Definitive Technology Demand D15 Speakers (Pair, Gloss White) Expired

Hi, the D11 uses a 6.5" mid/woofer; these use a 5.25". These would be something like the D9 stacked on top of the dual 5.25" bass woofers.
Most of the midrange roughness in the D11 is most likely from a resonance in the passive radiator.
This is probably not present in the D15 since the design is different & the woofers which drive the passive radiators do not receive frequencies high enough to excite a resonance in the midrange.
Audioholics published very detailed, well acquired, test results for this speaker, the D15. No reason to imagine what they measure like.
https://www.audioholics.com/tower...demand-d15

'upgrading' any driver in these will require reworking the crossover. That will be more important than anything else.

You would need to be able to measure very accurately in multiple ways and understand how to design a complex, driver specific, 3-way passive crossover. This is very difficult to do well even for very advanced hobbyists. Expect to spend significant time and resources and get a lot of help from the forums & books and getting lucky to have any chance of an improvement. Really not saying this in a condescending way, sure it might sound better to you if you slap a beryllium tweeter in there and call it done but yah it really won't be.

If you follow ASR you know even long standing companies like GR research, PartsExpress, and DIY groups using expensive Purifi drivers in custom designs have failed to impress more often than not. Heck loads upon loads of companies from entry to very high end price wise have struggled to pull off an objectively good design, even when factoring in for a wide subjective preference.

Honestly, instead of butchering the D15, I'd recommend you buy some sort of 'PEQ' and learn what can and can't be done tailoring the sound with that(big learning curve but worth it) and play around with it.
Also buy a simple 2-way DIY kit that sounds good but has some notable 'upgrade' paths and spend some time putting it together and then reworking the crossover and driver swapping in that to start to lean what goes into the situation. Who knows someday you may be a designer.

Also taking the 1/4" aluminum face off the D15 to get to the drivers is not for the faint of heart. It will not come off easily. I have taken one off a D9, it was a situation.

It's not found, it's a promotion exclusive to SD. Lots of Adorama posts are.

No amps on these. Passive radiators only.