Soviet PIO Capacitors

We never cease to amaze ourselves with what we discover lying around in Monty’s HQ. We regularly open a drawer and find something special we’d completely forgotten about.

This is one of those moments.

We have a drawer full of genuine NOS Soviet-era PIO (Paper in Oil) capacitors, recently rediscovered in our workshop after many years tucked away.

These are the infamous caps originally used for missile guidance and submarine sonar back in the 70s, and they just happen to be perfect for vintage-style guitar wiring.

They’ve all been properly tested and are in perfect working condition, exactly as you’d hope from high-quality military-spec components of this era.

There are several different values and physical styles available, all with that unmistakable Soviet industrial charm. If you know, you know: these caps have a reputation for delivering a smooth, musical response with a natural roll-off that works beautifully in guitars. Warm, open, and never harsh.

This is new old stock in the truest sense. Not reissues, not replicas, not something we can reorder. Once they’re gone, they’re gone. No more hidden away in a drawer.

As always, we only sell components we’d be happy to use ourselves.

Monty’s approved.

What will they sound like and how can you use them?

The easiest way to think about how different tone cap values affect your tone is simple: the higher the number, the more high end is rolled off when you use the tone control.

Quick guide

0.022µF – classic, warm, vintage standard
0.015µF – balanced, vocal, sweet
0.01µF – subtle, bright, keeps clarity
0.1µF – deep, dark, old-school

0.022µF

The classic vintage standard

The go-to tone cap found in countless vintage wiring diagrams from the 50s and 60s. A 0.022µF value delivers a fuller, deeper roll-off and is famously at home in humbucker guitars and traditional 50s-style circuits.

Commonly used in Les Pauls, SGs, ES-style guitars, and Strats with a more vintage or blues-leaning setup. Perfect if you want the tone control to go properly warm and dark when needed, with a smooth, usable sweep.

0.015µF

Balanced, vocal, and beautifully usable

Sitting neatly between 0.01µF and 0.022µF, this value offers warmth without losing air or presence. It’s a popular choice in modding circles because it simply feels right in many guitars.

Often used on Strat and Tele neck or middle pickups, especially for players chasing rolled-back, vocal tones without things getting muddy. Ideal if 0.022µF feels a touch too dark, but 0.01µF a bit too subtle.

0.01µF

Subtle control without killing clarity

A favourite for bright guitars and players who want the tone control to act more like a sweetener than a blanket over the sound. A 0.01µF cap gives a gentle, musical roll-off that takes the edge off while keeping definition intact.

Commonly used on Strat or Tele bridge pickups, Jazzmaster lead circuits, or anywhere you want sparkle to remain as the tone control comes down. Perfect for players who actually use their tone knob and want fine control rather than instant darkness.

0.1µF

Deep, dark, unapologetically vintage

A proper old-school value with a big, deep roll-off. This is the kind of cap found in early Fender circuits and vintage bass wiring, delivering thick, woody tones when the tone control is reduced. Great for getting upright-style bass tones.

Often used in early Telecaster and Esquire wiring, bass guitars, baritones, or for dark jazz tones on neck pickups. Roll it back and it gets smooth, heavy, and unmistakably vintage.