Does it matter if the coils are through clothing or not? Is it best to place directly on skin? @Bob thoughts?
Sure, the coils will work fine through clothing, but also in contact with the skin for most people since the gray rubber is medical-grade TPR.
There is No impact on performance of the magnetic field? Besides Omni-8, what other programs are good for back pain or locked hips?
For thin clothing: no impact
For thick layers like a parka or a pillow: magnetic field intensity will drop according to basic known physics
Other pulse protocol: individuals vary, but you could try Alpha wave, Schumann 3, 4, or 5, or basically experiment with any other pulse pattern.