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For Violin or Viola KSAA

The Kaplan ball-end adaptor allows ball-end violin and viola strings to be used with loop end hook-type fine tuners. The adaptor is small and discreet, with a polished gold finish. It preserves the alignment of the string from tuner to bridge. Each package contains five adaptors.
  • Violin
  • Viola
$5.99 Or 1,000 PTS
Players Circle Code Value: Not Applicable
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The Kaplan ball-end adaptor allows ball-end violin and viola strings to be used with loop end hook-type fine tuners. The adaptor is small and discreet, with a polished gold finish. It preserves the alignment of the string from tuner to bridge. Each package contains five adaptors.

  • Five adaptors per package
  • Polished gold finish
  • Allows a ball end string to be used with fine tuners that contain a loop end hook
  • Suitable for violin or viola
  • Designed and manufactured in our New York facility


String Comparison Chart

Silk Color Chart

Orchestral Strings, Simplified


What is string tension?

String tension is a measurement of force along the length of the string, from the bridge to the nut. It is determined by the amount of mass (material) wound on the string, the frequency of vibration, and string length. String tension affects the response, playability, and the sound of a string. We offer most of our string lines in multiple tension grades: light, medium and heavy tension. Stringed instrument makers use the term "tension" to describe the force exerted by the strings on the body of the instrument, however this is a different measurement than that of the playing tension referred to as "light," "medium," or "heavy." This force is determined by the string's playing tension, the angle of the strings over the bridge, and the geometry of the instrument.


Is string gauge the same as string tension?

No. String gauge refers to a string's diameter (width). One gauge unit equals 0.05mm in diameter. For example, a string that measures 15 gauge has a diameter of 0.75mm or 0.0295 inches.

For strings made with the same construction specifications, larger gauge strings will yield higher tension because of the added material and mass. However, string diameter cannot be used by itself to determine playing tension, since modern strings are made using a wide variety of materials with different densities. At D'Addario, we prefer to specify a string by its playing tension and diameter, rather its gauge.


Which tension should I use on my instrument?

We advise you start with medium tension. If the string feels soft and you need more sound, try heavy tension. If there is plenty of power but you want an easier bowing response, try a lighter tension. Sometimes, a mix of light, medium and heavy tension strings will work best for your particular instrument.

NOTE: There are no universal standards for tension levels, and that tensions will differ among string brands.


How does string tension affect sound quality?

The amount of tension on the string affects its sound. Heavier tension strings generally play with additional volume and projection, but are more difficult to control. Heavier tension strings have a slower bow response than medium or light tension strings of the same material. Lower tension strings have a wider tonal palette than higher tension strings and can be played more quietly. Contrary to common belief, higher tension strings don't necessarily sound brighter. Since higher tension strings can be played louder, players often bow further away from the bridge and use less bow pressure, which produces a less bright sound. 


Is string playing tension the same as the tension on an instrument?

Not necessarily. Players often use tension to describe the feeling of a string to both the left and right hand. This feeling is determined not only by a string’s playing tension, but the elasticity of the coe, the string diameter, the string texture, and the height of the string above the fingerboard. Violin makers also use tension to describe the force exerted by the strings on the body of the instrument. This force is determined by the string's playing tension, the angle of the strings over the bridge, and the geometry of the instrument.


What units do you use to measure string tension?

The official International System of Units (SI) for force is Newtons (N). We follow the conventions and traditions of the string industry in using pounds (lbs) to specify string tension in English units, and kilogram-force (kg) or kilopond (kp) to specify string tension in metric units. The conversion factors are: 1 lbs = 0.454 kg (or kp) = 4.448 newtons (N)

We measure string tension using a force sensor called a load cell. The end of the string is attached to the load cell sensor, the string is brought up to pitch at the specified vibrating string length, and the tension recorded. 


How do I determine what size strings my instrument needs?

Click here for our string selection guide.


My string broke as soon as I attached it! What happened?

First, make sure you have identified and used the correct string. Always lubricate the bridge and nut notches with pencil lead so the strings can move freely. Make sure these notches are cut correctly by your violin maker. If the problem persists, consult your violin maker.


The strings on my instrument are two years old, but I play my instrument infrequently. Do they need to be replaced?

Strings that are installed on an instrument will eventually wear out since they are under tension and exposed to humidity and corrosive pollutants in the air. Even if you play infrequently, you should change the strings on your instrument every year for violin and viola, and every two years for cello and bass. If you are storing your instrument for extended periods, loosening strings by a whole step can increase string life. However, be aware that this can cause the bridge and soundpost to fall down. 


My unused strings were purchased many years ago - can they still be used?

Unused strings, when stored in their original packaging, can last up to 4-5 years. It is important to store strings in sealed packaging to prevent exposure to humidity and corrosive elements in the air. Note: Steel core strings last longer than synthetic core strings due to their materials.


What is the difference between steel and synthetic core strings?

1. Steel core strings generally have a clear sound. They can be made with smaller diameters than gut or synthetic strings, resulting in an easier bowing response. The flexibility of stranded steel cores adds greater sound variety, tonal depth, and ease of bow response, especially for the lower instruments.

2. Synthetic core strings can be made to have a wide variety of tonal depth and bow response, ranging from very bright and soloistic to very dark and mellow. In general, these have a richer, more complex sound than steel strings. These are very resistant to climate and temperature changes. Some synthetic core strings are made to replicate the sound and feel of gut strings.


How do different materials affect my playing and/or my sound?

A string's design, materials, and construction affect its sound and response. Every string has a specific recipe, determined by months of research and testing. Most strings fall into one of three core categories: gut, synthetic, or steel. The core and windings are the most central part of the string and have the most influence over the sound and feel of the string. Winding is made from a range of metal or synthetic materials which add mass to the string while allowing it to retain the flexibility necessary to vibrate properly. Winding (or wrapping) is one or more layers of material wound around the length of the core. For information on how to select strings, click here.


What causes a string to sound false?

There are a couple factors that can make a string sound false. They are:
1. The instrument body alters the string frequency through the bridge when a note is close to such a resonance 
2. Dirty strings or strings with buildup. Finger dirt and rosin can build up in-between the windings, making the string sound false.


Why do strings matter?

Strings improve the sound and response of your instrument. It can be very difficult to produce an acceptable sound with the use of old or cheaply-made strings. D’Addario makes a wide variety of strings with different sound and response characteristics, allowing players to find the string that best matches their instrument and playing style.




How frequently should I replace my strings?

We recommend that with frequent use, you change violin or viola strings every 3-6 months, and cello or double bass strings every 6-12 months. Less frequent use (such as beginning student-level playing), strings may last slightly longer than this guideline. Strings that are installed on an instrument will wear out eventually since they are under tension and exposed to humidity and corrosive pollutants in the air. You should change the violin and viola strings at least every year, and cello and bass strings every two years.

Signs that it's time to change your strings include:
-  The inability to hold pitch for a long duration
- A dirty or grimy appearance.
- A dull sound

NOTE: If you can't remember when you last changed them, it's probably time to put new strings on! For more information on the various types of strings and how they affect the performers sound please click here.


What should I keep in mind when changing strings?

1. Change only one string at a time. Don’t tune down the other strings–you risk movement of the bridge or sound post.
2. When winding the string around the peg, try not to wind a string around or across itself. Let the string lay side by side on the peg if possible. This will minimize the probability of damaging or breaking the string.
3. Lubricate the nut and bridge notches with graphite (pencil lead).
4. Pay close attention to the bridge: when viewed from the side, the bridge should be perfectly perpendicular with the top of the instrument, forming a 90 degree angle. If the bridge is slightly tilted, it may be possible to straighten it, however this requires some training and experience. Your instrument repair technician can show you the proper way to straighten your bridge.


How can I extend the life of my strings?

The more care that you take in maintaining your strings, the longer they will last. 
1. Wipe down your strings after each use.
2. Do not repeatedly tune strings above their intended pitch because it can prematurely stretch a string or cause it to break. 

NOTE: If you can’t remember when you last changed them, it’s probably time to put new strings on.


What is the best way to clean my instrument’s strings and body?

Wipe down the fingerboard and bowing areas of your instrument regularly with a dry, clean cloth to help prolong string life. Don't use alcohol or other chemicals–they could drip on the instrument and permanently damage the varnish. To keep your strings and your instrument clean, apply rosin sparingly. Only a few (3-4) swipes are necessary before each playing session. Any additional applied rosin applied will fall off of the bow hair and onto the strings and body of your instrument.


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