Telicity: Difference between revisions
No edit summary |
No edit summary |
||
| Line 1: | Line 1: | ||
'''Telicity''' is a property of [[EDO]]s, which involves the given EDO being able to stack a number of instances of a given prime's [[patent interval]] to connect with an interval belonging to a chain created by lower prime's [[patent interval]] without either accumulating 50% relative error or more at any point in the process on the part of either prime's patent interval chain, or, creating as mismatch in results between the [[direct mapping]] and the more complicated traditional mapping for any interval along the chain. Furthermore, since the 2-prime simply results in manifestations of the [[unison]] at different registers, thus leading to things like [[octave reduction]], the 2-prime is not a factor that affects what qualifies as telicity ''unless'' an interval in 2-prime chain itself serves as the target, or '''telos''', of a higher prime's patent interval chain. Given this, any sort of telicity involving the 2-prime cannot afford to temper out commas greater than half an EDO-step in size due to the unison being such a foundational interval to both EDOs and JI, and, the resultant inability to temper out commas greater than half a step in size without exceeding the 50% relative error threshold. Therefore, for the sake of consistency in definition, the commas that can be tempered out to achieve telicity ''must'' be less than half an EDO-step in size. | '''Telicity''' is a property of [[EDO]]s, which involves the given EDO being able to stack a number of instances of a given prime's [[patent interval]] to connect with an interval belonging to a chain created by a lower prime's [[patent interval]] without either accumulating 50% relative error or more at any point in the process on the part of either prime's patent interval chain, or, creating as mismatch in results between the [[direct mapping]] and the more complicated traditional mapping for any interval along the chain. Furthermore, since the 2-prime simply results in manifestations of the [[unison]] at different registers, thus leading to things like [[octave reduction]], the 2-prime is not a factor that affects what qualifies as telicity ''unless'' an interval in 2-prime chain itself serves as the target, or '''telos''', of a higher prime's patent interval chain. Given this, any sort of telicity involving the 2-prime cannot afford to temper out commas greater than half an EDO-step in size due to the unison being such a foundational interval to both EDOs and JI, and, the resultant inability to temper out commas greater than half a step in size without exceeding the 50% relative error threshold. Therefore, for the sake of consistency in definition, the commas that can be tempered out to achieve telicity ''must'' be less than half an EDO-step in size. | ||
Commas that join prime chains together when tempered out are called '''telic''' commas, and each telic comma has an effective range called the '''telicity range''', and the size of a comma's telicity range is negatively correlated to the size of the comma itself – that is, the smaller the comma in question, the larger the size of that comma's telicity range. The size of a comma's telicity range is evaluated by comparing the size of a given EDO's step with the size of the comma in question – if the comma is more than half the size of the EDO's step, said EDO is outside the comma's telicity range. For example, [[81/80]] has a telicity range of 27, as 27 is the largest EDO with a step size that is more that twice the size of the comma, while [[Mercator's comma]] has a telicity range of 165, as 165 is the largest EDO with a step size that is more that twice the size of that comma. In addition, the concept of telicity can be used to evaluate the usefulness of EDOs relative to the [http://musictheory.zentral.zone/huntsystem2.html#2 JND] of human pitch perception, and, since an interval smaller than 3.5 cents is unlikely to be noticed by even the most trained listeners, it can be said that the JND has a telicity range of 171, meaning that EDOs that are higher than [[171edo|171]] are not all that suitable for use as musical systems outside of pitch bends. | Commas that join prime chains together when tempered out are called '''telic''' commas, and each telic comma has an effective range called the '''telicity range''', and the size of a comma's telicity range is negatively correlated to the size of the comma itself – that is, the smaller the comma in question, the larger the size of that comma's telicity range. The size of a comma's telicity range is evaluated by comparing the size of a given EDO's step with the size of the comma in question – if the comma is more than half the size of the EDO's step, said EDO is outside the comma's telicity range. For example, [[81/80]] has a telicity range of 27, as 27 is the largest EDO with a step size that is more that twice the size of the comma, while [[Mercator's comma]] has a telicity range of 165, as 165 is the largest EDO with a step size that is more that twice the size of that comma. In addition, the concept of telicity can be used to evaluate the usefulness of EDOs relative to the [http://musictheory.zentral.zone/huntsystem2.html#2 JND] of human pitch perception, and, since an interval smaller than 3.5 cents is unlikely to be noticed by even the most trained listeners, it can be said that the JND has a telicity range of 171, meaning that EDOs that are higher than [[171edo|171]] are not all that suitable for use as musical systems outside of pitch bends. | ||