly, it's just darkened or filtered. So I would recommend avoiding really cheap little ceramic discs, but other than that, you could use any cap type (polypropylene, paper in oil, ceramic, etc.) and get the same sound as long as the cap measures the exact correct value. The only other consideration is stability, like the issue PIO has with drying out which no other cap type has.

 

[Clint 55]

I notice the same tone color characteristics of each material regardless of what capacitance value it has.

 

[magillver]

That's really nice work, Beau! I have a buddy who works for the company that makes Emerson capacitors. He gave me a baggie of different caps to mess with, so I have them in several of my guitars now, and can't tell the difference. If they hadn't been free, I never would've paid $28 each for caps...

 

[GuitarStv]

In a guitar tone circuit, all caps of the same value sound the same. The PIO look cooler though, if that's important to you.

 

[EmiAba]

So to summarize, same value same tone regardless the material they are made of. The PIO are less stable and less reliable in terms of durability. Mmmh why they are so pricey? I mean, taking aside the vintage aura, what is the reason I do prefer them over all the others?

 

[Phantasmagoria]

Always thought PIO caps (I've only tried Russian. silver/green/red) sounded warmer/rounder & sweeter with more harmonics. Could be wrong but at two-three for $5 (what they used to cost) I felt they were worth it..

 

[freefrog]

So to summarize, same value same tone regardless the material they are made of. The PIO are less stable and less reliable in terms of durability. Mmmh why they are so pricey? I mean, taking aside the vintage aura, what is the reason I do prefer them over all the others?

IOW, you have tried the PIO caps and now you prefer it to the Orange Drops described as your favorite in the first post ? This is a friendly question: no irony in my words.

 

[Clint 55]

So to summarize, same value same tone regardless the material they are made of. The PIO are less stable and less reliable in terms of durability. Mmmh why they are so pricey? I mean, taking aside the vintage aura, what is the reason I do prefer them over all the others?

No. There are differences in tone. People have complexes about using their theory first and listening second. (Or not listening.) Pio aren't pricey, they cost a few bucks..

 

[freefrog]

Side note - Beau', whatever people think about tone caps, your experimental box has my respect : nice dispositive and methodology! For the record, an engineer named David Collins did something similar a while back:

https://youtu.be/817JHiYV_Po?si=lUEAnQnx13XPc6E2

Always thought PIO caps (I've only tried Russian. silver/green/red) sounded warmer/rounder & sweeter with more harmonics. Could be wrong but at two-three for $5 (what they used to cost) I felt they were worth it..

Thx for your testimonial.

FWIW and as an experimental echo to your post, I share below the harmonic response of a pickup electrically excited by a stable permanent 1130hz signal. The lines on the screen didn't vary once the exciter enabled. Blue line = the pickup linked to ground by a 120k resistor only. Red lines = the same thing with tone capacitors between the 120k resistor and ground (as with a 500k linear tone pot set @ 24% of its value).



I've selected screenshots involving a PIO and an Orange Drop to be on topic. Now, let's underline that in similar experimental situations, tone caps often behave like in the bottom pic (with a low pass effect expected from a tone capacitor) and that PIO doesn't always gives what the upper pic shows: there's a variability of discrete capacitors supposedly identical in such a case and it might explain why subjective experiences vary so much / why tone caps are such a can of worms in Web discussions (I had even forbidden to myself to talk about this online and I wouldn't be surprised to regret this post later but maybe it will make sense for some readers). ;-)

 

[freefrog]

... And to put things in perspective: below is the response of the humbucker pickup mentioned above when played in chords direct to the board (orange line), with its 120k resistor to ground (blue line) and without any resistor nor capacitor, in a "no load" configuration, as if the pickup had no tone control at all (red line).

 

[beaubrummels]

So to summarize, same value same tone regardless the material they are made of. The PIO are less stable and less reliable in terms of durability. Mmmh why they are so pricey? I mean, taking aside the vintage aura, what is the reason I do prefer them over all the others?

Price is likely a combination of materials and process necessary to manufacture, coupled with the 'vintage-accurate' buzz that makes them valuable to nerds and enthusiasts. You can certainly use PIO all you want, they're 'vintage-correct' or 'period-correct' for some guitars, and they'll be fine for quite a while. I wouldn't have a problem using them. It's just their lifetime is shorter than mylar and polypropylene, so just plan on replacing them after a while. But it's like decades out before you'll start having/noticing any change.

Unless you are Clint, and he hears a difference. Maybe you can also. Personally I wasn't able to detect a difference when the values were identical.

 

[beaubrummels]

FWIW and as an experimental echo to your post, I share below the harmonic response of a pickup electrically excited by a stable permanent 1130hz signal. The lines on the screen didn't vary once the exciter enabled. Blue line = the pickup linked to ground by a 120k resistor only. Red lines = the same thing with tone capacitors between the 120k resistor and ground (as with a 500k linear tone pot set @ 24% of its value).



I've selected screenshots involving a PIO and an Orange Drop to be on topic. Now, let's underline that in similar experimental situations, tone caps often behave like in the bottom pic (with a low pass effect expected from a tone capacitor) and that PIO doesn't always gives what the upper pic shows: there's a variability of discrete capacitors supposedly identical in such a case and it might explain why subjective experiences vary so much / why tone caps are such a can of worms in Web discussions (I had even forbidden to myself to talk about this online and I wouldn't be surprised to regret this post later but maybe it will make sense for some readers). ;-)

This is good and interesting stuff. Any chance you can overlay the PIO on the Orange, just the tone cap lines, to see the delta? Also, what were the exact values of the PIO and the Orange?