All the styles above of the Unitron North 500 contain the same technological features just wrapped up in different packages to suit your level of hearing loss, lifestyle and personal preference. The 500 version is the budget model providing good manual hearing in noise with all the standard benefits of the North processing and Stride. It has 6 frequency channels which is 14 less than the flagship Unitron North Pro and Unitron North 800 but still a decent number for hearing technology at this price.
Sound Nav in the Unitron North 500 model identifies and classifies quiet and noise environments and uses AutoMic to change from listening to everything to only listening to what's in front to improve listening comfort. This is 3 less than the Unitron North 700 and the Unitron North 600 would automatically reduce background noise as well as use directionality to improve hearing in noise.
Sound Conductor is in all Unitron North Hearing Aids but uses the additional information from SoundNav (Pro, 800, 700, 600, & 500) and SpeechZone (Pro & 800 only) to dynamically balance the appropriate features providing speech understanding and comfort while maintaining natural sound quality.
Also worth noting, at the time of writing, all Unitron North Hearing Aids have a 101dB dynamic range which is the best in the industry. It basically means there is less distortion so even sounds like music remain pure and clear.
In The Hearing Lab's opinion, the Unitron North 500 is a good manual aid. If you don't like 'fiddling with buttons then the Unitron North 600 would be a better investment. If you find yourself in varying levels of background noise, it's definitely worth paying for the upgrade to the Unitron North 700 for the extra 3 environment classifiers in the SoundNav feature.