Wavelength determines fidelity. For high, surface detail you need high frequency, while for lower, but deeper detail you need low frequencies.
Infrasound frequencies travel further, and so can be used as a long distance communication channel without any need for electromagnetic radiation. Low frequencies produce fewer reflections. They are great for seeing through walls, not so good for seeing in the dark. Being infrasound they cannot be heard without assistance. Like elephants. Elephants have a better ability to hear infrasound than humans.
Ultrasound frequencies travel less far, but have very high fidelity, and produce more reflections. They are great for seeing in the dark and around walls, but not so good for 'seeing' through walls. Being ultrasound they cannot be heard without assistance. Like dogs. Dogs have a better ability to hear high frequencies than humans.
Both are great. Because echolocation is main,y concerned with not bumping into things, high frequencies - and ultrasound - are more commonly found in nature. But elephants (and possibly whales) have the ability to use infrasound for long distance 'phone calls'.
Without mechanical assistance it may be really hard to achieve either ultrasound or infrasound frequencies - hence why palatial clicks (high frequency) or cane taps are most used. A portable infrasound generator would be the equivalent of a subwoofer. But an electronic cane that you could press hard against the floor could provide great infrasound frequencies.
So a double action comms. cane with an ultrasound chirp and an infrasound tip could really work. You would need earbuds to decode the information, but it would be effectively silent.
Being able to generate two frequencies from each hand would provide a far easier access to 3D resolution. Even though your ears will provide excellent 3D awareness, the brain can use whatever it's given, and two precisely known sources provides a clearer image.
So, you want the body to produce it.. Maybe there's a way of training yourself to generate and sense infrasound, or even ultrasound. You may need a prosthesis such as a special tooth to pick up ultrasound. Infrasound can sometimes be sensed, even though it cannot be heard.