The OHM D2 can be upgraded to the sound quality of an OHM C2 with the addition of a dome tweeter and crossover harness. The upper treble response is extended to add sheen to cymbals and metallic quality to horns. To use this kit you must first cut a hole in the front panel (a template is provided) and then install the crossover harness.

Both the C2 and the D2 can have tighter and deeper bass with the addition of a SubBass Activator (SBA) and our upgraded 10'' woofer. The SBA eliminates the drive below the speaker's natural response to reduce distortion and clean up the deep bass. This allows for lower distortion, higher output and deeper bass, plus uses a self-resetting protection circuit. The upgraded woofers have a new cone surround that is projected to last up to 30 years, while the FerroFluid cooling handles the thermo transients from CDs.

Note: Most Ohm upgrades require no specialized knowledge and are easily completed completed by any person. It takes less time to install your own upgrade than it does to package and return ship your speakers to the factory, therefore, we recommend you save time and money by doing this yourself. We ship the upgrade to your door with clear, easy instructions. If for any reason you prefer to have the factory complete your upgrade installation, we will be happy to do this for free, however, you will be responsible for shipping and handling costs each way.

Ohm allows up to $595 for the return of a complete pair of undamaged Ohm D2s toward 25% of the purchase price of new Ohm speakers.