Excessive cone excursion at low frequencies

[ICG]

This would only ensure the 60Hz cutoff if the speaker is coupled to a phone/tablet that has the app and is set up properly, right? If so, it's unpractical, since if someone else besides me couples their device, the speakers lose their protection, so to speak. Although it is the easiest, and lowest-power option, I'm afraid it's not the way to go for this application.

You didn't say it's an 'free for all, everyone takes his turn' kind of use. Yes, that would exactly be the case. But if someone else gets their dirty fingers on it, what would prevent them to yank everything below 60Hz by 20dB or more? Unless you prevent that also, it isn't safe either.

Makes sense, but I only need it to do this one thing. I'm not too familiar with DSP's or the like, but it seems to me they're far more complex, and therefore draw much more power than an active crossover. Is this right? I'm thinking about making the speaker portable, so keeping power consumption low would be preferrable.

No, that's not right. It's about the same in current but you typically need +/-12V for an active crossover. The Sure DSP just needs 5V DC, it got a standard micro USB plug. Active XO can be realized with other voltages too and you could also use a buck converter etc, but don't expect any power saving from being active vs. dsp. What amp do you want to use? Sure/Wondom got amps with built in DSPs.

If you want to go portal, you probably might want to use a different driver with 4 Ohm because you'll get more power out of the amp and/or can keep the needed voltage for the same power lower. If you want to use it outside, I would advise against going for 60Hz from a 3" driver, you don't have any roomgain and won't hear much of the 60Hz and the huge excursion needed will cost you a lot of loudness. The driver got only 2,5mm Xmax anyway.

Will I need a pre-amp? If no, does this mean I'll just insert the filter in-line (between the bluetooth receiver and the amplifier)?

That depends on your amp. Most class D amplifier boards available don't need a preamp, they got enough gain (most 20dB+). If you go active, you can implement a preamp easily but on bluetooth you probably want to use the volume control of the BT source anyway.

 

[AllenB]

keeping power consumption low would be preferrable.

Maybe..
Use a closed box.
Turn down bass control, the low end is affected most.
Passive filter in the amp.
Passive filter on the speaker.