Some general info about Guitar Tone Capacitors
A capacitor in a guitar circuit gradually bleeds the high frequencies to ground as the tone control is turned from 10 to 1 but even when dimed the capacitor is still in the circuit exerting some influence. But as you will read below you cannot exclude the potentiometer value form the discussion.
The value of the capacitor effects the rate at which this occurs so a 0.1uf cap will have a faster roll off than a 0.015uf cap but the overall tone remains the same with the same capacitor so for example a Jupiter 0.05uf, 0.022uf and 0.01uf will all have the same tone in the same guitar and setup but the rate of roll off of the high frequencies will be fastest with the 0.05uf cap and slowest with the 0.01uf cap, other brands will have different core tones, read on.
Different makes and constructions will have different core tones. The tone potentiometer value has a marginal effect on the mids but the value of the volume pot has a greater effect with a higher value giving a brighter tone so for example on a Strat there is a difference between a 250K pot reading 220-230K (slightly more mids) and one reading 250-270K (slightly more high end) and on a Les Paul a 500K pot reading 450-470K (slightly more mids) and one reading 500-520K (slightly more high end)and don't get me started on the period whan Gibson was fitting 300K pots to Les Pauls some of which were reading 270K!! (like you have a blanket over your amp).
As is well known the standard cap value for Strats, Tele, P bass and Jazz Base pickups is 0.05uf (some are rated at 0.047uf but don't forget that there is a tollerance to that value) and 0.022uf for P90’s and Humbuckers. We often suggest with Humbuckers to use a 0.022uf in the bridge and a 0.01uf-0.015uf in the neck as this will balance the tone control effect.
Don't forget that all capacitors come with a tolerance and as guitarists we work with and compensate for this.
You can use a 0.022uf or 0.033uf in for example Strats etc as this will soften the rate of roll off but you will ultimately reach the same place when the tone control is all the way down.
What is the difference between capacitor materials.
Ceramic Capacitors
Plentiful and inexpensive these are the default capacitor for many guitar manufacturers. Tolerance is generally quite high up to 20%. Their tone can have some harshness but remember that not all capacitors are born equal and it is how the high frequencies are bled to ground so for example Luxe ceramic caps perform very differently to other ceramic caps.
Polyester Capacitors
Use a polyester film as the dielectric material providing a low tolerance typically 5% or less, superior tonality and robust construction. Orange Drops, Sozo and Jupiter are examples of this type of capacitor. Jupiter caps are used by Collings and other high-end manufacturers.
Paper-in-oil Capacitors
Often referred to as POI caps, their construction with paper dielectric and oil impregnation results in a unique sonic character.
POI caps are known for their warm, rich and vintage like tone providing a smoothness and depth to the sound. The paper dielectric also contributes to a more natural and organic response, allowing for subtle nuances and harmonic complexities to be preserved. PIO caps are renowned for their excellent high-frequency roll-off, providing a rounded and sweet treble response without harshness. Moreover, these capacitors are often associated with vintage instruments, adding a touch of authenticity and nostalgia to the overall playing experience.
Luxe Paper-in-oil Capacitors
In addition to the above these are made the funky old school way, so they will leak voltage and play all kinds of other tricks on your digital multi meter, but rest assured, they've been tested every step of the way on dedicated capacitance bridges, and they will do just what they were made for when you wire them into your guitars. The weird things that play games with your multi meter are the same things that give Luxe caps their unique sound.
Just remember that they leak voltage, so these are only for guitars!
