Understanding Sound Signatures

When it comes to choosing audio equipment such as headphones or speakers, sound quality is a top priority. But what exactly is “sound signature,” and how does it affect the audio experience? In audio terms, sound signature refers to the unique characteristics of the sound produced by a particular device or system. These characteristics can include factors such as frequency response, dynamic range, and tonal balance, and they play a critical role in determining the overall sound quality and “feel” of the audio. In this article, we’ll explore the concept of sound signatures in more detail, discussing the different types of sound signatures and how they affect our perception of audio quality.

When you are able to comprehend how sound signatures function, you will be better able to understand product reviews that cover the more technical aspects of the speaker. It will enable you to choose a product that most closely matches your search criteria.

Understanding how we perceive sound, or transduction as it is known in science, is the first and most crucial concept. Simply put, when a sound is produced, air pressure fluctuations take place, which are then translated into vibrations by a number of parts in our ear and transformed into electrical signals that our brain can recognize as sound.

We can hear frequencies between 20Hz and 20kHz, which are identified as variations in air pressure. The frequency response is crucial when evaluating an audio device’s performance based on its technical specifications because it gives us a general idea of what frequency bands may or may not be emphasized or lacking.

For instance, one speaker might place more emphasis on the bass response while having poor high-end definition, whereas another might have strong bass but poor high-end definition. These are known as sound signatures, and the majority of consumer-grade audio equipment uses one of the following widely accepted signatures.

Types of Sound Signatures

Flat Sound Signature

Examples	Studio reference monitors, open-back headphones, professional in-ear monitors
Best for	Critical listening, recording, mixing & mastering
Works Well With	Any musical genre can be appreciated on a flat response system, but listeners who prefer bass-driven music might find a flat signature uninteresting.

Flat frequency responses are preferred by sound engineers and audiophiles because they give the listener the most accurate representation of the musical content as it was when it left the recording studio.

Flat sound signatures might be boring to casual listeners because most consumer-grade electronics are made to emphasize specific frequency bands. It is important to remember that no device is completely flat, and our ears do not perceive frequencies in a linear way either. Given that they are used for more formal applications, flat response devices are frequently more expensive.

Balanced Sound Signature

Examples	Studio monitors, audiophile headphones or speakers, PA systems
Best for	Critical listening, audio engineering, radio, gaming, TV
Works Well With	All music genres, spoken word

A slightly enhanced flat response can be used to describe balanced sound signatures. Balanced devices deliver a satisfying listening experience that can be regarded as reasonably accurate to the original source by incorporating slight enhancements and cuts in particular frequency bands as opposed to having an entirely flat signature.

U-Curve Sound Signature

Examples	Hi-Fi or home stereo systems, most earphones, and headphones
Best for	Casual listening, radio, gaming
Works Well With	All music styles, spoken word

One of the most well-known sound signatures is the U-Curve, which emphasizes the low-end and high-end while having a slightly scooped midrange. By increasing low-frequency content, adding warmth and additional “pump” to a track, and enhancing the treble region, which enhances vocal clarity and creates a warmer tonal signature overall, this sound signature improves the “exciting” content in music.

V-Curve Sound Signature

Examples	Car audio, Bluetooth speakers, many earphones/headphones
Best for	Casual listening, radio, gaming
Works Well With	Electronic music, pop, hip-hop, metal

Along with the U-Curve, the V-Curve is arguably the sound signature that is used the most. The U-Curve sound signature can be thought of as an enhanced version of the V-Curve. Although the sound you’re hearing differs greatly from the original source signal, for some people it greatly improves the overall listening experience.

Bass Boost

Examples	Dance-music specialty speakers & headphones, car audio, Bluetooth speakers
Best for	Casual listening
Works Well With	Electronic music, hip-hop

Another of the more popular sound signatures is boosted bass, which is frequently offered as an extra feature on many Bluetooth speakers and can be enabled or disabled at your discretion. Although a bass boost signature brings the low end to life and undoubtedly gets the dance floor going, this frequently leads to a serious decline in the upper midrange and treble clarity.

Treble Boost

Examples	Specialty speakers and earphones, smaller Bluetooth speakers, or cheaper devices
Best for	Casual listening or hard-of-hearing listening
Works Well With	Orchestral, spoken word

Whatever source signal is being fed through the device has its overall sonic qualities brightened by a treble boost sound signature. Although it’s not a typical signature, portable playback systems occasionally have it as an extra feature.

As our perception of the higher frequencies is frequently the first part of our hearing range to suffer through aging or exposure-related accidents, a treble boost signature can be helpful for those with hearing loss.

Cheaper audio equipment can occasionally give the impression of having a treble boost signature when in reality the speaker simply lacks the power to accurately represent the low end. The same is true for small speakers that have trouble with bass response.

The Harman Curve

In 2010, the parent company of numerous well-known brands, including JBL, Lexicon, DBX, and Crown, Harman International, created their own sound signature, dubbed the Harman Curve.

The ultimate goal of the Harman Curve signature is to bring the best elements of everyone’s favorite sound signatures together to produce a signature that as closely resembles a room full of speakers as possible. It is obvious from the perspective of an audio engineer that it is based on a U-Curve with some additional frequency spectrum adjustments, almost a well-balanced middle ground between a Balanced and U-curve signature.

Many of their audio products, including the well-known JBL brand, use the Harman Curve. This is what creates the distinctively strong tonal structure of JBL speakers.

How to Develop Your Own Sound Signature

You can alter the sound signature of many Hi-Fi/Stereo systems, car heads, and Bluetooth speakers using either a variety of EQ presets or a fully-customizable EQ to create your own sound to best suit your listening preferences.

EQ’s ability to change your sound signature will vary depending on the product. Some products only permit alterations to relatively broad bands of frequency, whereas others provide a more precise adjustment that allows you to change each 100Hz or more.

When using Bluetooth speakers, your EQ control is typically quite constrained. However, if you’re using a computer, you can easily download impressive EQ software that will enable you to fine-tune the sound signatures of your headphones or speakers to an impressive degree.

Just be aware that if a speaker is unable to handle the frequency content, extreme boosting of certain frequency regions may cause it to distort or even blow. Here are some easy rules to follow if you want to make your own EQ patch.

• To add sub-bass fatness: between 16Hz and 60Hz, give it a slight boost. Depending on the device, you might not have access to this area and, no matter how much you boost, you might not even be able to hear the difference. This frequency range is one that is frequently ‘felt’ rather than heard, and some speakers may not always be able to reproduce it.
• For a general bass boost: Depending on the instrumentation providing the low end, the majority of a track’s bass will fall between 60Hz and 250Hz. Playing around in this frequency range will give your system’s tonal qualities a little more depth, but be careful because a speaker not made to reproduce these frequencies at a high output level will easily burst or distort.
• For warmth: Take a look at the 250Hz to 2000Hz frequency range. There is a lot of character in this part of the frequency spectrum, but adjustments should be made carefully.
• For vocal intelligibility: This area contains a lot of the vocal character of a performance, but it should also be used with caution because too much boosting here can produce odd artifacts in the voice and, depending on the instrumentation of the song, could result in distortions or speaker failure.
• For improved brightness: Examine the 4 to 6 kHz frequency range. A slight improvement here could even bring unnoticed instruments to life because this is where many of the finer details are found. Use this frequency band carefully as it can also influence how “punchy” a track is perceived.
• For finer details and air: Between 6 and 16 kHz, give some small boosts. While enhancing this area can really make a song come to life, doing so excessively can make the music sound harsh and wear out the listener’s ears.

Additional Factors

In addition to an audio system’s sound signature, the following factors must also be taken into consideration when evaluating an audio device’s sonic performance:

Price

We can often learn how an audio device might sound by looking at the price of the device. Cheaper units are made of lower-quality parts, including speaker enclosure construction, Bluetooth codec, connectors, and driver materials.

Cheaper systems typically have trouble with the low end and frequently have poor overall sound quality.

Brand

How satisfied you are with your new audio device will undoubtedly depend on the brand or intended use of the device.

In the same way that a jazz listener might not like a heavily bass-boosted speaker system, a bass head who only listens to electronic music styles that demand emphasized low-end won’t be particularly excited by a flat response system. Pro audio brands are a better choice than top-tier consumer brands if you’re looking to purchase a device for critical listening.

Speaker Placement

Speaker placement is yet another crucial factor to take into account. If you want to get the most out of your new sound system, it’s worth looking at an installation guide to determine speaker height, angles, and listening distance before hooking it up. For casual listening, you can get away with pretty much anything really.

Take into account the speaker’s surroundings, its placement, and the materials it is placed on because these factors will also affect the sound.

Driver Size

The size of the speaker’s driver has a significant impact on the sound signature. Higher frequencies are handled by smaller drivers, whereas lower frequencies are replicated by larger drivers.

A speaker with multiple drivers (such as a woofer, midrange, and tweeter combination) will sound much “better” than one driver that tries to reproduce the entire frequency range. This factor is greatly influenced by the type of music you plan to listen to.

Speaker Construction

Another crucial factor to think about is speaker construction, as various materials can be used, each with different tonal characteristics that will influence the speaker’s sonic qualities.

It is important to note the differences between a speaker made from different plastics or woods and how this affects the sound. The construction of a speaker is a topic for another discussion.