The invention provides a lighting device configured to provide white lighting device light, the lighting device comprising (i) a light source, configured to provide blue light source light, and (ii) a luminescent material element, configured to absorb at least part of the blue light source light and to convert into luminescent material light, wherein the luminescent material element comprises a luminescent material which consists for at least 80 wt. % of a M2-2xEu2xSi5-yAlyOyN8-y phosphor, wherein M comprises one or more of Mg, Ca, Sr, Ba, with a molar ratio of (Mg+Ca+Sr)/(Ba)≤0.1, wherein x is in the range of 0.001-0.02, wherein y is in the range of ≤0.2, and wherein the white lighting device light comprises said blue light source light and said luminescent material light.