The purpose of this study is to evaluate the benefit of bilateral implantation with bone-anchored hearing systems (BAHS), in terms of sound localization abilities, as well as auditory working memory. The hypothesis is that the use of two BAHS (bilateral condition) will not only improve localization abilities, but it will also increase the ability to retain words in working memory, compared to performance with only one BAHS (unilateral condition).

The patients included in this study are adult patients with a bilateral conductive or mixed hearing loss, that are already bilaterally implanted with two percutaneous bone-anchored devices (BAHS). The study consists of two visits. At visit 1, the patients are fitted unilaterally and bilaterally with the investigational device (Ponto 3 SuperPower). After fitting, the patients perform a test of spatial resolution (minimum audible angle, visit 1) and an auditory working memory test (visit 2). These two outcome measures are conducted in the laboratory using the Ponto 3 SuperPower unilaterally and bilaterally. Additionally, the patients fill in a questionnaire (SSQ12) to report perceived performance in their everyday life with their own devices. This is a post market study and all products used are CE marked and used in clinical practice worldwide.

Inclusion Criteria:

• Adult BAHS users, minimum 18 years and maximum 75 years.
• Native English speakers.
• Patients that are already bilaterally implanted.
• Patients with a bilateral conductive or mixed conductive-sensorineural hearing loss.
• Experience with bilateral Ponto of at least 6 months.
• Patients that are using both their sound processors daily.
• PTA BC (at 0.5, 1, 2, 3 kHz) on both sides lower or equal to 65 dB HL.
• If the masked BC is available on the patient's journal, the average difference in masked BC (at 0.5, 1, 2, 4 kHz) between L and R ear should be lower than 15 dB.
• If the masked BC is not available on the patient's journal, the average difference in unmasked BC (at 0.5, 1, 2, 4 kHz) between L and R ear should be lower than 15 dB.

Exclusion Criteria:

• Not deemed suited by the principal investigator.
• If the physician assesses that the patient is not fit for trial participation at any stage.
• Audiogram at 1st visit shows too large masked BC thresholds (PTA BC - at 0.5, 1, 2, 3 kHz - on either side larger than 65 dB HL).
• Audiogram at 1st visit shows asymmetric masked BC thresholds (average difference in masked BC - at 0.5, 1, 2, 4 kHz - between L and R ear larger or equal to 15 dB).

The participants are blinded to the tested condition (unilateral vs bilateral)