I honestly didn't have the first one long enough to remember much other than that it was pretty comparable to my L-2000 with the bridge pickup only and the treble boost on, but maybe even a little brighter.
The full story is that I bought the first one online, and when I got it, I was perplexed by the pickup placement. I contacted G&L about it, told them I bought a L-1500 used but the pickup wasn't in the right location and I was disappointed that I didn't get what I was expecting. They asked me to send some pictures, we had a little discussion about it, and we agreed on a course of action to replace the body with everything else transferred over. So I sent them the bass, and about 6 months later, I got the second one from the factory, which was a new body and neck (because of the transition from 3-bolt to 6-bolt) with the original bass' hardware and electronics. They kept the original neck and body. Not sure if it went in the scrap pile or is still kicking around the factory somewhere. Anyway, when they sent the new one back, I did get a message from them apologizing for the confusion, but noting that while they had my bass, they went back through their records to see if they could figure out why one would have been made this way, and found that the original plan for the L-1500 was to use the L-2000 bridge pickup location and that they did produce a small batch with this location before deciding to revert to the Climax location. At least that's what they told me. I thought it was kind of odd that they didn't know this when I had originally contacted them.