A lot of people started to care about “high resolution” digital audio when Apple launched its upgraded music service to the masses. Call that the “Apple effect,” as infuriating as it may be, but the iPhone maker isn’t the only one in the hi-res audio game: Qobuz, Tidal and Deezer have been doing it for a while, and Spotify has been toying with releasing its own version for a while. However, as many were quick to point out, some of Apple’s own products don’t necessarily support the higher sample rate and bit-depths on offer. No worries, there’s a dongle for that, and there are options for Android and desktop, too. We’ve tested dozens of these devices and the best DACs listed in this guide will play nice with any of the aforementioned services (aside from Tidal's MQA, which is a little more specific).

What is a DAC?

James Trew / Engadget

A digital-to-analog converter takes the digital (D) music from your phone or computer and converts (C) it into analog (A) sound you can hear. All phones and PCs have them, but since handsets moved to USB-C, Lightning or Bluetooth for music, the task of converting that signal was generally outsourced to either your adapter or your wireless headphones.

DACs can be used with phones, laptops and desktops but tend to be much simpler than a regular external audio interface. One basic distinction is that DACs are usually for listening only whereas an audio interface might have ports to plug in microphones and instruments (but an external audio interface is also technically a DAC).

The best DACs tend to be lightweight, making them more suitable for mobile use, although it still gets a little tricky with the iPhone as you still might need to add another dongle to make it play nice with Lightning. Also, not all DACs support all the higher audio resolutions. Most standalone DACs require external power or an onboard battery, though some can use the power from whatever you plug them into — in which case expect a hit to your battery life.

Why do I need new hardware to listen to music?

Apple

The short answer is, you don’t. You can play “hi-res” audio files on most phones and PCs, you just might not be getting the full experience. If your device’s audio interface tops out at 44.1 or 48kHz (which is fairly common and covers the vast majority of music online) then that’s the experience you’ll get. If you want to enjoy better sounding music at a higher sample rate and bit-depth (aka resolution), you’ll need an interface that supports it and wired headphones.

It’s worth pointing out that “lossless” and “hi-res” are related terms, but not the same thing and will vary from service to service. Apple uses ALAC encoding which is compressed, but without “loss” to the quality (unlike the ubiquitous .aac or .mp3 file formats). CDs were generally mastered to at least 16-bit / 44.1kHz which is the benchmark that Apple is using for its definition of lossless. In audio circles, a general consensus is that hi-res is anything with a sample rate above 44.1kHz. Increasingly, though, the term is being used for anything 96kHz and above.

This, of course, isn’t only about Apple’s new streaming formats. External DACs and audio interfaces are a great way to get the best sound and upgrade your listening experience generally. Especially if you want to get into the world of more exotic (read: pricey) headphones, as they often even require a DAC to provide enough clean digital signal to drive them. For audiophile headphones, a phone or laptop’s internal sound chipset often doesn’t have the oomph needed to deliver a hi-fi experience.

Okay, but can’t I just use the headphone adapter for my phone?

No. Well, yes, but see above. A Lightning or USB-C to 3.5mm headphone adapter often is an audio interface and most of the ones you’re buying for $7 (or that come free in the box) do not support hi-res audio beyond 48kHz / 24-bit. Android is a little more complicated, as some adapters are “passive” and really just connect you to the phone’s internal DAC like old school headphones. Others (active ones) have a DAC built-in and good luck finding out what your specific phone and the in-box adapter delivers. (Hint: connect it to a PC and see if it comes up as an audio interface. You might find some details there if it does).

What about Bluetooth headphones?

Chances are that over the last few years you’ve migrated from wired to wireless headphones (thanks, Apple). The world of Bluetooth headphones changes things a little when it comes to seeking better audio performance. What matters here is twofold, the headphones you’re using (as those will technically be the “DAC”) and the codec — the method used to send the musical data over to the headphones. It’s worth checking to see if your headphones support aptX and which version — aptX HD, aptX Adaptive are better than standard and becoming more common. Other systems exist, like Sony’s LDAC, but Qualcomm’s AptX has wider support thanks to its prevalence in Android devices.