Another important part is the power of your amp. Don't expect to hear your low B if you don't have at least 500 Watts and a cabinet designed to reproduce these lower frequencies. In studio or on records, you'll hear it, for sure, but on your 30 Watts Ashup, I'm not even sure you'll hear anything...
Ask Anthony Jackson what he's using live and you'll understand. By the way, the scale length is not THE solution, ask Ken Smith as he sticked to 34 inches scale and his basses have a very good tight low B.