Just an additional review. I’ve owned both the Orions and LX521’s. The LX521’s were way better to my ears. I started with the passive mid-tweeter crossover ASP.3, then tried miniDSP, then built the ASP.4 with through hole components finally returning to the ASP.3. I know some will think it’s crazy but MiniDSP definitely wasn’t for me and the ASP.4 just didn’t image as well in my setup(I’m definitely in minority here I know)??? I got into building class A amps and made the mistake of selling the LX521’s and building some high efficiency speakers. I quickly realized I should have stayed married to the LX521’s and am now making investments to reinstate our relationship. I’ve purchased a Zapco HDSP with much better DAC capabilities so will revisit DSP. If not I always have the trusty ASP.3 that did not go with the sale

. Long story short but nothing I’ve heard at Rocky Mountain Audio Fest or Axpona holds a candle in my opinion. The imaging is insane.
So to talk about bass and need for subs for a second. I mix live sound and generally run subs up to about 110dB at FOH with plenty of feeling in the chest. You will NOT get that out of LX521’s. However, they do have a good amount of bass for audiophile listening in the 80-90dB (say at 8 feet away) range without subs. If you high pass at 40-50hz they will play a bit louder before compressing bass. Dipole bass is very special but definitely not what you will impress your friends with as it just does not pressurize the room in the same way. I selectively ran with boxed subs depending on listening goals and genera. For example electronic music sounds fantastic but adding subs does help the experience. The Seas subs in the LX521 are very special, they have 30mm Xmax and do not bottom out as suspension catches before it hits the back plate. The Vd is something like 1000cc which is more than many 15’s and even some 18’s. In a dipole configuration with cancellation you do lose a bit of bass which this smallish sub makes up for with its extended displacement. The sub is probably the highest quality sub I’ve ever used.
Last point I’ll make is my current high efficiency speakers measure well and sound good and host a great party

. LX521’s didn’t excite many friends and family like my current monsters do simply because they can do much greater than 100dB without straining…. But when everyone goes home I no longer sit up by myself and enjoy the music as I used to

. Maybe I can talk my wife into multiple rooms of audiophile equipment….