To Low Pass Or Not To Lowpass...That Is The Question

[CarlosT]

I bought some full-range Audax 5.25" drivers and the tweeter already has a high pass cap. The vendor recommended that I leave things alone since the woofer would "naturally roll off" and would not need a low pass filter. Does this sound right? Would the woofer not waste energy and sound muddied "naturally rolling off" without a lowpass filter? Sounds simple enough for a little driver.

Here are the specs

http://www.madisound.com/pdf/audax/vp130g2.pdf

 

[lndm]

To a degree, the tweeter would physically act as a mechanical crossover for the woofer, but I tend to agree with you and suspect there are improvements to be had. Looking at the response, I can see that the tweeter may be playing a little loud, and there is the dip at 1k3 to consider.

This dip could be connected with the physical displacement of the woofer and tweeter and perhaps this is the limiting factor of this unit. For this reason it may not be worth going all out unless you have the reason to measure and re-engineer the crossover.

I would probably experiment with the tweeter capacitor value, try woofer inductors, and replace the tweeter cap with a good type. I would also consider padding (L-pad) the tweeter. Possibly look at 2nd order, not sure. I'd probably put some felt damping on the back of the tweeter.

Dealing with the baffle step is another thing. If I had to do this I would rather work the woofer separately and just pad the tweeter to match. Otherwise the overall impedance would need to be compensated first.

 

[CarlosT]

Thanks. The main problem is that the tweeter crossover cap is embedded physically in the driver and I cannot see a way to get to it.