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Abstract Introduction NB CE-Chirp LS was developed to improve the audiogram estimation by auditory brainstem response (ABR) thresholds during audiological assessment of infants and difficult to test children. However, before we know how the stimulus behaves in several types of hearing loss, it is important we know how the stimulus behaves in normal hearing infants. Objective To describe ABR thresholds with NB CE-Chirp LS stimulus for 500, 1,000, 2,000, and 4,000 Hz, as well as the amplitude and absolute latency for ABR thresholds. Methods Auditory brainstem response thresholds were evaluated with the Eclipse EP25 system. NB CE-Chirp LS was presented using an ER-3A insert earphone. EEG filter was 30 Hz high-pass and 1,500 Hz low-pass. The ABR threshold was defined as the lowest intensity capable of clearly evoke wave V, accompanied by an absent response 5 dB below. Results Eighteen normal hearing infants were evaluated. The mean and standard deviation (SD) of the ABR threshold (dB nHL) were: 23.8 (±4.2); 14.4 (±5.7); 6.0 (±5.0); and 7.0 (±5.9). The mean and SD of the absolute latency (ms) were: 8.86 (±1.12); 9.21 (±0.95); 9.44 (±0.78); and 9.64 (±0.52). The mean amplitude (nV) and SD were: 0.123 (±0.035); 0.127 (±0.039); 0.141 (±0.052); and 0.105 (±0.028), respectively, for 500, 1,000, 2,000 and 4,000 Hz. Conclusion Auditory brainstem response threshold with NB CE-Chirp LS reaches low levels, in special for high frequencies. It provides absolute latencies similar between frequencies with robust amplitude. The results obtained brings to the examiner more confidence in the results registered. CEChirp CE Chirp (ABR children However loss 500 1000 1 000 1,000 2000 2 4000 4 4,00 EP EP2 system ER3A ERA ER 3A A earphone 3 highpass pass 1500 1,50 lowpass. lowpass pass. low-pass V below (SD nHL 238 23 8 23. ±4.2 42 (±4.2) 144 14 14. ±5.7 57 7 (±5.7) 60 6 0 6. ±5.0 50 (±5.0) 70 7. ±5.9. 59 ±5.9 . 9 (±5.9) ms (ms 886 86 8.8 ±1.12 112 12 (±1.12) 921 21 9.2 ±0.95 095 95 (±0.95) 944 44 9.4 ±0.78 078 78 (±0.78) 964 64 9.6 ±0.52. 052 ±0.52 52 (±0.52) nV (nV 0123 123 0.12 ±0.035 0035 035 (±0.035) 0127 127 ±0.039 0039 039 (±0.039) 0141 141 0.14 ±0.052 0052 (±0.052) 0105 105 0.10 ±0.028, 0028 ±0.028 , 028 (±0.028) respectively 2,00 levels registered 100 00 1,00 200 400 4,0 150 1,5 ±4. (±4.2 ±5. (±5.7 (±5.0 (±5.9 88 8. ±1.1 11 (±1.12 92 9. ±0.9 09 (±0.95 94 ±0.7 07 (±0.78 96 05 ±0.5 (±0.52 012 0.1 ±0.03 003 03 (±0.035 (±0.039 014 ±0.05 005 (±0.052 010 10 002 ±0.02 02 (±0.028 2,0 1,0 20 40 4, 15 1, ±4 (±4. ±5 (±5. ±1. (±1.1 ±0. (±0.9 (±0.7 (±0.5 01 0. ±0.0 (±0.03 (±0.05 (±0.02 2, ± (±4 (±5 ±1 (±1. ±0 (±0. (±0.0 (± (±1 (±0 (