Telephone communication is often of concern to employers and people who are deaf or hard of hearing. Traditionally, there are two different technologies that can be used for telephone communication, text telephone (TTY/TDD/TT) equipment and telephone amplification. It is necessary to determine if the individual with hearing loss will benefit from amplification. If not, then text telephone equipment will likely be the chosen option. TTY equipment is used when a person does not have enough functional hearing to understand speech even with amplification. Amplification allows people who are hard of hearing to benefit from enhanced volume when using the telephone. Amplification can be provided through the handset, headset, in-line amplifier, portable amplifierm or a control on a telephone base. Some assistive listening devices can be used to provide telephone amplification. Cellular telephones can also be used with amplification features and devices. In addition to amplification, the adjustment of sound frequency may help someone who is hard of hearing in using the telephone. For some people amplification is not so much the problem as is the need for clarity. Clarity can be achieved by adjusting the frequency of the incoming voice when listening on the telephone. Telephones and amplifiers are available that provide a clarity function or equalizer to adjust voice requency. The function of wearing a telephone headset to perform essential job functions can be difficult for some individuals who wear hearing aids. Often times discomfort (feedback) is reported as being a problem because the telephone headset rests on top of or near the hearing aid the person may be wearing. Individuals may also have difficulty hearing the conversation on the telephone when using a headset. There is no particular headset that is designed or marketed as being compatible with hearing aids from the perspectives of comfort or amplification. Generally, the individual may have to try a couple of different headsets or ways of wearing the headset before they become comfortable using one.