OK, so first, it sounds like you are looking to do a decently high end build. What is your price point?
Instead of active, which I’ve been playing with, I’d recommend a bi-amp situation where you can amp each driver separately. That will make sense in a minute.
From there, I like the WOM160_vMS drivers in a MTM or TMM if you need more volume (like over 113dB driven), or a single one if you are looking for 105dB, give or take, when at full (at 3M around 96dB). I would match that driver with the SB-Acoustics_Satori_TW29DN-B-8_tweeter.
Click to access SB-Acoustics_Satori_TW29DN-B-8_tweeter.pdf
With that, you can cross low, while also having a woofer with extremely low distortion.
Now, with the bi-amp, you can send the signal from a DAC or a receiver to one or two miniDSP 2x4HD (about $200 a pop), which then sends onto the speakers. If doing a standard TM (only two drivers), you then only need 1 DSP. From there, you then send to two 2-channel amplifiers, a channel per driver.
In this configuration you get all the benefits of an active speaker without heat constraining your amplifier, while also doing DSP driving per channel and all the benefits that come with running that. Or you can look for buying a piecemeal adau1467, adau1466, or adau1452 off of aliexpress (but look for the number of output because you need 2-3 output per channel input to act as an active crossover while correcting the signal).
The miniDSP is just a finished product and easier and more documented. But it’s all on what you want.
That will come to around $500 for the drivers alone, the cost of any amplifier units you buy with the power supply to drive them and whatever housing you make for them, the costs of your DSP, a DAC or receiver if you don’t have one, etc.
But, at the price point, those drivers should give you amazing performance, low distortion, flat response, great off axis to between 45 and 60 degrees off axis out to 10kHz, and made to cross with a sub around 80dB with a linkwitz-riley filter on the DSP.
This is a build I’ve looked at to turn into a 5.1 system. So I can say the specs look pretty good on those. Not cheap, but I’d sell a pair of bookshelves made from this for like $2K, and they would be comparable or exceed speakers at that price point. With the electronics included, it would be closer to $3,500 if I integrated it into the speaker. For that, you just build an extra compartment onto the back, then have to mount everything to a back panel or a plate amp. You could just buy a plate amp as well, then do an external DSP before reaching the full range plate amp.
Just use your imagination. You can do some amazing things.
Edit: and you can get up to 108dB from the kartesian driver mentioned. there was a reason I chose 105dB and only 40W driven, but I forget why I did that in my modeling (plus, more likely how I would use it in my room at 10-15ft which is 96dB, so you won’t go over that as much; I think I chose that level to keep other aspects of what they posted from the klippel testing within certain parameters to keep the distortion from the transducer extra low, like under 0.1dB, meaning more than 60dB down from where the action is, which means it will sound so clean and smooth you won’t worry about anything else).
But, that goes into aspects of design, then using the DSP to create a top end compressor to prevent it ever playing above that level, so that once you turn the volume up and hit that, you can never play above the prime level of the speaker as a whole and never blow a driver.
Once again, that is the nerd in me.