"More important, IMO, is to have a SEALED sub for music."
Can anyone provide a supportable reason for this, or is this just an ad nauseum repeating of inaccurate information?
Subwoofer sound is primarly dictated by QTC and group delay. It is easier to build a sealed subwoofer with a low QTC and group delay (just throw a driver in a large sealed enclosure, the bigger the lower the QTC), but a vented subwoofer (whether ported, slot load, transmission line, or passive radiator) works just as well or better when properly designed. With decent quality subwoofers, the vast majority of issues people have are room and tuning related, not equipment related.
Just a few music focused manufactures using vented designs:
Vandersteen- Yep, slot load, including his $18,900 Sub Nine. Perhaps someone should let Richard know he isn't building his speakers correctly. After all, he is just a truck driver from Hanford, what does he know?
Wilson Audio- Yep, ported. But hey, David Wilson was just just selling speakers to deaf people.
Legacy- Passive radiators. I only heard Legacys once and was less than impressed, but it was 20 years ago and the room was less than optimal, so I really can't say they are good or bad. That said, they seem to be among the most liked brands. But again, perhaps Bill Dudleston doesnt' know what he is doing. Someone should let him know he should change his designs, as they are not audiophile approved as sealed.