Reducing power consumption in the cochlear implant is crucial to the development of future smaller sound processors. The commercial MP3000 sound coding strategy has been shown to be more efficient in power consumption to the standard ACE strategy. However in order to develop smaller sound processors, further battery life power savings are required. The aim of this study is to evaluate three experimental sets of MP3000 parameter sets, compared against the default ACE program. In the background for each of the four strategies, experimental noise reduction programs (SpatialNR and NR3) will also be in use. In an additional phase of the study, low stimulation rate ACE programs will also be evaluated against the default stimulation rate.

Inclusion Criteria:

1. Adult (>18 years) cochlear implant recipients
2. Implanted with the CI500, CI24RE and Nucleus 24 Series and CI422 cochlear implants.
3. User of commercially available Freedom, CP810 or CP900 series sound processor
4. User of the ACE strategy or MP3000 strategy
5. At least 3 months experience with the cochlear implant
6. Native speaker in the language used to assess speech perception performance
7. Willingness to participate in and to comply with all requirements of the protocol

Exclusion Criteria:

1. Additional handicaps that would prevent participation in evaluations
2. Unrealistic expectations on the part of the subject, regarding the possible benefits, risks and limitations that are inherent to the procedure and investigational device