We all know that the main ambition of slots developers, whether it is sound, game dynamics or overall graphic presentation, is to keep the player playing!

But how one goes about that is multifaceted and there are plenty of ways to skin a successful slot cat. What isn’t in doubt is the number of stellar software companies that now provide the energy and power behind UK online slots.

netenWe truly have an embarrassment of riches, with the likes of Yggdrasil, NetEnt and Iron Dog to name but a few.

When it comes to slot sound design the clear aim is to change a punter’s behaviour, not just prolong the session. If you can shape the decisions players make, all whilst leaving the player with the illusion that they are in control, then the battle is already half-won.

For many, the first memory of a slot was on a visit to the end-of-the-pier amusement arcade on a childhood summer holiday. The wall of sound that hit young ears as you stood in front of a row of slots, watching your father pour coins into in flashing box is something that never leaves you.

Technology may have improved in the interim years, but the goal is still the same; to keep your interest and keep you playing as long as possible.

Let us take a closer look at the psychology behind the audio soundscapes that enhance modern slot games at the popular online casinos in the United Kingdom.

The Psychology of Humans and Sound

As humans, we are programmed to be responsive to the slightest change in our aural environment; both for protection and for pleasure.

So carefully calibrated is our nervous system that scientists have proven that we have already interpreted a noise before we have even registered what it is. This primal trait leaves us alert and ready to respond and can even unleash a hormonal response.

The more all-consuming an audio environment is, the more distorted the perception of time becomes.

In the same way that people can meditate for hours listening to metronomic aural sound-baths or Gregorian Plain Chant, so can a well-rendered slot soundtrack reduce a player’s awareness of how long they have been playing for.

The usual connection with external cues becomes compromised and our attention is inevitably drawn to the dominant sound-provider.

A 2013 study showed that when a group of gamblers were analysed playing with the sound on and another group played the same slot but with the sound off, the “on” group demonstrated significantly increased arousal “both psychophysically and psychologically”.

Heart rates increased, perceptions of wins were exaggerated and a general positive spin was put on proceedings, well in excess of that experienced by the “silent” group.

Although punters tend to be overly optimistic when playing, regardless of other factors, the difference in outcome is still stark: the 15% overestimation of wins by the “silent” group became a 24% exaggeration for the group with the sound on.

Of course, this also means that an effective soundscape can lead to players underestimating losses as well.

Read the full study here.

Tricks They Use to Keep You Playing

Audio cues that are linked to rewards are a key component of the modern slot sound psychology.

Any win, however small, or any Bonus Feature, nudge or Free Spin, will be greeted by “winning” sounds, such as fanfares, chiming bells and the classic sound of cascading coins hitting the delivery tray.

Add to this list clapping, crowd noises (mimicking a goal being scored in a football match) and ever-more-extravagant cash register squeals and squawks and you have an entire aural arsenal.

Another old trick is the idea of “unresolved melodies”. This involves hooking you in to a familiar, if hard to pinpoint, melody and taking you on its musical journey…only to finish before the final beat.

This encourages the player to seek “closure” or “resolution” and to keep on spinning. Close, but no cigar is the ethos at play here.

The message the incomplete ditty is giving is “you are on the right path, one more push and it’s jackpot time!”.

As industry researcher Karen Collins explains succinctly; “we crave the final chord”.

This can also be seen in the “near-miss” sound-effect that slot players will be familiar with. The slow build in sound and then the disappointment when the ascending bonus ladder becomes a disappointing, descending snake.

Read more about sound impacts

But more doesn’t always mean more and one of the challenges facing sound designers is that of “sonic fatigue”, when a player’s aural senses are overwhelmed by the noise and they start to be driven away from the game they are playing.

In other words: don’t annoy the punter!

The array of noises and sounds must encourage, intrigue and excite a player without irritating, assaulting and alienating you.

Early fruit machines and slots tended to use tunes in the key of C-Major, as it has long been associated with happy and jolly thoughts and positive energy.

That principal is true to this day and while not all slots stick slavishly to this system, you might be interested to discover that your favourite slot’s genial and “peppy” soundscape is still based on C-major more times than you would think.

Tailoring Slot Sounds to Game Themes

This may seem obvious, but the eyes and ears need to be fed congruent things if slot soundscapes are to be truly effective.

For example, if you are playing a fishing game, much of which may take place under water (see Big Bass Bonanza or Lucky Larry’s Lobstermania), it is no use having desert-themed sounds dominating, like tumbleweeds and rattlesnakes!

Likewise, if you are in deep space enjoying a sci-fi slot (see Starburst and Reactoonz), farmyard sounds, however fantastically rendered, will do little to keep the player’s attention on the game.

Until space cows become a thing, the discord and weird juxtaposition between two competing themes will only serve to take the slot player away from the action and not immerse them in it.

We can also think of slot sounds being delivered on several levels, or layers.

We have the nudge and win sounds that respond and react to each spin and to what is happening specifically in the game, but there are also background themes that remain constant during play.

For example, a beach-themed slot, like Tropicool 2 and Jumbo Juicy, will benefit from steel drums and Hawaii-esque sounds, matching the action on screen.

This “ambient audio” works across all genres, including Egyptian slots and Haunted House thrillers.

The Illusion of Control

Giving punters the illusion of control is another key aim and, arguably, the most important one of all.

No one likes to be taken for a mug or feel they are being unduly manipulated and a clever sound engineer will do their best to reduce that feeling, or take it away entirely.

By linking each button press or in-game choice to a specific sound, the hope is that the player will quickly come to associate each action with free-will and individual autonomy.

This will then extend his or her playing time and give the impression of “being the boss”.

Of course, players can always choose to turn the volume down or even off; the ultimate act of aural autonomy!

The British Gambler’s Thoughts

At some level, in this world of hyper-modernity, we all know we are being manipulated to some degree. Punters are no different.

Whether we are sitting playing our favourite slot on the number 19 bus with our ear buds in or plugged into the desktop surround-sound at home, the audio input is a major factor in our play.

Slots need impressive and immersive soundscapes, both to steer the play and to enhance the themes and graphics.

Thanks to a deeper understanding of science and the psychology behind aural manipulation, slots today have an ultra-sophisticated ability to mould, shape and direct our play.

As long as we are aware of this, we can all continue to enjoy our favourite slots. Of course, we could just turn the sound off, but why miss out on all the fun?!