No real brand onthe ones I love - these have the acid you are talking about Marilyn
They are a 'generic' looking white label with red tomatoes (not a pix but just a print - almost like old printing) on them that say San Marzano and then depending on the type, they have a band at the top and bottom in a color - green for whole, blue I think for crushed, etc. I just wet and looked at them for a brand name and found that they are imported by Simpson out of NY.
I never buy anything but whole - I crush them myself - better quality tomatoes go into whole tomatoes. These ar perfect for everythinhg I make and I always keep them on hand. Not cheap though - a tad more than Hunt's or something but definitely worth it. The Muir Glen get the vote from both CI and Consumer Reports if I recall correctly but these are better.