Class D output filter: ferrite bead vs. LC filter

Hey out there,

So I recently put together my first class D amplifier built around the TPA3110D2 chip from Texas Instruments. Schematic here. To my dismay, when I first fired it up, it would only work at very low volumes. When the volume to the inputs was increased to normal listening levels, the amp kept going into over-current shutdown mode. After conversing with TI engineer, it was decided that the ferrite beads that I was using for output filters were saturating at the current I was trying to drive the speakers at and causing a short through the 1000pF caps that sat between the speakers outs and ground. The solution? Remove the caps, so I did (C18,19,20 & 21 gone now), and everything seems peachy. What I'm curious about now is am I missing something by not having a proper output filter on my amp? Would it sound better with a more traditional LC output filter? Would it sound any different with no filters at all? Are these output filters only in place to mitigate EMI and the like?

I supposed my question boils down to this: is it worth my time to build a redundant amp with proper LC filters and do a side by side sound comparison?

Here's a little more info on this particular setup:

Power Supply: 14.4V NiMH battery pack
Amp: TPA3110D2 15-W Filter-Free Stereo Class-D Audio Power Amp
Speakers: 2X 4Ohm 100W rated power, 4 inch.

Thanks again!
-Chad

The amp uses the inductance of the speaker as a filter. Since that's apparently sufficient, I don't think an external filter will improve the sound.

You can do a rough check of the speaker's filtering ability by measuring the supply current under no-signal conditions both with and without the speaker connected. If it doesn't change much, then the speaker inductance is adequate as a filter.