I auditioned both models and found the 1530s to be boomy. This was a side by side comparison and it was with a 700 watt amp. As any well seasoned audiophile knows the room could have been the cause, but with full control of the volume I don't think it was room gain and overload. Just my opinion. Clarity of the bass was better in the 1230s. I still have a pair in the cellar. I now use the L1290/2s. There is a microscopic improvement in the upper bass on this model. I have a complete 5.4.1 system using all
L1290/2s. One thing for sure is ALL ADS speakers were and still are superb.
Thanks for your impressions. My 1230s sound boomy only when I place them too close to the wall - too close being less than a foot. Right now, I have them placed about 15" from the rear wall, which actually improves the bass from where I had them before, about 3 feet from the wall. Never heard the 1290s, which I believe uses the same drivers in a tower configuration.