Microphone Testing

Harmony BTE

Testing the Harmony Built-In Microphone:
You can test or monitor the sound produced by the built-in internal microphone of the Harmony Processor. This is useful to verify microphone function and for troubleshooting the processor components. Perform a microphone test even when the processor is new to establish a baseline to monitor the internal microphone for any sound quality changes.

You will need to use the Microphone Test Earphones that came with your processor or a mini amplified speaker (available from an electronics store) or the powered speaker of a personal computer.

Harmony BTE with Audio Interface Cable

Harmony BTE with Direct Connect Earhook and Cable

Harmony BTE with Direct Connect Earhook, Cable, and Audio Interface Cable, attached to mini amplified speaker

Procedures 

1. To assess the microphone, you will need an empty program slot on the processor. Speak with the child’s audiologist to determine which program slot is empty.
2. Connect the PowerCel™ Battery to the processor and select the designated empty program slot for Microphone Testing. The Harmony LED glows a steady Green so you can tell that you found the empty program position.
3. Connect the Direct Connect Earhook to the processor.
4. Connect the Direct Connect Cable to the earhook and connect the Microphone Test Earphones to the Direct Connect Cable.
5. Place the earphones over your ears, have someone speak normally near the Harmony Processor built-in microphone and listen closely to the sound from the processor.

Alternate Method

1. Connect the Direct Connect Earhook to the processor, then connect the Direct Connect Cable to the earhook, and finally connect the Audio Interface Cable to the Direct Connect Cable.
2. Plug the other end of the Audio Interface Cable into the port on the mini amplified speaker (top port marked: Input) or the appropriate audio input port on your personal computer.
3. Hold the processor at an arm’s length away from the speaker to prevent feedback or distortion.
4. Turn on the processor (attach battery) and select the microphone test position (the empty program position) using the program switch.
5. Starting with the volume control turned all the way down on the speaker, gradually increase the volume on the speaker while speaking normally to monitor the sound output.

Microphone testing is simple and important. It provides another useful means for parents, educators, and clinicians to ensure that young children get the most out of their cochlear implants.

Frequently Asked Questions

Q: Where is the microphone located on the Harmony Processor?
A: The microphone is located behind the earhook. However, if you are using the T-Mic, the microphone is located on the tip of the T-Mic at the entrance to the ear canal.

Q: Will a microphone test assess the headpiece cable as well?
A: No, the ear-level microphone tester only assesses the internal (built-in) microphone of the processor. Unlike the body-worn processors, in which the microphone is in the headpiece and therefore both microphone and cable are assessed. With ear-level processors, the microphone is in the processor itself located at the base of the earhook. Hence, the cable is not required to test the internal microphone.

Q: Can I test the T-Mic as well?
A: No, the ear-level microphone testers only asses the internal microphone of the processor and require the use of the Direct Connect Earhook as opposed to the T-Mic Earhook.

Q: Does the headpiece need to be on or attached to test the microphone of the processor?
A: No, the headpiece does not have to be attached or even locked to the patient to test the microphone.

Q: Do I have to have a program slot empty?
A: Yes, to test the microphone, one program slot must be empty.

Q: Is there any issue with leaving a program slot empty on the processor?
A: No, this is similar to the microphone test position on the body-worn processor.

Q: Does the audio-mixing ratio setting matter?
A: No, mixing ratio does not affect the Microphone Test. Remember, an empty slot should be used for the Mic Test position; hence no program is downloaded to the program slot that will be used for testing.

Q: What will happen if I try to test the microphone with a program slot that has a program downloaded to it?
A: If the person is wearing the processor at the time, you will not hear any sound from the microphone-testing speaker or earphones and will therefore not be able to monitor the microphone. If the person is not wearing the processor at the time, you will hear an intermittent signal from the speaker. Therefore, to properly test the internal microphone of the Harmony, you should leave one program slot empty.