There a few major differences between a two-channel and a one-and-a-half-channel audiometer. Most of us have experience using a two-channel audiometer like the AudioStar Pro™ (or the GSI 61™) with mirror controls for channel one and channel two. With a two-channel audiometer, you are able to use channel one to conduct speech audiometry, while you have tone stimulus routed through channel two. It is also possible to route stimuli from both channels into the same ear for seamless pediatric testing. Both channels have the ability to present and route stimuli to any ear and transducer that is available. Two-channel audiometers are considered type one audiometers and are the industry standard for clinical testing and research.
With its full routing flexibility, array of sound field options and multiple transducer capabilities, the AudioStar Pro is the answer for complete clinical testing of all age ranges. Typical practice/test types include hospitals, the VA, those that conduct pediatric and CAPD testing, universities and research facilities, cochlear implant centers and private practices.
Pello™, GSI’s one-and-a-half channel audiometer, is considered a type two audiometer. With Pello, channel one becomes the primary stimulus channel and channel two is dedicated as the masking channel. Channel two routing will always be opposite to channel one, with a few very specific exceptions. Those exceptions include the Stenger test, and dichotic tests (numbers, words, sentences) found on internal word play lists or external media devices such as CDs.
Pello is an adaptable audiometer with 4 different license options to consider. The standard license allows for standard audiometric testing (air, bone, and speech). A license for additional speech testing capabilities, including the Quick SIN and BKB SIN, is available with “Speech Plus.” Automatic scoring features are also available with this license. Fine frequency testing is available out to 20kHz with the “High Frequency” License, and the TEN test, pediatric noise and classic auditory tests (ABLB, SISI, tone decay) are included with the Special Tests License. Licenses can be selected based on current needs, and additional licenses may be added in the future should your testing protocols change.
Pello has a significantly smaller footprint than the Audiostar Pro, and easier portability. It is geared more for testing adult populations, and will typically be used in satellite clinics or private practices with emphasis on dispensing amplification. For audiologists who test Pediatric populations, Cochlear Implant patients, and CAPD, the AudioStar Pro would be the preferred option over the Pello.
Both of these audiometers are designed smart and built strong. A complete comparison chart is available here.