A headphone amplifier is basically a small power amplifier. Which is specially invented for the small loudspeakers of headphones. It is a separate electronic device that increases the power (i.e. voltage and current) of the audio source unit.
Amplifying the signal is needed to attain sufficient power to drive the conduits of the speakers and enhance the sound system. This results in a superior more detailed audio resolution and a generally clearer musical sound.
Since headphones are usually operated with portable gadgets, most headphone amps are powered by batteries. Therefore, these can be easily carried or moved as well.
Because of the popularity of digital devices like mp3 player, iPod and iPad, smartphone, tablet and laptop, most headphone amps have built-in Digital to Analog Converters (DAC).
DACs in an amp are characterized by a USB port to connect directly with a digital gadget which also serves as its power source. As its name literally indicates, a Digital to Analogue Converter (DAC) will convert digital sound from your computer into an analog sound or original sound waves.
In our digital age, most headphones today are manufactured with built-in DACs to make them compatible with digital devices.
Thus, using a separate DAC device is mostly unnecessary.
Why do I need a headphone amp?
For sound and music aficionados, a headphone Amp is a necessity. Mainly is because they are very sensitive and particular against to sound quality. The sound quality produced by speakers with a headphone amp is way crispier and better.
However, for an average music listener, the need for a headphone amplifier could be far-fetched. As headphone amps may be costly, it would simply translate as an additional expense for them.
Because of this, it is fairly critical for you to understand what head amps can do. Including when what and why you would actually need one.
To put it simply, a headphone amp improves the sound quality of your headphone speakers. It improves it in the same way as an amplifier improves the sound quality of a component speaker.
And what exactly does that mean?
The first obvious change that you will notice in adding a headphone amp is the louder sound. The headphone amp intensifies the volume of a weak audio signal. This translates to greater volume intensity of sound energy which you can immediately perceive as being louder.
Improved tone quality
Some argue that a good tone is subjective. A tone pertains to the regularity of vibration which produces the sound. This concept is immediately encapsulated by the duration of the sound. Better tone quality is achieved when a sound is able to sustain its pitch, intensity, and timbre as it is needed in creating music.
Greater bass tone
One of the easiest ways to distinguish better sound quality is to focus on the bass tone. The base is the low or deep tone of a sound that sets the rhythmic and harmonic foundations of music. This is most conspicuous in electronic, pop and dance music because the bass beat is essentially what provokes people to move. Headphone amps improve the sound by intensifying the volume and compact depth of the bass.
Better sound clarity
Sound clarity refers to a lot of things to different people. Clarity can refer to the lucidity of distinguishing the different sounds or instruments simultaneously played in a music or song. It can also refer to the timbre where you can distinguish the different musical notes used in producing the sound of music.
In both instances, a headphone amp helps you enjoy every single instrument and note in music. It also better appreciates the artistry behind its production.
Upon hearing clearer music, you would suddenly realize that you haven’t heard that parts of music before. You will hear instrumentations and notes which are imperceptible in ordinary speakers unless you would listen closely. And this is just one of the enhancements that an amp is capable to do.
Most gadgets have built-in amps; why would I need a separate one?
Most modern music playing devices have built-in amps. Most tablets, smartphones and CD players do. Thus, it seems redundant if not pointless to purchase a separate external headphone amp.
In a nutshell, a separate headphone amp simply produces better amplification and better sound.
Built-in amps are music players and headphones have limited power, precisely because manufacturers need to work on a limited area to incorporate the built-in amp.
A separate headphone amp allows for more dedicated space for developing. Thus superior integrated circuit systems and a stronger power produce generally improved sound.
A stand-alone amp has the capacity to generate greater power for the headphone speaker. This is to prevent sound distortion at audio peaks. The headphone amp is not intended to rave-up your ears with deafening sound.
It is intended to provide cleaner, clearer, purer and sharper sound regardless of the volume of sound.
Although you can appreciate or hear this better in louder sounds. It is always advisable that you maintain a comfortable volume level, especially when listening through a headphone.
When will my headphones need a headphone amp?
A headphone amp is not a fundamental need when it comes to purchasing a sound system. But for a musical enthusiast, it is necessary because the sound quality will be enhanced by a headphone amp.
A good headphone is a lot more important when setting up a personal audio system for obvious reasons. It contains the speaker through which we listen or hear the sound. It goes without saying that a headphone amp is only secondary.
Thus, choosing between buying a good headphone or a headphone amp is not really a dilemma as the headphone is top priority.
You will definitely need a headphone amp if your headphone has no built-in amp. Adding an amplifier will greatly improve your headphone speakers. The amp will help the headphone in reaching its full potential. You will hear a perceptible change immediately in terms of sound volume in using an amp.
On the other hand, adding a headphone amp even if your headphones have a built-in amp is optional. Nevertheless, an amp will always enrich and improve the sound. In which case, you can perceive a crispier sound of music when adding the headphone amp.
A headphone amp is specifically suitable to over ear headphones with high impedance ear covers.
This type of headphone requires greater voltage to reach that optimal listening level. Portable music players such as mp3 players, smartphones, and tablets have limited voltage because they mainly rely on their internal batteries.
The amp functions as a supplement to provide the required power. Thus it drives your headphones to its full potential that translates to clearer, more detailed and dynamic sound.
When would I NOT need a headphone amp?
The typical earphones that come with your smartphones and gadgets are normally in their most optimal level when used with the said musical players. Thus they are especially efficient and may not necessitate a headphone amp.
The built-in amps in your portable musical devices are compatible and sufficient to enable the earphones to attain their full potential.
If you are using an earphone, you don’t need a headphone amp.
Not all over-ear headphones can benefit from a headphone amp. Over-ear headphones with Noise Cancelling features do not need a separate headphone amp. This would not provide a substantial benefit to sound output when applied.
This type of headphones usually comes with a built-in amp. Additionally, it has its own power source to neutralize or reduce noises from the external environment.
What should I look for in a headphone amplifier?
Also known as source impedance, output impedance pertains to the static resistance or the inherent opposition to the flow of electric current and dynamic reactance or the opposition caused by changes in voltage in the electrical source.
The output impedance of most headphone amps is between 0.5 – 50 Ohms. When it comes to amps, it does not follow that higher output impedance is better. In fact, high output impedance may cause unstable fluctuations in frequency response.
Instead, to ensure optimal performance, the impedance output of the amplifier should match or complement the impedance output of your headphone.
If the headphone impedance is high, the power delivered to it will be decreased. If low, the high power delivered can cause power overload which will damage your amp.
Matching the impedance of your headphone and amps is the most important aspect in choosing an amplifier.
This does not mean that your headphones and headphone amp have equal ohm (Ω) rating. One of the simplest ways to match impedance is to pair a headphone that has at least 10 times ohm Ω value of your headphone amp. For instance, a 50-ohm headphone amp matches well with a 500-ohm headphone.
This refers to the ability of the amp to regulate an unwanted movement of the speaker cone, especially in low frequencies.
It serves as a solution for mismatched headphone and amp, in which the amp has a dynamic driver that controls the oscillation needed to ensure precise sound reproduction and prevent compromising sound quality.
The bigger the mismatch between the impedance of the headphone and amp, the bigger the electrical damping will be.
Substandard damping is especially perceptible in the reproduction of low-frequency sounds in which the bass becomes damp or sodden.
In addition to output impedance and damping, there are other factors to consider when choosing a headphone amp. Note however that these factors are usually addressed by matching output impedance and improving damping factor.
This refers to the electrical power from your amp to your headphone, which in turn determines the sound power generated.
In layman’s term, this basically pertains to how loud you can play your music. Note however that when applying to headphone amps, you should be careful in maintaining volume at a level that will not damage your ears.
The output power of an amp is restricted by voltage, current, and temperature.
The first checks the highest amplitude of the waveform it can produce. This regulates the uttermost momentary power generated for a specified load resistance.
The second determines that lowest load resistance that a headphone amp can propel at its maximum voltage to prevent damage.
Finally, the temperature is controlled by the quality of materials used by the amp. An amp that immediately heats up or has no mechanism to cool down will most likely get damaged if used for a prolonged period of time.
Total harmonic distortion
This measures how faithful your amp is able to replicate the input signal perfectly as an output. Any change or dissimilarity in waveform between the input and output is described as distorted.
This refers to the ability of the amp to play the bass, middle, and treble or high tones precisely and in proportionate levels. Frequency response is critical maintaining the original sound recording.
This pertains to the ability of the amp to combine or integrate several signals. Thus reducing unwanted frequencies which cause interference or noise in sound quality.
What are the different types of headphone amps?
Basic Headphone Amps
This is the type of headphone amps that are customarily used at home or in music studios. It is basic because of its simple design and functionality.
They often consist of a headphone jack and volume control. This headphone amp usually has an AC adapter which you plug into an electrical outlet as a power source.
Headphone Amps with DAC
Many headphone amps now come with a DAC (Digital to Analogue Converter) which is characterized by a USB port.
With the prevalence of digital music, its inclusion in musical gears has become a standard operating procedure. People listen to music through their computers or laptops.
As mentioned earlier, a headphone amp with a DAC is mostly unnecessary. Because digital music players like computers usually have their own built-in DAC. However, not all DACs are the same. Most built-in soundcards in computers are off low quality.
That being the case, having a headphone amp with a DAC will basically sidestep the soundcard of your PC and use the DAC of the amp. In this way, better sounding music is produced when listening from your computer to your headphone.
Portable Headphone Amps
With the recent trend of listening to music with portable players, many headphone amps are also made portable.
A portable headphone amp is basically an amp which is operated by a replaceable or rechargeable battery. Some have Bluetooth capability so that you wirelessly connect your headphone to the amp.
What’s the difference between tube and solid state headphone amp?
Amplifiers, in general, can also be classified as a tube amp and solid state amp. The former has long been the principal type of making and relishing sound. In this modern age, however, solid state amps have dethroned tubes as the standard amp of choice.
The basic difference between the two lies in its components. However, they basically follow the same principle in amplifying sound.
Tube headphone amps utilize vacuum tubes to strengthen audio signal and power. It involves complex operating mechanisms such as transformers, resistors, heaters or filament, among others that require regular maintenance.
The valves and vacuum caps are subject to wear and tear and must be replaced time and time again. Because of these, most tube amplifiers are more expensive. This is especially true for old amplifiers whose spare components are rare which makes them even more costly.
A solid state amp on the other hand use transistors and a semiconductor device. The latter converts small input signals to higher output signals to amplify them. Incidentally, this can also be used as a switch.
The electrical structure of transistors is straightforward and simpler. It also uses fewer and lighter components (e.g. smaller transformers) which makes it more compact and portable.
This amp is also cheaper because they do not require much maintenance. A major trend in technology is to make things lighter, smaller and more portable.
This makes a solid state amp the preferable choice.
The downside of it is the mass production of transistors which paved the way for substandard amps that use low quality wiring and parts.
Should I buy a tube or a solid-state headphone amp?
It depends. As to which type of amplifier sounds better remains debatable.
Tube headphone amps are especially appealing for conservative listeners.
Accordingly, tube amps are faithful in producing the genuine sound of music that resonates their specific era or generation. They are compatible with analog recordings as they produce a more flavorful roundedness in sound a transistor is unable to replicate this.
Moreover, they give an elevated dynamic range that gives overdriven audio a unique charm to listeners.
Solid state amps are more preferable to progressive listeners.
For one, it easily suits most modern devices. Secondly, it fits well in different music genres especially contemporary music.
Finally, they are not as finicky when it comes to speaker matching unlike tube amps which are demanding if not intolerant about mismatches.
Thus, it would be more convenient and easy for a music lover to use it without necessarily having a deep technical proficiency in setting up sound systems.