Korg own both Spector and Aguilar. It simplifies their supply chain to use in house brands and there's also no benefit in them trying to make their cheaper basses sound like the expensive ones.
I had a 5 string for a few months. Great build quality and having also owned a Sire a while ago I would say that the Gloxy was much better. Everything just felt better quality. Great active circuit and the passive tone control that worked at the same time was really nice. Mine was pretty light...
Unbolt the string at the headstock, make sure the tailpiece end is wound in as far as it will go (so you can then wind out for tension), grab the cut end of the string with some small pliers, pull to tension and rebolt?