This advertisement was placed by Willoughby Gaspard Weiss in The Liverpool Mercury on 14 February 1843. It gives details of new music that he has available at his music saloon in Liverpool England, including "a set of beautiful waltzes, by A.S. Weiss of Mulhausen".
Yesterday I was researching Willoughby's youngest sister, Rosine Angélique Weiss, who was born and lived in Mulhouse. Apparently Rosine usually went by her middle name - she certainly seemed to prefer Angélique to Rosine - both her daughters had Angélique in their name - one as a first name, the other as a middle name, and she gave the name Rosine to neither. She married Jean Georges Schmaltzer in 1826, and it appears that at least in business, after his marriage, he often used the surname Schmaltzer-Weiss. This is not the first time I have seen a husband's surname tacked onto the surname Weiss - it appears to be a surname you would have wanted to be associated with in Mulhouse.
Putting this all together, it is possible that Rosine might have used the name of A. S. Weiss - Angélique Schmaltzer-Weiss... being born into the Weiss family there is every chance she also inherited the musical talents of her father and other Weiss relatives. Did she compose music? Surely a brother (Willoughby) might sell waltzes that you had written, capitalising on the surname Weiss (rather than Schmaltzer-Weiss), especially a brother who liked you enough to name one of his own daughters after you...
I have no concrete evidence that A.S. Weiss was actually Rosine, but there is a chance, and currently this is my best guess as to who A.S. Weiss was.