Playing upbeat pop music to wake you up is the key to having a successful day at work or school, according to new research.
Sounds such as the Beach Boys' 'Good Vibrations' or The Cure's 'Close To Me' work better than an alarm clock.
The finding could lead to personalised apps that 'Wake Me Up Before You Go Go', say scientists.
Catchy tunes help people rise and shine with a spring in their step instead of 'singing the blues' on their way to their office, factory or college.
Lead author Stuart McFarlane, a doctoral researcher, said: "You would assume a startling 'beep beep beep' alarm would improve alertness.
"But our data revealed that melodic alarms may be the key element. This was unexpected."
His team at RMIT University, Melbourne, analysed the impact of the waking habits of 50 people.
Those who used the 'Sound of Music' to open their eyes were mentally sharper for the next few hours. Harsh alarm tones were linked to daytime drowsiness.
Co author Professor Adrian Dyer said: "We think a harsh 'beep beep beep' might work to disrupt or confuse our brain activity when waking.
"A more melodic sound like the Beach Boys 'Good Vibrations' or The Cure's 'Close to Me' may help us transition to a waking state in a more effective way."
A specially designed online survey enabled the volunteers to remotely take part in the study from the comfort of their own home.
Each individual logged what type of sound stirred them out of bed. They then rated levels of grogginess and alertness against standardised sleep inertia criteria.
Prof Dyer said: "If we can continue to improve our understanding of the connection between sounds and waking state, there could be potential for applications in many fields, particularly with recent advancements in sleep technology and artificial intelligence."
The surprising discovery reported in PLoS One may have important implications for those who need to quickly be at their best, such as shift workers or emergency first responders.
Being confused, clumsy or sluggish increases the risk of car crashes in motorists as their reaction times are slower.
Plane crashes have also been known to happen when pilots have taken the controls just after a nap.
Morning grogginess - or sleep inertia - is a serious problem in our 24-hour world, warned the researchers.
Mr McFarlane said: "If you don't wake properly, your work performance can be degraded for periods up to four hours, and that has been linked to major accidents.
"You would assume a startling 'beep beep beep' alarm would improve alertness, but our data revealed that melodic alarms may be the key element. This was unexpected.
"Although more research is needed to better understand the precise combination of melody and rhythm that might work best, considering most people use alarms to wake up, the sound you choose may have important ramifications.
"This is particularly important for people who might work in dangerous situations shortly after waking, like firefighters or pilots, but also for anyone who has to be rapidly alert, such as someone driving to hospital in an emergency."
The research could help contribute to the design of more efficient interventions for people to use on their own devices to wake up properly.
Prof Dyer said: "This study is important, as even NASA astronauts report sleep inertia affects their performance on the International Space Station."
The researchers described the phenomenon as "a potentially dangerous reduction in human alertness." It occurs up to four hours after waking.
The type of sound people set as their alarm for waking has been shown to reduce the effects. But the part music can play has remained unclear.
Added Mr McFarlane: "The analysis did reveal a sound which is ranked as melodic by participants shows a significant relationship to reports of reductions in perceived sleep inertia.
"In contrast, sound rated as neutral - neither unmelodic nor melodic - returns a significant relationship to the reports of increases in perceived sleep inertia.
"Considering that the implementation of auditory assisted awakening is a common occurrence, the musical elements of a chosen waking sound may be an area to further interrogate with respect to counteracting sleep inertia."