| Business | Phone |
| Bang & Olufsen 10300 Little Patuxent Pkwy, Columbia 21044 | (410) 740-2699 |
| Bose Corp 10300 Little Patuxent Pkwy, Columbia 21044 | (410) 884-8525 |
| Gramophone 8880 Mcgaw Rd, Columbia 21045 | (410) 381-2100 |
| Tweeter 6455 Dobbin Rd, Columbia 21045 | (410) 997-8338 |