I had a baby, therefore I am sleepy.When my wife gave birth to our first child in May, it was the best thing to ever happen to me. The baby has been a joy and her smile is the highlight of each day.But inevitably those smiles turn into crinkled noses and then, seemingly out of nowhere, wails.My daughter sleeps through the night but actually getting her to sleep is the most challenging part of parenting. She takes good daytime naps, but at night she remains wide awake and she gets fussy if we put her in the crib. She's too young to let her cry it out. Right?We've scoured books and the Internet but have found no definitive answer. So I asked the experts:"What music, if any, soothes a baby so deeply that he or she will go to sleep?"Lisa Huisman Koops, an associate professor of music education at Cleveland's Case Western Reserve University, said in an email that the key for parents is to model enjoyment in listening. "When children grow up in a home in which parents enjoy listening to various types of music at different points in the day â getting ready for the day, during meals, in the car, when relaxing, during family dance parties in the living room â the children learn that music adds to the richness of daily life."Koops said researchers have found that young infants recognize voices and music they heard while in utero. She's seen it in her own children. "My 1-month-old loves to hear his 7-year-old sister practice the violin, a sound he heard often before birth," Koop said. "The lullaby we sing every night to his 2-year-old sister is also calming for him."As for putting an infant to sleep, "various children react differently to music as part of the bedtime routine," she said. "It may become a 'sleep crutch' for some and disruptive when it turns off."Carol Weingarten, an associate professor at Villanova's College of Nursing in Pennsylvania, instructs her students to use music to soothe babies, but with the right sounds. "Babies, like older children and adults, do respond to music, and music seems to foster development and stress management," she said. "As for anyone, volume does have an impact, so extremely loud music and noises and harsh sound vibration can be unsettling."She said throughout history, babies have snuggled and slept to the sound of parents' singing whatever is considered a lullaby in their culture. "In clinical, I've seen babies calm to the sound of a nurse's soft singing, [so I] educate my students about the importance of verbal interaction with the newborns they care for, and that includes singing."Through the years, Weingarten students, especially those caring for newborns, have put her singing lessons to the test and they "are surprised by the way the babies will gaze at them intently, then calm and sleep," she said. "I am not an expert on what type of music is thought 'best' these days or scientific specifics of why music is great. I also don't think any particular type of music was ever proven to be 'best' for all babies," she said. However, "Thinking of Salt Lake City some of the recordings of the world-famous Mormon Tabernacle Choir are awesome at any age. Music can be viewed as a supportive (and some would say essential) part of parenting and infant care and can foster feelings of peace, stress relief and comfort for living beings of all ages."Lisa Roth is creative director and executive director of CMH Label Group's popular line of "Rockabye Baby!" albums. Since 2006, that included instrumental lullabies from rock artists ranging from KISS to the White Stripes. More than 50 albums have been released using xylophones, bells and marimbas to create a mood. In a phone interview, Roth said she and a co-worker came up with the idea while shopping for a baby shower gift. "I was dismayed to see a lack of parent-friendly music," she said. "From the artwork to the music, [the albums for sale] were all unoriginal and bland." With the help of producers and musicians not to mention good taste in music her label rolled out the line in 2006 with three albums that contained lullaby renditions of Metallica, Coldplay and Radiohead songs. Roth describes the music as "produced by elves and sprinkled with fairy tale dust."The goal is to create lullabies that are "soothing for the baby, but still recognizable for the parents," she said, noting that "Parents shouldn't put their pre-baby music on the back burner." While Roth said she doesn't place too much importance on studies that test the albums' effectiveness, the exploding popularity of the series shows that word-of-mouth is spreading.Josh Rutt is a New York-based music teacher, composer and performer who also is founder and CEO of Baby Blanket Music, a competitor of "Rockabye Baby!" Rutt created Baby Blanket Music nearly five years ago because he found the quality of baby music lacking.He, too, produces albums containing lullabies from famous musicians. The artists are generally more pop-oriented and include Justin Bieber, Lady Gaga and Garth Brooks."A lot of [my competitors' music] was overly simplified, and, to my ears, not particularly appealing," he said. "I'd like to make the music enriching and enjoyable for the child, and more enjoyable for the parents." He recommends that his albums also be used in the car, so that the child has the tripled sensation of motion, vibration and sound that many children seem to enjoy. Alex Doman is the Utah-based founder and chief scientist for Sleep Genius LLC, which sells two downloadable apps: Sleep Genius for adults and Sleep Baby Genius for babies and children for $4.99 each. The baby app has two settings: one for bedtime and another for naps. It features traditional lullabies with the sound of harps, violins and flutes, and a rhythm of 30 to 60 beats a minute.In a telephone interview, Doman said his apps include smart-sounding principles, including "neurosensory algorithms," which trigger a motion-induced sensation in brains, similar to a baby being rocked to sleep; "pink noise" that blocks out distracting noises while slowing down the breath and heart rate; and, most important, "psychoacoustic music," which helps people fall asleep faster with the use of low-frequency, low-tone density and low-tempo music. Doman said he required all of the musicians who performed the music to be parents. His intent was to create music with an undefinable sense of love and support. In addition, "consistency is important in all sleep routines," he said, and the regular use of certain sounds can help the baby gradually realize when it is time to sleep.Harvey Karp, an assistant professor of pediatrics at the University of Southern California School of Medicine, is the best-selling author of "The Happiest Baby on the Block," "The Happiest Toddler on the Block" and, most recently, "The Happiest Baby Guide to Great Sleep." His books have become a bible for parents. The techniques re-create a womb experience for babies, said Karp, who believes babies experience a "fourth trimester" during the first three months of life. Karp is a proponent of what he calls the "calming reflex," which causes babies to relax when they are given clues that they are safe inside the womb. There are five parts called the "Five S's": swaddling, side/stomach position (but never during sleep), shushing, swinging (gentle jiggling, especially of the head) and, finally, sucking (pacifiers or fingers). In a telephone interview, Karp said he is a big believer in white noise, which constitutes part of the "shushing," because the sounds can be similar to the loud noise fetuses hear in the womb. While a high-pitched sound can calm babies, to get baby to rest, parents should use lower-pitched rumbling noises, similar to the sounds of a hair dryer, vacuum cleaner or the sounds associated with being on trains, planes and automobiles."White noise is a teddy bear," said Karp, who markets a CD that includes three tracks of calming music, in addition to sleeping music. He recommends finding a noise that parents and baby like, and then using the "repeat" feature on the CD player all night. After the fourth trimester, Karp said music becomes another sleep cue and lullabies can be part of the bedtime ritual. Babies can learn the rhythmic pattern of the music, and it helps them create order out of chaos.I will try all techniques in hopes of reacquainting myself with an old friend, sleep. Next question: How do you persuade a baby to take a pacifier and not spit it out every time it reaches her lips?