Dynaudio BM15 Passive Crossover

[kidb]

Went down a rabbit hole after my trusty ole Dynaudio BM6a finally gave up. I decided to turn them into passives, which is still in progress due to some parts being not yet in stock. But it got me curious about my Dynaudio BM15s. I took a peak inside and wanted to know if upgrading them was worthwhile. So I ordered the parts built a replacement board and I'm happy with the results. I modded one and kept one stock to A/B. I feel more low end coming through in a way that makes the stock crossover sound a little lacking and a smoother high mid thing thats nice and a tad less hard sounding. Debatably smallish but good improvements. 7~10% nicer???

I'm not going to say everyone should upgrade their BM15s, but what I thought would be interesting to share is the crossover for people who own the BM15a that want to go passive before or after the amps fail. The passive crossover has decent but not high quality components in it. I've had Dynaudios for 14 years now, feels good to refresh them and keep them going. I wanna help keep these things going for people who still want to use them, and save some BM15As from the trash bin. So I've attached the BM15 crossover, and will get to the BM6A after the holidays sometime.

Cheers

 

[kags]

Great work! I've been considering that with a few of my older, dead powered speakers. Did you analyze the DSP/electronic crossover function of the active/powered version before designing the passive x-Over, or did you simply work out the passive crossover from scratch?

 

[kidb]

I dont own the active version of the BM15, just upgraded the passive crossover! I have the BM6A however and starting from scratch there. It would be fun to do some measurements and tweak of course.. wouldn't mind diving into more crossover design, as I have an old pair of KRK E8's that need repair... or a crossover!

 

[kags]

Right on.

I’ve been debating for recreating am active x-over either as active or passive whether to go from scratch or start by measuring the response of a working unit. So many powered monitors die and aren’t worth the effort to troubleshoot and repair if I can simply use off-the shelf stuff to build a similar x-over. I would prob go class D and DSP for most systems today.