Nautilus Tweeter punched in by my 3 year old!!

[ssabripo]

well jesus A christ, I swear i'm gonna WHOOOP my kids buttocks! :M :M

my 3 year old just poked the Nautilus tweeter on my HTM1 center!! it's all crapped in and wrinkled, etc. Sound wise it doesn't seem distorted but I haven't tested it long!

I suppose a call to BMW parts is coming....does anyone know the ballpark figure on how much they go for? :cry:

[ShadowZA]

Hang in there, man.

Happened to me too some years back. These things happen. Part of life's toughness. Best is not to make too much of a fuss. Your 3 year old will have to deal with similar mishaps when he/she grows up. Lots o' strength. Wish I could help regarding cost of repair but I don't know ... sorry.

[ssabripo]

yeah, I'm a little calmer now. But still, looking at it I just cringe!

hoping someone will chime in and give me a heads up ballpark, before I have a shocking heart attack on monday when I call B&W

[wettou]

well jesus A christ, I swear i'm gonna WHOOOP my kids buttocks! :M :M my 3 year old just poked the Nautilus tweeter on my HTM1 center!! it's all crapped in and wrinkled, etc. Sound wise it doesn't seem distorted but I haven't tested it long! I suppose a call to BMW parts is coming....does anyone know the ballpark figure on how much they go for? :cry:

Happened to me as well, no big deal, Kids are more important than stuff.

The Diamond tweeter ($1000)

The regular aluminum tweeter cost me $150 to replace it

[William]

Hate to say it but if its in the reach of a 2 to 3 year old it's 100% fair game and not their fault. If your child DIDN'T try and touch, poke and explore then you would have REAL problems.

[ssabripo]

The regular aluminum tweeter cost me $150 to replace it

NICE! I can deal with $150....i cannot deal with $500-$1000


you are refering to this, I assume:

[ssabripo]

Hate to say it but if its in the reach of a 2 to 3 year old it's 100% fair game and not their fault. If your child DIDN'T try and touch, poke and explore then you would have REAL problems.

I have them "trained" well, or so I thought....from an early age, i taught my 5 year old not to touch dads equipment. I guess my 3 year old got a little bold with me being outside working on the car!

oh well. point taken......but it still is maddening!

[Lex]

The bottom line, kids will be kids. You must keep up your valuables from them, that unfortunately includes speakers. Floor standers, not a good idea with toddlers unless the covers well protect everything. Even then, well...

Sorry about your center speaker, I know it's sickening. :-(

[DM3000 Owner]

In my aptly named thread, "How t replace a tweeter in a Signature or Nautilus Speaker" you my find your answer:

http://htguide.com/forum/showthread.php4?t=30813&highlight=tweeter

Tweeter is about $160 with shipping.

[ssabripo]

In my aptly named thread, "How t replace a tweeter in a Signature or Nautilus Speaker" you my find your answer:

http://htguide.com/forum/showthread.php4?t=30813&highlight=tweeter

Tweeter is about $160 with shipping.

thank you good sir!

you are a fine gentleman and a scholar!

[Dmantis]

I know all about the tweeter push in trick with kids. Both my kids done it to my speakers years ago and i had to get new tweeters. It sucks but as said , kids will be kids.

[Kal Rubinson]

well jesus A christ, I swear i'm gonna WHOOOP my kids buttocks! :M :M

my 3 year old just poked the Nautilus tweeter on my HTM1 center!! it's all crapped in and wrinkled, etc. Sound wise it doesn't seem distorted but I haven't tested it long!

I suppose a call to BMW parts is coming....does anyone know the ballpark figure on how much they go for? :cry:

My condolences but don't you use the magnetically-attached protective screens? At least, when you are not in the room?

Kal

[ssabripo]

My condolences but don't you use the magnetically-attached protective screens? At least, when you are not in the room?

Kal

ha! kids nowdays will get around anything.....

[Race Car Driver]

The tweeter isnt bad, Ive ordered two of them from B&W replacement parts. Cost was $99 each. Sorry to hear. You could probably push it back to "close" and sell the damaged on on ebay. I see people pay $50+ for damaged ones allt he time. 8O

One of the reasons I am not jumping at the gun to get Diamonds...

[Kal Rubinson]

ha! kids nowdays will get around anything.....

Really? My last incident (about 18years ago) was when my granddaughter rode her tricycle directly into one of my Apogee Duettas. Both survived.

Kal

[dknightd]

Think of it as a learning experience for you and the child.
Likely your 3 yr old can sense they did something bad. Talk to them gently.
You could whip their butt, but I'd wait till the the third offense.
Really a gentle talking to, in a stern voice, can be very effective.
My kids would rather cut off a finger than mess with dad's
stereo, and they are only on their first warning.
Now they are older they know how to use it, but will ask first if
I'm in the house.They also know to tell me if the music is
bothering them.

Speakers can be repaired or replaced. Kids not so easy.

Sometimes I wonder. You read a lot about young children poking tweeters.
Maybe there is something about the sound they make that they do not like,
but we can't hear.

Once one of my kids decided she wanted to hear music. Apparently she
pushed the buttons on cd player etc and got no response, So then she dropped
the tone arm down on the matt - can you say goodbye cartridge. I'd told
once before not to touch dads stuff, but she was young and likely did not
understand. When she saw my reaction she understood. And so did her
siblings. Kids know when they have done bad, and most try to avoid doing it again.
I set up my kids with something to listen to music on as soon as they show an interest.

Now if they want to listen to my system they ask. One day they might decide
to do something stupid when I'm not around. That will be warning number two.
I hope that day never comes.

[ssabripo]

thanks for the words of encouragement fellas! I'm gonna call B&W and see what the wait time is.

[ssabripo]

Really? My last incident (about 18years ago) was when my granddaughter rode her tricycle directly into one of my Apogee Duettas. Both survived.

Kal

the funny part is that not only was this NOT my 3year old who did it, but my 5 year old and he blamed it on the little one!!! 8O :M

so yesterday, I started thinking, how does the little know to take the magnet off, so I called him to ask him how he did it.....and for the life of him he explained 20 different ways but none seem to be the taking the magnet protector off!

hmmmm..... so I called the older one, who NEVER touches my stuff, and asked him if he had done it since there was no way the little one did it. After some denial, he finally broke down and said " well, I kinda didn't remember that i did it...." :lol:

mystery solved

[wettou]

You read a lot about young children poking tweeters.
Maybe there is something about the sound they make that they do not like,
but we can't hear.

Kids can hear stuff we cannot especially higher frequencies, there ears are a lot more sensitive


Research paper

The development of the perceptual organization of sound by frequency separation in 5–11-year-old children

E. Sussmana, b, R. Wongb, J. Horváthc, I. Winklerc, d and W. Wange

aDepartment of Neuroscience, Albert Einstein College of Medicine, Kennedy Center, Room 925, 1410 Pelham Parkway South, Bronx, NY 10461, USA

bDepartment of Otorhinolaryngology -- Head and Neck Surgery, Albert Einstein College of Medicine, Kennedy Center, Room 925, 1410 Pelham Parkway South, Bronx, NY 10461, USA

cInstitute for Psychology, Hungarian Academy of Sciences, Budapest, Hungary

dCognitive Brain Research Unit, Helsinki University, Helsinki, Finland


eDepartment of Speech and Hearing Sciences, Graduate Center of the City University of New York, NY, USA

Available online 20 January 2007.
Abstract

The analysis of the auditory scene begins from the moment we hear sounds, making it possible for the infant to distinguish the mother’s voice from other sounds in the environment. The purpose of the study was to determine, in two experiments, whether the frequency separation threshold, at which the perception of a mixture of sounds turns from being perceived as one stream to two streams, differs between two groups of school-aged children (ages 5–8 and 9–11 years) and adults. The results show a developmental course for the perception of auditory streams that is not simply dependent upon frequency discrimination. This suggests that maturation of the stream segregation process follows a longer developmental course than maturation of simple feature discrimination. The data indicate that the ability to hear distinct sound streams in the environment takes time to develop and becomes sharpened with experience and maturity.



What Do Children Hear?

How Auditory Maturation Affects Speech Perception
see also: References

Werner, L. (2007, March 27). What do children hear: How auditory maturation affects speech perception. The ASHA Leader, 12(4), 6-7, 32-33.
by Lynne Werner

Auditory development is a prolonged process, despite the precocious development of the inner ear. Audiologists know that infants don't respond to sound at the low intensities to which adults will respond. What hearing scientists have learned in 25 years of studying the development of hearing in infants and children is that youngsters' immature thresholds in the sound booth reflect immature hearing, not just immature responses. These immaturities limit infants' ability not only to detect a tone, but also to hear and to learn from sound in real environments. Moreover, the process of auditory development continues well into the school years, as children become more selective and more flexible in the way that they process sound.

Clinicians implicitly understand that infants and children hear differently from adults, and this understanding shapes their interactions with infants and children. Research in auditory development has broader implications for clinical and educational practice—as well as public policy—as professionals work to reduce noise levels in homes and in schools and raise awareness of the effect of competing sound on infants' and children's ability to process speech.

Auditory Development

Auditory development progresses through three stages. During the first stage, the ability of the auditory system to encode sound precisely becomes mature. This stage lasts from full-term birth to about 6 months of age, and involves maturation of the middle ear and of the brainstem auditory pathways. During the second stage, from 6 months to about 5 years of age, the ability to focus on or select one feature of sound matures. During the third stage, from 6 years into adolescence, the ability to use different sound features flexibly under changing listening conditions matures. Both the second and third stages involve maturation of auditory cortex and central processing.

Stage 1: Maturation of Sound Coding

Newborns' impressive ability to discriminate between speech sounds, to recognize voices, and even to recognize their native speech has been well- documented. Clearly, infants come into postnatal life ready to listen to sound and to learn from it. This process likely begins before birth. However, studies that have tested newborns' discrimination of changes in the details of speech suggest that their representations of sound are coarser than adults' in some ways. For example, they are more likely to notice a change in a syllable if the vowel changes rather than a consonant (Bertoncini, Bijeljac-Babic, Jusczyk, Kennedy, & Mehler, 1988).

From examining very basic auditory abilities, researchers know that young infants' thresholds for detecting sound are higher than adults' and that their ability to separate or discriminate sounds of different frequencies is immature, particularly at frequencies above 3000 Hz than at lower frequencies (e.g., Olsho, Koch, Carter, Halpin, & Spetner, 1988; Olsho, Koch, & Halpin, 1987). Studies of the acoustical response of the ear of young infants point to the middle ear as a source of immature thresholds in quiet. The middle ear of an infant is less efficient than that of an adult in transmitting sound to the inner ear (Keefe, Bulen, Arehart, & Burns, 1993). The efficiency of high-frequency sound transmission through the middle ear improves considerably in the first year of life, with smaller progressive improvements across the frequency range of hearing continuing well into childhood (Okabe, Tanaka, Hamada, Miura, & Funai, 1988).

Interestingly, the inner ear seems to be mature in newborns. Nonetheless, electrophysiological measures show a broader neural response to high-frequency sounds, matching the results of behavioral studies of infants (e.g., Abdala & Folsom, 1995). Furthermore, transmission time of the neural response through the brainstem auditory pathway is correlated with young infants' ability to detect a high-frequency sound (Werner, Folsom, & Mancl, 1994).

Limitations in basic auditory abilities would be expected to limit the precision with which a young infant can represent a complex sound, such as speech. Researchers speculate that one reason adults speak slowly, more clearly, and at a higher intensity to infants is to compensate for infants' immature hearing.

Stage 2: Maturation of Selective Listening and Discovering New Details in Sound

By the time an infant is 6 months old, middle ear efficiency has improved and the transmission of information through the brainstem seems mature. However, behavioral tests of hearing still find higher response thresholds, in quiet and in noise, for infants at this age—and in fact, for children up to 4 years old (e.g., Schneider & Trehub, 1992). A small part of this immature sound detection can be due to simple inattentiveness, or infants' not being on task at all times during the test. However, most of the difference seems to result from the way infants listen to sound.

While an adult will focus on the frequencies in a sound that are expected to allow them to identify the sound, infants tend to listen in a broadband way. They listen to all frequencies rather than selecting the most informative. This difference is demonstrated in a simple task in which infants and adults learn to respond to a tone in noise (Bargones & Werner, 1994). On a large majority of the trials, the tone is presented at one "expected" frequency, but on some trials, a tone at a different, "unexpected" frequency is presented. Adults tend not to hear the unexpected frequencies, while infants detect the expected and unexpected frequencies equally well. The interpretation of this result is that infants listened for a broad range of frequencies, while adults listened only to the frequency at which they expected the signal to be presented.

Could it be that infants just don't form expectations about sound as adults do? Infants' performance in other tasks suggests that they not only form expectations but also direct their attention to increase their sensitivity to sound under some conditions. For example, if a short burst of noise is presented to cue the listener that the target sound is about to occur, both infants and adults could detect the target sound better when it occurred at the expected time, rather than at a slightly earlier- or later-than-expected time (Parrish & Werner, 2004). This finding suggests that the infants learned that the sound they were supposed to detect usually occurred at a specific time and that they listened for the sound at that time but not at other times. This conclusion means that infants have the capacity to listen selectively under certain conditions.

If infants can direct their attention to a particular time, why don't they direct their attention to a particular frequency? Researchers speculate that it is maladaptive for infants to listen selectively to a sound like speech, in which the important frequencies change depending on the speaker, the context, the language, and other factors. It may be more sensible for infants to continue to listen broadly to speech until considerable listening experience in many situations allows them to learn where the important speech cues occur. In fact, research suggests that adults learning a second language have difficulty in part because they listen to the aspects of speech they have learned to listen to in their native language, while ignoring cues in other frequency ranges that are important for the second language (e.g., Best, McRoberts, & Sithole, 1988).

One result of infants' broadband listening is that it makes it difficult for them to separate target sounds from competing sounds. Adults can have problems separating a target from competing sounds when the competing sounds change over time, and infants also have special difficulties when the competing sounds vary. For infants, though, just having a competing sound in the background seems to make it difficult for them to hear a target. For example, the presence of a competing sound, even one that is far from the target sound in frequency, increases infants' threshold for the target sound (L. J. Leibold & Werner, 2006). This susceptibility to interference from competing sounds appears to continue until children are 4 or 5 years old (L. Leibold & Neff, in press). This finding implies that learning about sound will be more difficult for infants and preschool children in noisy environments and those in which there are several competing sources of sound. Research underway in several laboratories is attempting to determine whether infants and children are able to use some of the strategies that adults use to separate target and competing sounds.

The development of selective listening involves not only picking out one sound among several, but also listening to the details in complex sounds such as speech. In a series of studies, Nittrouer (2006) has shown that young children tend to make decisions about the identity of a syllable or a word on the basis of global acoustic differences rather than on fine acoustic details. Nittrouer's findings are consistent with the idea that children do not focus in on specific frequencies. Apparently, it is only with years of exposure under a variety of conditions that children notice the details in speech.

Stage 3: Maturation of Perceptual Flexibility

By school age, children appear to have mastered selective listening: they are no longer as influenced by background sounds as younger children and they appear to focus on informative aspects of sound. School-aged children are still less consistent than adults in the way they categorize speech sounds, and researchers can still identify listening conditions that are more difficult for school-aged children than for adults.

Children are less consistent than adults in identifying speech sounds because once they have discovered the multiple redundant acoustic differences between sounds, they have trouble when all of those differences are not available to them. For example, Hazan and Barrett (2000) found that when they synthetically altered syllables so that they are distinguished by only one acoustic cue, 6-year-old children were much less consistent in identifying the syllables than when multiple acoustic cues were available. Older children and adults were as consistent at categorizing the syllables with one cue as with multiple cues. Similarly, in the presence of noise or reverberation, some speech cues may be difficult to hear because of masking or distortion, while others remain usable. Under such conditions, adults can switch to the more reliable cue, while children apparently cannot.

Finally, speech perception may be a relatively automatic process for young adults, based on years of practice. For school-aged children, however, perceiving speech in difficult listening situations may be less automatic, requiring greater attention and allocation of more processing resources. Any additional demands on attention may be impossible for children to manage. Wightman and Kistler (2005) showed recently that adults could separate two voices presented to one ear; their ability to do so was little affected by yet another voice presented to the opposite ear. Children ages 6-9, in contrast, could separate the two voices in one ear fairly well, but their performance deteriorated markedly when another voice was added to the opposite ear. One explanation of this result is that the adults could separate the original two voices because they had sufficient processing resources to block out the voice in the opposite ear, while the children required so much effort to separate the original two voices that they had no processing resources available to block out the third voice.

Implications of Auditory Development

Developmental studies of infants and young children are beginning to explain why difficult listening conditions are nearly always more challenging for children than for adults. Early in infancy, fundamental auditory processes limit infants' ability to represent the fine acoustic details in the sounds they hear. However, even after the auditory system is able to represent those details, infants and preschool children do not appear to use all the details available to them. It is as if the system remains unselective during this stage of development, so that children will learn to use the appropriate acoustic information even though the frequencies at which it will occur are uncertain. Finally, school-aged children seem to have the acoustic details available to them, and they are able to attend to those details. Auditory development in this final stage involves learning to use different details flexibly with changes in listening conditions and acquiring the practice needed to make speech perception an automatic process.

The results of these studies have implications in many realms. For the audiologist, they suggest that infants and children with hearing impairment need to hear the broadest possible range of frequencies to learn how to understand speech most effectively. For the speech-language pathologist, they suggest that children may not always hear all of the acoustic details in speech, even when those details are available to them. For those charged with designing the environments in which infants and children live and learn, they underscore the importance of reducing the levels of noise and reverberation to optimize auditory learning.

[Thea-masta]

This may sound a bit silly too you but i did this and it worked great...(not on the nautilus's though) just get a hoover and gentle suck it back out into shape. works for me and go back to original shape...works best if you have adjustable power on your hoover

[DM3000 Owner]

This may sound a bit silly too you but i did this and it worked great...(not on the nautilus's though) just get a hoover and gentle suck it back out into shape. works for me and go back to original shape...works best if you have adjustable power on your hoover

You can put a q tip or other eraser or other soft object through the back of the tweeter and pop the dome back. But it will be wrinkled. Ever try to unwrinkle a piece of foil?

[audioqueso]

Kids can hear stuff we cannot especially higher frequencies, there ears are a lot more sensitive


Research paper

The development of the perceptual organization of sound by frequency separation in 5–11-year-old children

E. Sussmana, b, R. Wongb, J. Horváthc, I. Winklerc, d and W. Wange

aDepartment of Neuroscience, Albert Einstein College of Medicine, Kennedy Center, Room 925, 1410 Pelham Parkway South, Bronx, NY 10461, USA

bDepartment of Otorhinolaryngology -- Head and Neck Surgery, Albert Einstein College of Medicine, Kennedy Center, Room 925, 1410 Pelham Parkway South, Bronx, NY 10461, USA

cInstitute for Psychology, Hungarian Academy of Sciences, Budapest, Hungary

dCognitive Brain Research Unit, Helsinki University, Helsinki, Finland


eDepartment of Speech and Hearing Sciences, Graduate Center of the City University of New York, NY, USA

Available online 20 January 2007.
Abstract

The analysis of the auditory scene begins from the moment we hear sounds, making it possible for the infant to distinguish the mother’s voice from other sounds in the environment. The purpose of the study was to determine, in two experiments, whether the frequency separation threshold, at which the perception of a mixture of sounds turns from being perceived as one stream to two streams, differs between two groups of school-aged children (ages 5–8 and 9–11 years) and adults. The results show a developmental course for the perception of auditory streams that is not simply dependent upon frequency discrimination. This suggests that maturation of the stream segregation process follows a longer developmental course than maturation of simple feature discrimination. The data indicate that the ability to hear distinct sound streams in the environment takes time to develop and becomes sharpened with experience and maturity.



What Do Children Hear?

How Auditory Maturation Affects Speech Perception
see also: References

Werner, L. (2007, March 27). What do children hear: How auditory maturation affects speech perception. The ASHA Leader, 12(4), 6-7, 32-33.
by Lynne Werner

Auditory development is a prolonged process, despite the precocious development of the inner ear. Audiologists know that infants don't respond to sound at the low intensities to which adults will respond. What hearing scientists have learned in 25 years of studying the development of hearing in infants and children is that youngsters' immature thresholds in the sound booth reflect immature hearing, not just immature responses. These immaturities limit infants' ability not only to detect a tone, but also to hear and to learn from sound in real environments. Moreover, the process of auditory development continues well into the school years, as children become more selective and more flexible in the way that they process sound.

Clinicians implicitly understand that infants and children hear differently from adults, and this understanding shapes their interactions with infants and children. Research in auditory development has broader implications for clinical and educational practice—as well as public policy—as professionals work to reduce noise levels in homes and in schools and raise awareness of the effect of competing sound on infants' and children's ability to process speech.

Auditory Development

Auditory development progresses through three stages. During the first stage, the ability of the auditory system to encode sound precisely becomes mature. This stage lasts from full-term birth to about 6 months of age, and involves maturation of the middle ear and of the brainstem auditory pathways. During the second stage, from 6 months to about 5 years of age, the ability to focus on or select one feature of sound matures. During the third stage, from 6 years into adolescence, the ability to use different sound features flexibly under changing listening conditions matures. Both the second and third stages involve maturation of auditory cortex and central processing.

Stage 1: Maturation of Sound Coding

Newborns' impressive ability to discriminate between speech sounds, to recognize voices, and even to recognize their native speech has been well- documented. Clearly, infants come into postnatal life ready to listen to sound and to learn from it. This process likely begins before birth. However, studies that have tested newborns' discrimination of changes in the details of speech suggest that their representations of sound are coarser than adults' in some ways. For example, they are more likely to notice a change in a syllable if the vowel changes rather than a consonant (Bertoncini, Bijeljac-Babic, Jusczyk, Kennedy, & Mehler, 1988).

From examining very basic auditory abilities, researchers know that young infants' thresholds for detecting sound are higher than adults' and that their ability to separate or discriminate sounds of different frequencies is immature, particularly at frequencies above 3000 Hz than at lower frequencies (e.g., Olsho, Koch, Carter, Halpin, & Spetner, 1988; Olsho, Koch, & Halpin, 1987). Studies of the acoustical response of the ear of young infants point to the middle ear as a source of immature thresholds in quiet. The middle ear of an infant is less efficient than that of an adult in transmitting sound to the inner ear (Keefe, Bulen, Arehart, & Burns, 1993). The efficiency of high-frequency sound transmission through the middle ear improves considerably in the first year of life, with smaller progressive improvements across the frequency range of hearing continuing well into childhood (Okabe, Tanaka, Hamada, Miura, & Funai, 1988).

Interestingly, the inner ear seems to be mature in newborns. Nonetheless, electrophysiological measures show a broader neural response to high-frequency sounds, matching the results of behavioral studies of infants (e.g., Abdala & Folsom, 1995). Furthermore, transmission time of the neural response through the brainstem auditory pathway is correlated with young infants' ability to detect a high-frequency sound (Werner, Folsom, & Mancl, 1994).

Limitations in basic auditory abilities would be expected to limit the precision with which a young infant can represent a complex sound, such as speech. Researchers speculate that one reason adults speak slowly, more clearly, and at a higher intensity to infants is to compensate for infants' immature hearing.

Stage 2: Maturation of Selective Listening and Discovering New Details in Sound

By the time an infant is 6 months old, middle ear efficiency has improved and the transmission of information through the brainstem seems mature. However, behavioral tests of hearing still find higher response thresholds, in quiet and in noise, for infants at this age—and in fact, for children up to 4 years old (e.g., Schneider & Trehub, 1992). A small part of this immature sound detection can be due to simple inattentiveness, or infants' not being on task at all times during the test. However, most of the difference seems to result from the way infants listen to sound.

While an adult will focus on the frequencies in a sound that are expected to allow them to identify the sound, infants tend to listen in a broadband way. They listen to all frequencies rather than selecting the most informative. This difference is demonstrated in a simple task in which infants and adults learn to respond to a tone in noise (Bargones & Werner, 1994). On a large majority of the trials, the tone is presented at one "expected" frequency, but on some trials, a tone at a different, "unexpected" frequency is presented. Adults tend not to hear the unexpected frequencies, while infants detect the expected and unexpected frequencies equally well. The interpretation of this result is that infants listened for a broad range of frequencies, while adults listened only to the frequency at which they expected the signal to be presented.

Could it be that infants just don't form expectations about sound as adults do? Infants' performance in other tasks suggests that they not only form expectations but also direct their attention to increase their sensitivity to sound under some conditions. For example, if a short burst of noise is presented to cue the listener that the target sound is about to occur, both infants and adults could detect the target sound better when it occurred at the expected time, rather than at a slightly earlier- or later-than-expected time (Parrish & Werner, 2004). This finding suggests that the infants learned that the sound they were supposed to detect usually occurred at a specific time and that they listened for the sound at that time but not at other times. This conclusion means that infants have the capacity to listen selectively under certain conditions.

If infants can direct their attention to a particular time, why don't they direct their attention to a particular frequency? Researchers speculate that it is maladaptive for infants to listen selectively to a sound like speech, in which the important frequencies change depending on the speaker, the context, the language, and other factors. It may be more sensible for infants to continue to listen broadly to speech until considerable listening experience in many situations allows them to learn where the important speech cues occur. In fact, research suggests that adults learning a second language have difficulty in part because they listen to the aspects of speech they have learned to listen to in their native language, while ignoring cues in other frequency ranges that are important for the second language (e.g., Best, McRoberts, & Sithole, 1988).

One result of infants' broadband listening is that it makes it difficult for them to separate target sounds from competing sounds. Adults can have problems separating a target from competing sounds when the competing sounds change over time, and infants also have special difficulties when the competing sounds vary. For infants, though, just having a competing sound in the background seems to make it difficult for them to hear a target. For example, the presence of a competing sound, even one that is far from the target sound in frequency, increases infants' threshold for the target sound (L. J. Leibold & Werner, 2006). This susceptibility to interference from competing sounds appears to continue until children are 4 or 5 years old (L. Leibold & Neff, in press). This finding implies that learning about sound will be more difficult for infants and preschool children in noisy environments and those in which there are several competing sources of sound. Research underway in several laboratories is attempting to determine whether infants and children are able to use some of the strategies that adults use to separate target and competing sounds.

The development of selective listening involves not only picking out one sound among several, but also listening to the details in complex sounds such as speech. In a series of studies, Nittrouer (2006) has shown that young children tend to make decisions about the identity of a syllable or a word on the basis of global acoustic differences rather than on fine acoustic details. Nittrouer's findings are consistent with the idea that children do not focus in on specific frequencies. Apparently, it is only with years of exposure under a variety of conditions that children notice the details in speech.

Stage 3: Maturation of Perceptual Flexibility

By school age, children appear to have mastered selective listening: they are no longer as influenced by background sounds as younger children and they appear to focus on informative aspects of sound. School-aged children are still less consistent than adults in the way they categorize speech sounds, and researchers can still identify listening conditions that are more difficult for school-aged children than for adults.

Children are less consistent than adults in identifying speech sounds because once they have discovered the multiple redundant acoustic differences between sounds, they have trouble when all of those differences are not available to them. For example, Hazan and Barrett (2000) found that when they synthetically altered syllables so that they are distinguished by only one acoustic cue, 6-year-old children were much less consistent in identifying the syllables than when multiple acoustic cues were available. Older children and adults were as consistent at categorizing the syllables with one cue as with multiple cues. Similarly, in the presence of noise or reverberation, some speech cues may be difficult to hear because of masking or distortion, while others remain usable. Under such conditions, adults can switch to the more reliable cue, while children apparently cannot.

Finally, speech perception may be a relatively automatic process for young adults, based on years of practice. For school-aged children, however, perceiving speech in difficult listening situations may be less automatic, requiring greater attention and allocation of more processing resources. Any additional demands on attention may be impossible for children to manage. Wightman and Kistler (2005) showed recently that adults could separate two voices presented to one ear; their ability to do so was little affected by yet another voice presented to the opposite ear. Children ages 6-9, in contrast, could separate the two voices in one ear fairly well, but their performance deteriorated markedly when another voice was added to the opposite ear. One explanation of this result is that the adults could separate the original two voices because they had sufficient processing resources to block out the voice in the opposite ear, while the children required so much effort to separate the original two voices that they had no processing resources available to block out the third voice.

Implications of Auditory Development

Developmental studies of infants and young children are beginning to explain why difficult listening conditions are nearly always more challenging for children than for adults. Early in infancy, fundamental auditory processes limit infants' ability to represent the fine acoustic details in the sounds they hear. However, even after the auditory system is able to represent those details, infants and preschool children do not appear to use all the details available to them. It is as if the system remains unselective during this stage of development, so that children will learn to use the appropriate acoustic information even though the frequencies at which it will occur are uncertain. Finally, school-aged children seem to have the acoustic details available to them, and they are able to attend to those details. Auditory development in this final stage involves learning to use different details flexibly with changes in listening conditions and acquiring the practice needed to make speech perception an automatic process.

The results of these studies have implications in many realms. For the audiologist, they suggest that infants and children with hearing impairment need to hear the broadest possible range of frequencies to learn how to understand speech most effectively. For the speech-language pathologist, they suggest that children may not always hear all of the acoustic details in speech, even when those details are available to them. For those charged with designing the environments in which infants and children live and learn, they underscore the importance of reducing the levels of noise and reverberation to optimize auditory learning.

Interesting material.

A while back my kid accidentally crashed into my 805, the 805 and stand fell over. Luckily, the tv center stand caught the fall at 45 degrees. Fortunately, the 805 was bolted to the stand. If it wasn't, my 805 would have knocked down my tv, probably end up breaking the tv and my 805. It was a scary moment. ha ha

As much as they know not to ever go near the speakers (and they usually don't), accidents do happen. That's one of the reason why I'm in no rush to get 802's yet. Boys are bad. I don't trust the mischievous instincts of 2-3 year old boys. ha ha I'll wait until they both at least past 4 years old.

Good thing for you that it's not the diamond series. Expensive tweeters huh.