Shockwave-Sound Blog and Articles

Free sound effects pages back by popular demand

Back in the good old days, when our site had the “old style” look and feel, and about half as much content as we have on the site now, we used to have a selection of “Free sound effects” pages. It wasn’t really anything very fancy, just a bunch of pages from which users could download sound effect files completely free of charge.

We re-designed and did a complete overhaul of the website in October 2015 and the new-look site had a more focused approach, with less clutter and more straight to the point, with high-quality sound effects and royalty-free music that we wished to focus on.

Turns out that people are missing those old free sound effects pages. Having received numerous calls for their return, we’ve listened and finally got them back. Here they are.

Just a reminder – the sounds available on these free sound effects pages are of varying quality levels, some good, some pretty bad. We didn’t make the sounds. We just gathered them and described them for you. We also cannot grant any license for them, other than strictly personal / home use. If you want sound effects of consistently high quality and with a real license to use them in your own productions, then be sure to buy the professional level sound effects which you can find by searching or browsing from our main home page.

We currently have the following pages of completely free sound effects:

We hope you’ll find some use, or just some pleasure or amusement out of these sounds. Remember — home use only. No license granted for these.


Harnessing the Power of Sound: Behavior and Invention

Harnessing the Power of Sound: Behavior and Invention

Sound is a force of nature that has its own special and unique properties. It can used artistically to create music and soundscapes and is a vital part of human and animal communication, allowing us to develop language and literature, avoid danger, and express emotions.  In addition, understanding and harnessing the unique properties of sound has resulted in some surprising and fascinating inventions and technologies. Below are some interesting notes on the behavior of sound and some novel technological uses, both as a weapon and in contrast in medicine and health care.


The Speed of Sound
Sound exists when its waves reverberate through objects by pushing on molecules that then push neighboring molecules and soon. The speed at which sound travels is interesting as it behaves in the opposite manner of liquid. While the movement of liquid slows down depending on the density of the material it is trying to pass through, for example cotton as opposed to wood, sound actually speeds up when faced with denser material. For example,sound travels in Air (21% Oxygen, 78% Nitrogen) at 331 m/s, 1493, m/s through water, and a whopping 12,000 m/s through Diamond. 
This sound behavior is also evident in how quickly it can pass through the human body, which is generally around 1550 m/s, but passes much more quickly through skull bone at 4080 m/s which is much denser then soft tissue. Interestingly, the average speed through the human body is very similar to that of water, which makes sense because human beings are 90% made up of water.

Sound in a Vacuum


Not only does the density of objects increase the speed ofsound, sound needs material to be present in order to “make sound” inthe first place. Because, it exists when sound waves reverberate through objects. Without objects present, sound does not exist, such as is a vacuum. his makes as a vacuum is an area of space that is completely avoid of matter and therefore has no molecules. This video demonstrates the effect of a vacuum on sound. As the air is sucked out of the bell jar, the bell can no longer be heard.
Sound is in the Ear of the Earholder


For humans and animals, the perception of sound waves passing through their ears, depends on the shape of the ear, which influences that vibrations. The shape of an animal’s outer ears determine the range of frequencies that they can hear. Elephants have flat and broad ears, which allowthem to hear very low frequencies, which they use to communicate. Lower frequencies are associated with large surface areas, such as bass drums, so this makes sense. Mice have ears that are round, which allow them sensitivity to sounds that come from above. Again, this makes sense as they are tiny and close to ground and all threats would be coming from above: hawks wanting to
eat, cats hunting, humans screaming and jumping on chairs, etc. The tall ears of rabbits make them sensitive to sounds flying around horizontally, obviously so they know when to jump. Owls work their famous head pivot to create a precise sound listening experience while checking for prey and threats. Deer work to avoid predators with muscles in their ears that allow them to point in different directions.
Sound as a Weapon
 The Long Range Acoustical Device (LRAD) is a machine used to send messages and warnings over very long distances at extremely high volumes by law enforcement, government agencies, and security companies. They are used to keep wildlife from airport runways and nuclear power facilities. The LRAD is also used for non-lethal crowd control. It is effective in crowd control because of its very high decibel range which can reach 162. This exceeds the level of 130 decibels, which is the threshold for pain in humans. It is very precise and can send a “sound beam” between 30 and 60 degrees at 2.5kHZ and will scatter crowds that are caught within the beam. Those standing next to it or behind it might not hear it at all. But those who do report feeling dizzy with symptoms of migraine headaches.  This is called acoustic trauma and depending on the length of the exposure and it’s intensity, damage to the eardrum may result in hearing loss. Since 2000, the LRAD has been used in many instances of crowd control throughout countries in the world, and even on pirates attempting to attack cruise ships.
Almost humorously, high pitched alarms can also be used to deter teenagers from loitering around shops or engaging in vandalism and drug activity. The “teenage repellant” has been used throughout Europe and the US. Since teenagers have a higher frequency range of hearing than adults, it targets them specifically, while adults are spared the annoyance of the 17.4KHz emission. There are critics that state these devices unfairly target specific groups (youth) and are therefore discriminatory.
Sound Levitation
Sound levitation, or acoustic levitation, uses sound properties to allow solids, liquids and gases to actually float. It uses sound wave vibrations that travel through gas to balance out the force of gravity and creating a situation in which objects can be made to float. Dating back to the 1940s, the process uses ultrasonic speakers to manipulate air pressure and points in the sound wave that counteracts the force of gravity. A “standing wave” is created between a “transducer,” such as a speaker and a reflector. The balancing act occurs when the upward pressure of the sound wave exactly equals the force of gravity. Apparently the shape of liquid such as water can be changed by altering the harmonics of the frequencies that result in star shaped droplets.
In terms of practical uses of sound levitation, they do improve the development of pharmaceuticals. When manufacturers create medicines they fall into two categories called amorphous and crystalline. The amorphous drugs are absorbed into the body more efficiently than crystalline drugs. Therefore, amorphous are ideal because a lower does can be used so they are cheaper to create. So, during evaporation of a solution during manufacturing, acoustic levitation is because it helps prevent the formation of crystals because the substance does not touch any physical surfaces. Acoustic levitation, in others words stops substances from crystallizing, thus creating a much more efficient method of drug creation. In addition, sound levitation creates essentially a zero-gravity environment and is therefore an excellent environment for cell growth. Levitating cells makes sure that a flat shape is maintained which is the best for the growing cell to absorb nutrition. It could also be used to create cells of the perfect size and shape for individuals.Sound behaves in its own fashion and is a phenomenon that can be used in force and in healing. It taps into the physics of the natural world and through its interaction allows for all sorts of human invention. Surely, sound will continue to be researched and pursued as a powerful natural element to be used in a myriad of new ways.


Google Close Captions Sound Effects

Google Close Captions Sound Effects

Google, ever the inventors of new technology and the owners of, have broadened their work into the area of sound effects, specifically through the audio captioning on their YouTube network. Traditionally “closed captions,” which provide text on the screen for those with hearing challenges, provided dialog and narration text from audio. Now, however, Google has rolled out technology that can recognized the .wav forms of different types of sounds to include on their videos, dubbed “Sound Effects Captioning.” They do this to convey as much of the sound impact as possible from their videos, which is often contained with the ambient sound, above and beyond the voice.

In “Adding Sound Effect Information to YouTube Captions” by Scorish Chaudhuri, Google’s own research information blog, three different Google teams, Accessibility, Sound Understanding, and YouTube utilized machine learning (ML) to develop a completely new technology, a sound captioning system for video. In order to do this, they used a Deep Neural Network (DNN) model for ML and three specific steps were required for success: to accurately be able to detect various ambient sounds, to “localize” the sound within that segment, and place it in the correct spot in the caption sequence. They had to train their DNN using sound information in a huge labeled data set. For example, they acquired or generated many sounds of a specific type, say “applause,” to be used to teach their machine.

Interestingly, and smartly, the three Google teams decided to begin with 3 basic sounds that are listed as among the most common in human created caption tracks, which are music, applause, and laughter: [[MUSIC], [APPLAUSE], and [LAUGHTER]. They report that they made sure to build an infrastructure that can accommodate new sounds in the future that are more specific, such as types of music and types of laughter.  They explain a complex system of created classifications of sounds that the DNN can recognize even multiple sounds are playing, meaning the ability to “localize” a sound in a wider variety of simultaneous audio. Which, apparently they were successful in achieving.

After being able to recognize a specific sound such as laughter, the next task for the teams was to figure out how to convey this information in a usable way to the viewer. While they do not specify which means they use to present the captioning, the different choices seem to be: have one part of the screen for voice captioning and one for sound captioning, interleave the two, or only have the sfx captions at the end of sentences. They were also interested in how users felt about the captions with the sound off and interestingly, discovered that viewers were not displeased with error, as long as the majority of time the sound captions communicated the basic information.  In addition, listeners who could hear the audio did not have difficulty ignoring any inaccuracies.

Overall this new system of automatically capturing sounds to display as closed captioning via a computer system as opposed to a human by hand looks very promising. And, as Google has shown time and time again, they don’t seem to have a problem with the constant evolution of products that succeed and that users value. They stress that this auto capturing of sound increases specifically the “richness” of their user generated videos.  They believe the current iteration is a basic framework for future improvement in sound captioning, improvements that may be brought on by user input themselves. raising the bar for audiophile media producers raising the bar for audiophile media producers

As of January 2010, we at are pleased to announce that we are introducing a new level of audio quality for royalty free music users. We’re releasing all our new music — and some of our back catalogue — as High Definition, 24-bit WAV audio files.


It has been almost 10 years since our launch in March 2000, and in that time there has been a general move towards bigger, better media. Video has moved from standard resolution to high definition. File sizes have grown tenfold, and both professional and consumer oriented media production programs have become better and better equipped to deal with images, video and audio of higher and higher resolutions.

As I’m writing this, there are no other royalty-free music shops or sites that offer high definition 24-bit stock music, that I’m aware of. Doubtlessly, others will follow. Pretty much the same thing happened about 5-6 years ago when we were the first to start selling uncompressed WAV files in full CD-quality while the norm was that royalty-free music generally came as MP3 or, on Audio-CDs that you had to wait for and receive them physically by post.

What is High Definition Audio?

I’m not going to turn this into a very complex discussion on ‘audiophile’ issues but I would like to take one minute to talk about what the difference between a “regular” 16-bit WAV file and a “high definition” 24-bit WAV file means.

As we know, audio exists as fluctuations in pressure, or “sound waves”. These waves are really completely analogue, meaning that they are “natural” and soft sound waves that moves through the air.

The concept of “sampling” audio means that we capture a series of “moments” in the sound wave, and each time we capture that moment, we store that moment as a number in RAM (or on hard disk). When we talk about 44100 Hz (or 44.1 khz) sampling rate, we mean that we “capture the moment” in the sound wave 44100 times per second.

We can then re-create the audio by playing back all these “captured moments” in the same order they were captured. This is how we “sample” a sound and play back the sample.

Take a look at this illustraton:

The number of times per second that we capture the sound is known as the sample rate. The more often we capture the sound, the higher the sample rate, and the more “naturally” we’ll be able to capture the true sound wave. This is illustrated along the horizontal line above

Now, the other value that’s worth noticing here is the vertical scale. The finer the resolution of this scale, the more accurately we are able to capture each moment of sound. This value is known as the bit depth and like the sample rate, it determines how close to the original, true sound wave we are able to recreate the sampled sound.

Here comes the science part…

Why is the bit depth so important? Because the higher the bit depth, the more precise each sample can be measured. It’s no good sampling the sound 100,000 times second if, every time the sound value is stored, it cannot be stored using a precise value.
With a bit depth of 16, each sample can be stored by using a number from -32,768 to +32,768. That’s 65,536 possible different values that each sample can have.

And with a bit depth of 24, each sample can be stored using any value from -8,388,608 to +8,388,608. That’s a total of 16,777,216 different values that each sample can be stored at.

The aging CD (Compact Disc) standard

The good old Compact Disc, launched in the 1980’s, set a very strong standard when it came on the market. The Compact Disc (CD) operated with a sample rate of 44100 Hz (44.1 Khz) and a bit depth of 16. This is why, to this date, we always refer to “CD quality sound”, when we mean that the sound has been captured 44100 times per second, with 16-bit depth (i.e. values between -32,768 and +32,768 each sample). Audio folks also refer to this as (16-bit 44khz), or simply 16/44.

Since then, new technologies have implemented higher sample-rates, such as 48 Khz (48000 samples per second), 96 Khz, or even 192 Khz in some extreme cases. And these days, even cheap video and audio processing software can easily handle 24-bit audio. However, the “CD quality” audio at 16-bit, 44.1-khz is stubborn! It has dug its way into our psyche as “full CD quality”, as if in some way, that’s the best we’ll ever get.

Today, though, more and more people work at 24-bit. Most of our contributing music composers/producers have already produced their music at 24-bit for a couple of years. It’s just that we, like others, have actually downgraded the audio to 16/44 before putting it up for sale.

Why? Well, file sizes for one. A file at 24-bit is 50% larger than a file at 16-bit. So whereas stereo audio data 16/44 uses approximately 10 MB per minute of audio, 24-bit is up to about 15 MB per minute. And if you also increase the sample rate from 44.1 khz to 48 khz, then you’re increasing the file size by another 10% or so on top of that, so then you’re up to approx. 17 MB per minute of audio.

But that’s not all. Because we also have to cater for those who cannot use the 24-bit file, we have to include the 16-bit file too. So that’s another 10 MB per minute of audio, and now we’re up to about 27 MB for each minute of audio.

For a 5-minute music track, delivered in 24/48 and in 16/44 you’re looking at around 135 MB file size.

The Terrabytes are flying…

That’s not peanuts, when you consider that a music library such as ours have thousands of music tracks, often times also available in several different versions, mixes, cuts and edits. If this 5-minute audio track is also available in three different mixes (say, a version without vocal and a version without drums?), then you’d be up to an incredible 405 MB of files, just for this 5 minute track. And we still haven’t counted the loops!

It goes without saying, the demand for web server space is enormous (Terrabytes are flying!) and the same goes for the traffic volumes (i.e. the amount of data that has to travel from our server to all the thousands of people who use the website and download audio).

Nevertheless, we are now moving to 24-bit, and you’ll see all our new music coming up on the site in 24-bit. We’ll also try to work our way through some of the back catalogue and, where possible, add 24-bit files to the webserver. This will take time, though, as we’re pretty much already working flat-out here and, we ask for your understanding that not all the older music on our site was actually ever produced in 24-bit. Some of it was recorded, mixed and mastered in 16-bit from the beginning, and in those cases, it would be pointless to add 24-bit files. We won’t convert a 16-bit sound file up to 24-bit. We’ll only offer 24-bit files where the music has actually been produced in 24-bit from the beginning.

In some cases, you’ll see that some versions of the track (for example, “full length version”) is available in 24-bit, but the other versions (such as “set of music loops”) is only available in 16-bit. This probably means that the composer/producer sent us his track in 16-bit. We then used that 16-bit file to create the loops. Now, when we later asked the composer/producer to send us the 24-bit file, he sent only the regular, full-length version. And it would be a pretty hopeless task for us to edit the same versions/cuts/loops again. So – in this case we’ll simply add the 24-bit file of the normal full-length version, whereas the other “edited versions” (60-secs, 30-secs, loops) remain only in 16-bit.

16-bit files also still included

Not all software can handle 24-bit audio files. I believe, for example, Windows Media Player cannot play a 24-bit sound file. Because of this, we will always include the 16-bit file as well.

That’s why, when you see a version described on our site as (wav+wav24) it means that the download is actually a .zip file which, when opened, you’ll find two WAV files inside. One WAV file is at 16-bit, 44.1 khz (good old trusty “CD-quality”) and another WAV file is at 24-bit, and either 44.1 khz or 48-khz.

We hope, and think, that this can help your project sound better! Thanks for reading.