Investigators	Student Population	Results Obtained With FM Sound Field Amplification
Crandell & Bess (1987)	20 students with normal hearing	Students showed significant improvement in sentence recognition ability under the amplified condition in typical classrooms (S/N = +6 dB, RT = 0.6 s).
Blair, Myrup, & Viehweg (1989)	10 students (CA: 7–14 yrs.) with mild-moderate SNHL	Students with mild/moderate SNHL demonstrated an average of 12% improvement in word recognition score when using personal hearing aids with FM sound field over hearing aids alone.
Jones, Berg, & Viehweg (1989)	Kindergarten students with normal hearing (n = 18) and mild hearing loss (n = 18)	Use of FM sound field amplification decreased student-teacher distance and produced word recognition scores comparable to close listening at 4 feet.
Flexer, Millin, & Brown (1990)	Primary age children with developmental disabilities	Developmentally disabled students with history of persistent conductive hearing loss exhibited improved word recognition scores.
Neuss, Blair, & Viehweg (1991)	Students with minimal hearing loss	Students with minimal hearing loss demonstrated improved word recognition scores in noise when using sound field amplification rather than personal hearing aids.
Zabel & Tabor (1993)	145 regular education 3rd–5th grade students	Students achieved improved spelling test scores under FM sound field amplification in quiet and under degraded listening at a +12 dB S/N.
Crandell (1993)	20 students with normal hearing	Significantly higher word recognition scores were achieved by students at distances of 12 and 24 feet when using sound field amplification.
Crandell (1996)	20 non-native English speaking children	Improved speech perception scores were achieved at distances of 12 and 24 feet when using sound field amplification.
Poissant, Brackett, & Maxon (1997)	10 normal hearing children using mild gain hearing aids and 10 children withl multi-channel cochlear implants	FM sound field amplification partially restored acoustical cues obliterated by distance and noise, making it easier for cochlear implant users in the mainstream to accurately perceive speech.
Smaldino, Green, & Nelson (1997)	31 normal hearing college students in a phonetics class	Significantly fewer fine auditory discrimination errors with sound field amplification at approximately +10 dB than in an unamplified condition.
Cranell, Holmes, Flexer, & Payne (1998)	8 children and 10 adults with cochlear implants	Traditionally placed sound field system did not sigificantly augment speech recognition for listeners with cochlear implants on any of four subtests of the Early Speech Perception Test Battery under any of four listening conditions.
Prendergast (1999)	101 K-2nd grade regular education students with normal hearing	Mean word recognition scores on the WIPI increased 4.12% when using sound field amplification.