Preoperatively , candidates will be assessed with their current amplification to evaluate their appropriateness for entrance into the study. The candidates' audiometric configuration must meet the above inclusion criteria. That is, the candidate must have a severe-to-profound sensorineural hearing loss from 250 to 8000 Hz. Prior to testing, the appropriateness of the hearing aid fitting will be assessed and adjustments made if necessary. In cases where amplification has not been used for more than one year, new hearing aids will be fit, worn for a minimum three-month trial and the participants re- evaluated to confirm continuance with the study.