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 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.