How to use sound-effects and music to give user feedback
You can only access your users’ sensory experience through three mediums: touch,sight, and sound.
It’s important to treat all three as integral to the app experience, and to consider where appealing to one sense is more helpful than appealing to another. It’s a mistake to assume that sound is not an important part of your app. Although you can get by with mute software, adding sound not only lends a finesse to your final
design, but lets you provide instantaneous feedback to users. Sound has become such an integral and exciting part of app design that there are now entire apps which use nothing but sound to orientate a user in their universe. Take a look at the app Papa Sangre for one beautiful example of this kind of work.
Sound is an obvious consideration for games or music apps, but is it necessary for a tax-return app, or a calendar?
The answer is, yes, it is still essential. Even if you ultimately choose to exclude sound, you are making the decision to deploy silence: which, as any musician knows, is specifically denoted on sheet music. Silence is also a meaningful “sound”, and needs to be incorporated wisely. Let’s take a look at a situation where sound
has been used horribly and for no purpose. You’ve probably worked in an office with someone who has a sound effect set up for every action their computer performs. When an email comes in, there’s a little ‘ping’ sound, and every time they delete a file, you hear a ‘woosh’ noise. After a short while, you want to peel your own face off, roll it into a trumpet and scream through it. system alerts are usually a terrible use of sound,
and one you should certainly avoid in your apps.
In our example office situation, the sound effects serve no purpose. The incoming email sound is so regular and intrusive that it soon becomes meaningless. In the same way, the file deleting sound serves little purpose:
It merely confirms an action that a user has already performed using their mouse. Giving audio feedback on top of this visual confirmation is pointless and therefore irritating.
Think carefully about sound, and the absence of sound. Are you giving your users essential audible cues to indicate non-visual events, or will you irritate them with the addition of mindless beeps and chirps?
Programmers will expect your sounds provided to them in a mainstream format: WAV, AIFF or MP3 or, in the case of Apple devices, AAC.
Keep an eye on file sizes; although there is really no limit to the size of a music file you include with your app, it may cause a small app to become ten times the size. Discuss sound requirements with your programmer and follow their advice.
Using sound to create an atmosphere in your app
Sound is a shortcut straight into your users’ emotions. You will probably have noticed how moving music in films and on television can add poignancy. Try watching an important scene in a film with the sound off: Do you feel the same emotional resonance now?
Similarly, the combination of sound with images can create emotionally evocative experiences - consider an app like Osmos HD, which is utterly mesmerising in its use of sound to enhance the visual experience.
In most apps sound could be used a little but, if you are creating a game or entertainment app, sound could not be more important. Smartphone gamers are often commuters, and will listen to their devices using headphones. Although you should provide the option, in code, for the user’s own audio library to override the in-game music, you should also assume the user may want to be listening to any music you provide.
Choosing appropriate sounds to enhance the atmosphere you create for your app could make the difference between a hit app and a desperate failure. On the next page you’ll find examples of apps that make amazing use of sound. Download some of these and use them as your yardstick.
There is one other kind of sound to consider, though it is more tactile than audible: It is the vibration feature on many smartphones. Sound is caused by vibrations and inside many modern smartphones is an device that can cause the entire unit to vibrate. Again, use this feature with caution, but be aware it is there. Often it can be used in games to indicate an impact, but you may find new and novel applications are possible.
Where to source free music
Here are some great places to find music for your app. Be sure to double check the licensing terms on every track you consider using:
• Soundcloud http://soundcloud.com/• ccMixter http://ccmixter.org/
• Magnatune http://magnatune.com/genres/
• Jamendo http://www.jamendo.com/en/?p=tags