Every oud is different, and what works well on one oud may not work the best on another. Manufacturers may offer several different sets classified by tension or tuning or scale length or a combination of these factors, sometimes throwing in misleading terms that tend to confuse more than explain. Or they may offer as little as one set. But it's really a "best-compromise" on their part, and understandably so, given the great variations between ouds.
Depending on your instrument and your own demands and tastes, these sets may be just right. Sometimes however, they are indeed a compromise.
Read on for specific information about tunings, scale length, tension and materials. The only sure method for determining the best strings for your oud is to try some different sets.
Most accomplished oud players will have customized sets to their oud and preferences. We offer many options in our various customizable sets, and are happy to help you figure out a fully customized sets.
In our experience, the overall best strings available are the Pyramid "Lute" strings. There are no one-size-fits-all options, each set must be custom configured. They are the most expensive commonly used strings, but I have never heard them sound anything less than excellent on any oud, and they are fairly long-lasting. That said, many other strings can also sound excellent, and sometimes a combination of strings from different manufacturers will be just what you're looking for.
For what it's worth, the most popular prepackaged strings for Arabic oud are the Aquila 13o, the Pyramid #650 and the LaBella OU80A. The most popular prepackaged strings for Turkish oud are the LaBella OU80 and the D'addario EJ95.
The best value in our opinion are the LaBella custom sets we offer.