With general improvement and Ra optimization (>90) for 2000-3000K models,
Now ZIGEN Dim to Warm COB series (ZG2) achieve >10% efficiency upgrade.
(e.g. ZG2BRG23L00 93lm/W 1180lm,13W)
ZG2 is based on unique patent granted structure to make dim to warm feature, and would help ideal CCT curve as shown below.
Please see here for more detail.