Think, even if you will take LM-515CD, sound will improve significantly, comparing Oppo or some other middle class solid state CD players. It`s going much closer to analog sound, have some vibrations, deep and warm mids, which hard to find at that price range or higher enough.
At my experience with LM 219 and LM 210, replacement of 300B tubes, is not so much step ahead. I tried STC-4300, one of the best sounding tubes ever, and improvement was just for some very experienced listeners, so stock Shuguang tubes are good enough.
Very interesting story, that LM 219 actually so good in basic version, so even if you will try to find some preamp for further system upgrade, it will be not easy story. At my experience only Shindo gave some real step ahead, that can be valuable.
It looks, one of the good idea for upgrade, to make a right choice with interconnects and speaker cables.
At my experience with LM 219 and LM 210, replacement of 300B tubes, is not so much step ahead. I tried STC-4300, one of the best sounding tubes ever, and improvement was just for some very experienced listeners, so stock Shuguang tubes are good enough.
Very interesting story, that LM 219 actually so good in basic version, so even if you will try to find some preamp for further system upgrade, it will be not easy story. At my experience only Shindo gave some real step ahead, that can be valuable.
It looks, one of the good idea for upgrade, to make a right choice with interconnects and speaker cables.