Chazz,
Musical subs are are about two things. Low Q (look for low group delay) and low distortion. Then it is only about power output - what do you need - decent LF power is very expensive.
The HT Shack subwoofer tests is a great resource. You will notice that low group delay tends to comes with a sealed box. The good ones tested are SVS PBultra sealed, JL F113 and teh Geneled 7073A. Genelec is expensive but has an impressive 5% THD at 20 HZ at 105 db SPL - given that in comparison to the JL, which has more than 20% distortion, one might conclude that the only audiophile music quality commercial sub they tested so far is the monster Genelec - at least of those they tested. The DIY TC Sounds LMS-5400 18" sealed 100L was the best oversall - I may be wrong but I think you are talking around $2000 for the driver alone and it is nolonger available to DIY'ers.
Note that low group delay seems to be important - my guess is that the REL subs despite their lousy distortion results are well liked because they have low group delay and a nice natural in room curve (rolls off at lower frequencies where room boost comes into play).
I think DSP is almost unavoidable for most rooms, unfortunately. Ideally you would like to have the perfect room with lots of acoustic treatment. I would advise to do the absolute maximum acoutic treatments you can BEFORE doing any DSP. DSP is never a good thing - so it should be used sparingly to tame extreme room modal peaks.
Your idea that small woofers are better than big woofers is not something that is supported by any test data.
Musical subs are are about two things. Low Q (look for low group delay) and low distortion. Then it is only about power output - what do you need - decent LF power is very expensive.
The HT Shack subwoofer tests is a great resource. You will notice that low group delay tends to comes with a sealed box. The good ones tested are SVS PBultra sealed, JL F113 and teh Geneled 7073A. Genelec is expensive but has an impressive 5% THD at 20 HZ at 105 db SPL - given that in comparison to the JL, which has more than 20% distortion, one might conclude that the only audiophile music quality commercial sub they tested so far is the monster Genelec - at least of those they tested. The DIY TC Sounds LMS-5400 18" sealed 100L was the best oversall - I may be wrong but I think you are talking around $2000 for the driver alone and it is nolonger available to DIY'ers.
Note that low group delay seems to be important - my guess is that the REL subs despite their lousy distortion results are well liked because they have low group delay and a nice natural in room curve (rolls off at lower frequencies where room boost comes into play).
I think DSP is almost unavoidable for most rooms, unfortunately. Ideally you would like to have the perfect room with lots of acoustic treatment. I would advise to do the absolute maximum acoutic treatments you can BEFORE doing any DSP. DSP is never a good thing - so it should be used sparingly to tame extreme room modal peaks.
Your idea that small woofers are better than big woofers is not something that is supported by any test data.