If you've spent any decent amount of money on a pair of in-ear headphones or full-size cans and then decided to Google them, you've no doubt stumbled across forum pages or reviews of headphone amplifiers. This can, for many, be the first step down the rabbit hole that is "audiphile grade" equipment. If you're looking to maybe spend a tax rebate or some birthday money (or you're just rich, of course) on a quality pair of headphones or in-ear headphones, then you've probably spent a lot of time on the internet. This has probably landed you in forum posts about how you really need to "amp those headphones to get the most out of them" and that "your smartphone just isn't going to cut it". There's a lot of misinformation and a lot of opinions out there on the Internet and I'm going to try and explain just what a headphone amplifier is and whether or not it makes a genuine difference.
What is a Headphone Amp and Why Should I Care?
First of all, let's cover what a headphone amplifier is. Basically, a headphone amp does exactly what you think it does; it amplifies the left and right stereo signals that go to your headphones. Our smartphones and tablets all have one, the problem is they're just not that powerful. Why would they be? Battery life is at a premium and our smartphones aren't high-end audio gear; they're smartphones. A portable headphone amplifier is the term given to an external amplifier that has its own battery and a few controls on it. These take the analogue stereo signal from your smartphone or tablet and then further amplify it through a set of signal processors and amplifiers. The result is a signal that has more power to it and will ultimately reach higher volumes, but more importantly amplify the signal and therefore improve the overall quality of your sound.
So, why should you care? Well, if you're spending say $20 to $50 on earphones or headphones then ultimately, you don't need to care. There's little that can be done to improve a pair of headphones that aren't very good in the first place. Now, if you were to spend $100 or more on a pair of earphones or headphones, then you should care. An external amplifier will generally help make the most of your new purchase. There are couple of key things that headphone amps can help with; soundstage and separation. Soundstage, in brief, refers to how far away instruments and vocals sound. A wider soundstage would be be described with guitars sounding further away and not so close to your eardrum. Separation refers to how easy it is to tell certain instruments apart from each other; for instance an amp with good separation would make it easier to determine which guitar is a six-string and which is a bass guitar in the mix. Together, these two improvements can help 'open up' your music. It's hard to explain but an amp can help take away that "cloth ear" feeling and deliver a sound that feels less like a performance is happening very close to your ears, but rather all around you. As a result, your songs will open up and you'll hear parts in the mix you didn't before and pick up on subtleties that you would have otherwise missed. This is why you should care.
Okay, But do I really Need One?
Ultimately, this whole question comes down to "it depends". It depends on what type of listener you are. Casual listeners that maybe pop one ear in at all times just for some noise need not apply, but those that really want to make the most out of their music and are passionate about their favorite artists and albums should definitely consider it. A decent portable headphone amp can be purchased for as low as $40 these days, like this Topping NX1 and you can spend as much as you like from there on, up into the hundred of dollars if you really want to. A necessity a headphone amp isn't, in my opinion it all depends on what you want from your listening experience. If you're the type of listener that sits - or stands! - at a desk all day and listens to music to focus better or drown out other noises, then a headphone amp could be well suited for that environment. The same goes for those that travel a lot and spend hours on aeroplanes and in hotel rooms, a portable amp is a great way of getting a better sound without taking your speakers with you.
I've been using a portable amp for a long time now, my personal favorite being the affordable FiiO E11K, and it definitely makes a difference with quality earphones like the RHA T10. Do I use it all the time? No, I very rarely use it while on the move because it's not all that convenient, however when I'm listening to music in bed or at my desk, an amp really brings out the best in my music. Do I feel like I need one? No, not really, but it's definitely a nice luxury to have and I genuinely hear a difference.