Headphones have a unique way of colouring the sound they reproduce. This affects the way we perceive frequencies and ultimately how we mix. Most headphones have an extreme frequency response. It is pretty common to see a rating of 5 Hz – 35 kHz, even though human ears aren’t capable of hearing that far up or down. What you will hear, however, is an openness you wouldn’t otherwise get with a narrower frequency range. Again, this is something that has the potential to make or break a mix if you’re compensating or making choices that won’t translate well to other speakers. 

 Another common challenge presented by mixing with headphones is stereo imaging. Headphones sound wider than monitors, so you will need to mix narrower than usual. The left and right channels are sitting on each side of our head. Centre-panned mix elements sound like they’re out in front of us on a pair of monitors, while they sound like they’re in between our ears on headphones. 

Another factor to consider when you are thinking of mixing with headphones is crossfeed. When you’re listening to playback on a pair of monitors, the left ear perceives the left speaker and the right ear perceives the right speaker. A split second later, each ear hears the opposite speaker at a slightly lower volume. Our brain processes all of this in microseconds without any consideration on our part because it’s the natural way our ears have evolved. When we mix with headphones, crossfeed does not exist. 

The left ear hears the left channel and the right ear hears the right channel with no natural blending of the two. Our brain notices that something is missing and we have a tendency to dislike what we hear. This is another challenge that mixing with headphones presents. You can combat the lack of crossfeed by using open-back headphones instead of closed-back ones. Openback headphones have less isolation which means they allow a bit more sound to leak out of one side and into the other. This restores some of the naturalness we are used to. Some artificial crossfeed plugins, artificially insert some of the signals into the opposite channel. This is not an ultimate solution but it makes a difference.

Now let us take a look at studio monitors and how they fare. They perform their best in rooms that are acoustically treated. If you want to make the most of your monitors, make sure that you have at least treated the reflection points in your space. This will help minimize standing waves and early reflections that can blur and otherwise neutral response from your speakers. Monitors in an untreated space are not an honest representation of your mix. Before you buy expensive monitors, make sure that you will be using them in a treated space.

When it comes to listening levels, you need to listen to flat but not quiet levels. It is better to monitor around 85dB SPL. The science behind the way humans hear has determined that, at 85 dB SPL, our ears’ frequency response is pretty flat. At even higher volumes, the curve flattens out even more, but the potential for injury is much greater. The size of the room will also come into the equation when it comes to using studio monitors. One of the worst mistakes you can make, in addition to mixing in an untreated room, is to mix with monitors that are simply too big for the room. 5-inch speakers are a great bet for small rooms. It all depends on the size of your studio. 

Pitting one against the other, mixing on both studio monitors and headphones is better. It does not negate the great qualities you get on one or the other, however, the best option is to use a combination of both.

 Most headphone mixes do not have a lot of depth and they wind up being pretty loud. If this is the type of sound you are going for then perhaps you need to mix on both. It is not a good idea to mix solely on headphones. Studi monitors are much more demanding than headphones and this can come off as a downside. They require an adequate room and are best in an acoustically treated environment being pushed at plenty of dB SPL.