Sprague Black Beauty
Let's look at the different tone caps to make it easier for you to make the right choice. Knowing the correct value makes the process even easier and less expensive, because you can buy one cap of each type to try them out. Imagine buying all available caps in all values – the time and money saved is worth spending some time with our cardboard chart!
There are no hard and fast rules as to what cap to use – there are no good or bad ones. "Good" is what you like; if super-cheap, 2-cent mini ceramic caps sound good to your ears, there is no problem with that. I've seen some odd things inside guitars over the years, so experiment. One general rule to follow, however, is to use standard, non-polarized film and foil caps. Polarized electrolytic caps don't sound very good as a tone cap.
Some tone caps seem to be more common than others, so I've prepared a guide to these. Most of the information is based on my experiences or advice from customers. If you have any special questions about tone caps, feel free to contact me.
Sprague "Black Beauties"
These, together with the "Bumblebee" caps, are definitely the most discussed caps, with an almost magical touch to them. They are usually from the late fifties or early sixties and can be found in a lot of guitars from that era. They are famous for their use in '58 and '59 (Burst) Les Pauls, and some say that they are responsible for the magical tone of those guitars. The Black Beauties can be found with red and yellow print, and the 400 and 600 volt types are the ones most often found inside guitars from that time.
These caps tend to dampen some high-end, making the tone softer, smoother, warmer or sweeter. The bass frequencies are also smoothed out, providing familiar sounds from recordings of that era. These caps are for those looking for the old vintage Les Paul tone, and they can be found at NOS or used on eBay. The only replicas I know of are from LUXE, but keep in mind that these replicas will sound different, like newer bumblebee caps. If you want to use the vintage caps, make sure that you use vintage cloth wire inside your guitar and the Gibson fifties vintage wiring, otherwise you will not fully experience the tones from these caps.
"Bumblebee" caps
The bumblebee caps are very similar to the Black Beauties, and the origin of the nickname is pretty easy to see. You can also find these caps inside late-fifties Les Pauls and other guitars from that era, and they are definitely the most famous tone caps. Everything written about Black Beauties applies equally to bumblebee caps. Replicas are available from LUXE, Crazy Parts, and singlecoil.com.
One thing to be aware of is the Gibson "replicas" from their Historic series. These caps only look like bumblebees; I x-rayed and also opened some of them, and inside there is a cheap, standard film cap, masked with a Bumblebee cover.
"Tropical Fish" caps
These caps are called "tropical fish" because of the colored stripes that look a bit like a tropical fish. The "tropical fish" are often mixed up with the "bumblebee" caps, but this is simply wrong. You can find the tropical fish caps mostly inside old vintage stompboxes, wah pedals and amps, but they can also be found inside some guitars. I really like these as tone caps because they offer a very fat tone, without turning the tone into mud. These caps are no longer in production, so you can find them on eBay or from vintage parts dealers. R.G. Keen from Visual Sound investigated these caps and found that they are standard film caps that are just painted funny -- very similar to the cheap "Greenies" from Xicon, so give them a try.
"Flat Disc" (ceramic) caps
These are the old "high voltage" ceramic disk caps from Sprague or Erie that are found in almost every vintage Fender guitar. You can also find them inside old stompboxes and amps. They sound very different from modern ceramic caps and add a special flavor to the tone. If you are looking for a typical sixties vintage Fender tone, you should try these caps. From time to time, you can find originals on eBay, and replicas are available from LUXE. Another option is to get some consumer electronic devices from this era, like old TVs, radios, etc., and cannibalize from there. Often you can find them for free!
Sprague "Orange Drop" caps
These caps are still available today from Sprague/Vishay and can be found in some high-quality guitars from PRS or Gibson. You can find old Sprague Orange Drops in a lot of old Fender guitars. The higher voltage values can also be found inside high-quality amps today, as well as in a lot of vintage Fender amps. This is another tone cap that I really like; it's very transparent and tends to pronounce the mid frequencies a bit. A lot of our customers choose these caps for Fender guitars of all kinds. Old ones are available on eBay and new ones are available in almost every local electronic store. Don't skip trying these caps!
Mallory caps
Mallory caps have a tubular shape and yellow color. You can find these caps in a lot of amps, and also inside guitars as tone caps. These caps have a great fat and punchy sound, pronouncing the mid frequencies while keeping the treble alive. This is the ideal tone cap for rock guys, and a lot of our customers choose them for their Les Pauls and SGs. They also sound great inside Fender guitars, and Leo Fender put these caps inside all of his "Music Man" amps, manufactured exclusively for him by the Plessi company. This is a good overall tone cap, and a great place to start; it seems to work well with both humbuckers and single coils. You can buy these caps new from a lot of companies.
Silver Mica caps
These caps have a typical "hump" in the middle of the body and can be found inside high-quality amps and stompboxes. They can also used as a hi-cut cap on the volume pot and, if you can find the correct value, also as a cap for the tone control. Higher values are often hard to find, large and very expensive, but still worth a try. They really sound excellent, without any coloration of the tone.
Styroflex caps
Styroflex caps are easy to identify because of their tubular shape and transparent housing. These caps are typical caps from the fifties and you can find them inside almost every radio and TV from the era. Some companies still make them today, and they're one of my favorite tone caps for maximum transparency of tone with absolutely no coloration. I prefer Styroflex caps inside semi-acoustic guitars and jazz boxes. You can find them on eBay, usually as assorted sets of different values, but they are also available from some companies out of actual production runs.
Oil-Paper caps
These caps from companies like Jensen can be found in high-end HIFI gear, as well as in high-quality guitar amps. They are very expensive but a lot of players swear by them. You can use them inside guitars if you have enough space for them; I tried them a while ago, and they sounded very similar to the Silver Mica and Styroflex caps -- definitely not a bad reference.
There are a lot more caps out there, like the Vitamin Q, Mustard caps and many others, however I think this is a good overview to help you choose which ones to try. Caps sound very different from one another, and they really affect the overall tone of the guitar – even with the tone pot fully opened. Remember, there is no right or wrong, it is simply a matter of individual taste. Don't be afraid to try cheap or historically incorrect caps with "incorrect" values; I never use the factory stock values, as I find them to be way too much. I prefer values from 3300 up to 6800pF, which makes the tone control much more useable. You can also mix up different types and values in one guitar; I have a Strat with a 6800pF Mallory cap for the bridge pickup only and a 3300pF Mallory cap for the middle and neck pickups together. Feel free to experiment and let your ears decide!
Next month we will get back to doing some guitar mods, this time discussing the wiring inside your axes.
[Updated 11/23/21]
Orange Drop Capacitors
In a nutshell, a capacitor is an electrical/electronic device that can store energy in the electric field between a pair of conductors (called "plates"). The process of storing energy in the capacitor is known as charging, and involves electrical charges of equal magnitude but opposite polarity building up on each side.
Capacitors are often used in electrical and electronic circuits as energy-storage devices. They can also be used to differentiate between high-frequency and low-frequency signals. This property makes them useful in electronic filters, and that´s exactly what we use them for inside our guitars. Basically, our passive tone control can be used to dampen the high frequencies. When you close the tone pot, it rolls off the treble response, giving a more mellow tone. Adjusting this control affects the sound very noticeably, but it still is quite recognizable as the same guitar.
A basic rule for tone caps is that the bigger the cap, the darker the tone. Depending on the cap's value (capacitance), the effect can reach from "slightly warmer" to a "woman tone" all the way to "completely dark and clinically dead." Remember, the tone cap is always part of the guitar circuit and it even influences the tone when the tone pot is fully opened.
I often receive e-mails and calls from guitarists who don't use the tone control at all, mostly complaining about tones that are darke and lifeless, hotspots when closing the tone pot, and a basically useless taper of the tone control. I'm sure you've experienced the last problem; when closing your tone control, all changes occur between 10 and 8, and from 8 all the way to 0 there is no audible change of your tone. Don't worry, this can be solved. I hope that I can encourage you to give your tone control a second chance. It is really unbelievable how many tone colors can be easily dialed in with a proper tone control.
There are two basic parameters that we will talk about: the value (capacitance) and voltage rating of the cap, plus the type of cap itself. Both parameters will influence the tone a lot; this month, we will start with the value and voltage rating of the cap. Capacitance is a measure of the amount of electric charge stored (or separated) for a given electric potential. The voltage rating describes the maximum working voltage of a cap (potential, measured in volts).
Voltage Rating
One of my all-time favorite urban legends has to do with voltage ratings. You can read about voltage ratings of 400 volts – and higher! – for tone caps, and how this influences the tone. Do you ever talk about 400 volts coming out of your guitar? Of course not. Then how exactly does it influence tone?
As a basic rule you can say that every cap with a voltage rating of 0.5 volts or higher will work inside a passive electric guitar, with higher voltage ratings resulting in larger caps. The reason for the high-voltage tone caps that you find in guitars is easy to explain. A lot of popular caps, like the Sprague "Orange Drops," are for tube amps with inside voltage of 600V or higher. Nevertheless, the caps sound great inside a guitar, but an Orange Drop cap with a 10V rating would also sound great. A cap with a higher voltage rating does not sound different from the same cap with a lower voltage rating.
I've spent a lot of time with A/B comparisons, blind tests and measurements and I never could ear any difference. I'm not Eric Johnson, and I use my eyes instead of my ears to verify if the grass in my garden is growing, but you can try these tests yourself. Orange Drop caps are great for this experiment because they are available in voltage ratings from 100 to 680 volts.
Value (Capacitance)
Now that those rumors are debunked, let's focus on the more important parameter – the value of the cap. Remember our basic rule to help understand this parameter: the higher the capacitance, the darker the tone.
In the "golden days" of electrical guitars, Fender and Gibson used tone caps with a very high capacitance (0.1uf/0.05uF and 0.047uF/0.022uF, depending upon the time period). The 0.022uF value is still the standard today. If you need very dark and bassy tones, this value may work for you. For most of us, however, this value is much too large and the effect is more or less useless, resulting in the aforementioned problem of the effect only taking place between 10 and 8. The solution to the problem is simply a tone cap with a much smaller value. This little change will enhance the usability of your tone control dramatically, giving you a good evenness among the complete taper of the tone control without any hotspots, and every movement of the pot will result in a change of tone.
The value of your tone cap is always a matter of individual choice and needs, because everyone has a different ideal tone and everyone uses the tone control differently. Personally I use very small tone caps of 3300pF up to 6800pF, depending on the guitar and how bright it sounds. With these mall values I´m able to dial in a lot of tonal shades and colors all over the tone pot, and with every small movement the tone gets a little bit warmer and sweeter - not dull and dark.
Finding the Perfect Value
To find the perfect value for you, I suggest getting a piece of cardboard, two 10" pieces of wire, two solderable alligator clips and some cheap standard ceramic caps. The cheapest caps from a local electronic store are good enough for this, and the voltage rating is completely unimportant. Get values from 1200pF to .1uF, plus every value in between you would like to try. One piece of each value is enough. Glue the caps side by side on a piece of cardboard, with the legs reaching over the edges. Don't forget to note the value of each cap on the cardboard! Then, solder the alligator clips to the wires (one clip per wire, soldered to one end of the wire).
Now open your guitar and desolder and remove the existing tone cap. Solder the end of the wires opposite to the alligator clips to the points where the original tone cap was connected and close your guitar leaving the wires hanging out. Now you can change the different caps within seconds by simply connecting with the alligator clips. Play your guitar and use the tone control to see which value works best.
Hopefully you will be able to determine through this method what your favorite cap value is. My tip is to try 2200pF, 3300pF, 4700pF and 6800pF and listen to how they interact with the tone and taper of the pot. Chances are good that you will like them!
This is a very important step in converting your tone control to a useable and helpful tool in the future. Next month we will talk about the different cap types, and how to figure out which one is for you.
See you next month!
[Updated 11/23/21]