The Lombard effect refers to changes in voice level when (non-speech background) noises are present. People raise their voice level. The Fletcher effect refers to changes in voice level when own-voice level is increased or decreased. If own voice is amplified, speakers decrease voice level. Another (bit specialized) review is cited below.
Peter Howell
Howell, P. (2004). Effects of delayed auditory feedback and frequency-shifted feedback on speech control and some potentials for future development of prosthetic aids for stammering. Stammering Research, 1, 31-46.
From: AUDITORY - Research in Auditory Perception <AUDITORY@xxxxxxxxxxxxxxx> On Behalf Of Sarah Hargus Ferguson
Sent: 30 June 2019 17:49
To: AUDITORY@xxxxxxxxxxxxxxx
Subject: Re: Effect of sidetone in lowering one's own voice
The Lombard effect refers to changes in speech that occur when speech is produced in the presence of noise. Kathy Pichora-Fuller and colleagues wrote a very nice review of this literature (as well as the clear speech literature) in https://www.thieme-connect.com/products/ejournals/html/10.1055/s-0030-1252100. I’ve never heard of the Fletcher effect, and a google search of it was unhelpful, so I can’t say whether these effects are the same are not. From what I’ve seen in the Lombard literature, it’s not often clear in methods sections whether or not talkers can hear their voice via side-tone.
Sarah Hargus Ferguson, PhD, CCC-A
Associate Professor
Department of Communication Sciences and Disorders
From: AUDITORY - Research in Auditory Perception <AUDITORY@xxxxxxxxxxxxxxx> On Behalf Of D Sen
Sent: Friday, June 28, 2019 2:30 PM
To: AUDITORY@xxxxxxxxxxxxxxx
Subject: Re: [AUDITORY] Effect of sidetone in lowering one's own voice
Thanks Ole. (Also to Dhurandar and JJ who responded outside of the list).
I am interested in the Fletcher Effect and the Lombard effect. Both of those show variations in the speaker’s own voice (level, format shifts, etc) in the presence of noise or sidetone (i.e. own voice fed back into the ear usually through headphones).
Is there evidence to suggest that the Fletcher and the Lombard effect are essentially the same effect - where the perceived SNR of the ‘own voice’ is causing a level rise in the ‘own voice’?
Also, while there is evidence to suggest that ‘own voice’ is raised in the presence of noise or ‘lower feedback of the own voice through sidetone’, is there evidence of lowering the voice to below nominal/ambient levels when the sidetone is raised substantially (where in the extreme case, the speaker would be whispering when the sidetone is played back at a high enough level).
Thanks,
Deep
On Jun 27, 2019, at 5:48 AM, Ole Adrian Heggli <oleheggli@xxxxxxxxx> wrote:
Hi Deep,
That depends on whether you are asking about a relative/absolute decrease of pitch or amplitude?
Might be of interest, if it's pitch:
Dixon Ward, W., & Burns, E. M. (1975). Pitch performance in singing without auditory feedback. The Journal of the Acoustical Society of America, 58(S1), S116-S116.
Mürbe, D., Pabst, F., Hofmann, G., & Sundberg, J. (2002). Significance of auditory and kinesthetic feedback to singers' pitch control. Journal of Voice, 16(1), 44-51.
Cheers,
Ole Adrian Heggli
tor. 27. jun. 2019 kl. 06:21 skrev D Sen <dsen@xxxxxxxx>:
Are folks aware of work that studies he lowering of one’s own voice when there is feedback of their voice through side-tone (through headphones)?
Thanks,
Deep
