Following a thorough hearing assessment, a hearing prescription and if you require In the Ear Hearing aids we take ear impression moulds. These are then sent to the hearing aid manufacturer.
Once at the manufacturer, the ear impressions are scanned by a digital 3D scanner.
This is then processed by a skilled “modeler” who designs the customer hearing aid to suit the patient’s requirements.
This model is then sent to a 3D printer who print the hearing aid shells. This is usually done with acrylic, but some are made by printing in Titanium, to make them stronger and smaller.
A technician then pumps silicone into the shell, the shell is then cracked away like an eggshell leaving the silicone ear mould.
Each hearing aid has its own unique serial number which is added using a laser.
The delicate electronics required for the order are assembled to the face plate ready for “closing”. This means the face plate with all the electronics will be mated with the shell along with received tubing and vent tubing.
The microphones, receivers, face plates and any other parts required for the order are then picked and sent to another technician who assembles the hearing aid.
The hearing aids then go through a listening check. The shells are then put through a cosmetic process – the shell gets buffed and clear lacquer is put on it.
The finished hearing aid is then checked by quality control which is a two-step process:
Step 1: Visual – Does the product look good, does the battery compartment open and shut OK etc.
Step 2: Electric acoustic testing is performed on the hearing aid to check that it is getting the right gain, the right output and the right frequency response. Once this test has been passed, the hearing is programmed with the audiogram of the patient.
The finished product is then packed, bar coded, addressed labelled and shipped.
A hearing aid takes around two days to be made from start to finish. This is because multiple hearing aids are being manufactured simultaneously. But once we factor in the design process, shipping each end and quality control we usually find this is around 5-10 working days.