So, should you be mixing with headphones or monitors? You should be mixing with both. Headphones have many advantages over monitors, and monitors have many advantages over headphones. It is possible to mix with either one, to some degree, but to mix with both will undoubtedly yield the best results.

Generally, headphones are good to work on the details of individual tracks and for non-critical mixing tasks like track organisation, track importing, and workflow. Monitors are good to work on sets of tracks, the whole mix, and critical mixing tasks. The essence of mixing is to ensure that each instrument is clear and has its own space.

Table 1 below indicates where headphones or monitors may be used during the mixing process.

	Headphones	Monitors
Songwriting	Yes	Yes
Composing	Yes	Yes
Midi Programming	Yes	Yes
Song Structuring	Yes	Yes
Stereo Width	Reference	Primary
Mix Dynamics	Reference	Primary
Track Dynamics	Primary	Secondary
Frequency Problems	Primary	Secondary
Pops and Clicks	Primary	Secondary
Tuning	Primary	Secondary
Unwanted Artefacts	Primary	Secondary
Low-End Mixing	Primary	Secondary
Mid Range Mixing	Reference	Primary
High Range Mixing	Reference	Primary
Panning	Reference	Primary

Table 1: Mixing with Headphones versus Monitors

Using headphones for songwriting isn't precisely 'mixing', but headphones are beneficial when writing midi, composing, and establishing a song structure (i.e. song introduction, verses, choruses and ending). Using headphones for production is also useful when editing down, muting, fades, and adding cross-fades.

Using Headphones For Detailed Work

You can see in Table 1 above that headphones should primarily be used for individual tracks and low end mixing decisions. Monitors can be used in all cases; however, they will not always provide optimum results in a budget home studio. Additionally, headphones can help to keep your mind focused, especially when there are a lot of recorded tracks to check.

Headphones Are Extremely Practical for Home Studios

In a Home Music Studio, headphones are simply more practical:

• When you don’t want to disturb others
• When you don’t want others to disturb you
• When you are at a coffee shop or waiting for a flight
• Late at night
• Early in the morning
• When you don’t have a dedicated space to work

The Drawbacks of Headphones

Accuracy

Although headphones are highly practical, there are a few drawbacks when mixing exclusively with headphones. Most headphones can’t reproduce low frequencies which means that sometimes the bass and kick will be too emphasised or mixes will simply be too muddy. It is also possible to cut too much EQ, and undercook reverbs and delays as these are often more apparent when listening in headphones.

Cross-feed

Cross-feed, also known as cross-bleed or acoustic stimulation, is the behaviour of sound waves leaving monitors and arriving at our ears. A human's right ear will pick up sounds from the right before the left ear because it is closer. The left ear will pick up (almost) the same sound a fraction of a second later. Our brains process information from both ears to determine spatial information.

While listening on most headphones cross-feed of audio is zero, and therefore it can be challenging to evaluate the spatial information needed for acceptable stereo imaging. Using headphones limits our judgement for how far away something is, ambience, and depth.

Stereo Imaging

Perhaps one of the most challenging details to judge while mixing in headphones is the stereo image. Listening on headphones tends to make audio sound wider compared to monitors. The stereo image on headphones also makes the sound appear as if it is coming from inside your head. This is very different compared to listening to studio monitors or regular speakers. If you are mixing with headphones, consider panning in an additional 10-20% of your original stereo width decision. You may also want to pay close attention to the wetness of reverb and delay.

Why Do Pro Mixing Studios Use Nearfield Monitors?

Nearfield monitors are ideal for all music studios due to their cost, size, and their ability to reproduce recorded audio accurately. Manufacturers design nearfield monitors to be listened in close proximity with extremely flat frequency responses.

Flat Response

One of the main objects of mixing is to create audio with a well-defined frequency range. To establish and define which frequencies sound good mix engineers rely on their ears, and equipment that “faithfully” reproduces audio frequencies.

The holy grail of faithful reproduction is a system that can provide a flat response. For example, speakers that don’t add 100Hz where there was none or attenuate everything over 8kHz where they shouldn’t.

A flat response refers to the graph of measured results for a particular sound system where the curve is literally “flat”. Figure 1 shows the frequency response curve for Yamaha’s MSP7 Studio monitors. You can see that apart from the small bump to the left of 100Hz, the curve is flat - flat enough for mixing anyway!

Figure 1: Yamaha MSP7 Studio Monitors Frequency Response

The frequency response curve shows that frequencies below 70Hz roll-off steeply. You can ignore the greyed-out part of the graph, below 50Hz, as this is outside the range of normal human hearing. And, bear in mind that the x-axis is logarithmic.

If you were mixing with these monitors, you may be well advised to take care with the decision making of low-end instruments like the kick drum and bass guitar.

The Room

Monitors alone are not the complete solution to getting a great mix. An equally important factor is the room where the monitors are located. Rooms can take a perfectly fine flat frequency response of a pair of studio monitors and bump the low range, accentuate the high frequencies, and play all kinds of games with reflected sounds.

These room problems are why acoustic treatments are often installed in studios. Diffusers for high frequencies and bass traps for low frequencies help to control the room’s acoustics.

Mixing with headphones removes many issues associated with room acoustics and can be useful, but unfortunately, headphones are not the answer to all mixing woes. Take a quick look at the frequency response curves for the five sets of headphones and one set of earbuds below (figures 2 to 7). You will see that none of the curves come close to the frequency response of the studio monitors.

	Studio Quality	Regular
Sennheiser HD800	⬤
Beyerdynamic DT770 Pro	⬤
AKG K240	⬤
Bose Quiet Comfort II		⬤
Skullcandy Hesh 2		⬤
Samsung Galaxy Earbuds		⬤

Table 2: The Headphone Mix

Three pairs of headphones are studio quality, and three pairs of headphones are regular quality.

Keep an eye on the dotted blue line at 0dB - that is the flat response target.

Figure 2: Sennheiser HD800 Headphone Frequency Response

The HD800s lack a flat response between 50Hz and 105Hz, although mixing the low end with these headphones is usually not a problem. You can see a slight bump at 1kHz, after which response is flat-ish between 1.5kHz and 4kHz. The high frequencies, according to the graph, could be problematic. There is another bump around 7.5kHz and a steep roll-off after that.

Figure 3: Beyerdynamic DT770 Pro Headphone Frequency Response

Ignoring the slight bump at 120Hz, and the dip at 200Hz, the DT770’s frequency response is relatively flat up to 2.5kHz. The remainder of the curve peaks and troughs, above 3kHz, but overall emphasises higher frequencies. To mix with these headphones, you would need to be a little careful not to boost high frequencies too much.

Figure 4: AKG K240 Headphone Frequency Response

In figure 4, the AKG K240 frequency response has a steep roll-off before 150Hz and a roll-off up to 1kHz. These headphones are likely to colour your mix in the high-bass range. In this case, you would be wise to look out for problems such as, under-emphasis of drum “body”, bass guitar overtones, and the “body” of electric or acoustic guitars. The remainder of the curve also illustrates potential problems with instruments sitting in the treble-range-frequencies.

Figure 5: Bose Quiet Comfort II Headphone Frequency Response

Figure 6: Skullcandy Hesh 2 Headphone Frequency Response

We will leave it to you to examine the frequency response curves for the Bose and Skullcandy headphones. It should now be easy to recognise the coloration that headphones add to audio. Headphone manufacturers, of course, build this into the design as it is this coloration which makes their product more attractive for a typical listener. Having access to a few pairs of “colourful” headphones is very useful to check your work as a mixer.

Figure 7: Samsung Galaxy Earbuds Frequency Response

The final frequency response curve that we are looking at belongs to Samsung's Galaxy Earbuds. The curve is the flattest of all that have been reviewed so far. We don’t recommend making important mixing decisions using in-ear monitoring. However, these look like a great addition to a headphone reference arsenal.

Know Your Equipment

Whether you are using headphones or monitors for mixing, your equipment will always, in some way, colour the sound that you hear. Mix decisions are made with our ears, so the trick is to know how your equipment will affect your mix. For example, if the bass response is not good on headphones, you will tend to exaggerate those frequencies that make your audio sound good on headphones and overcompensate the lower frequencies. Knowing how the equipment that you use for mixing sounds is therefore vital.

Getting 80% of the Way there on Headphones

Let’s assume that 100% of your mixing activities will be done on headphones. We will also assume that you have figured out the colourful characteristics of your headphones and have made appropriate mixing decisions. Your mix is probably as good as you will get it and is likely already 80% of the way there. In that case, you may consider passing your mix onto another mixing engineer, or even passing it on to the mastering engineer for finalisation.

You could at least try this on a few mixes to start with and compare what the other engineer does, against your original mix. Future mixes can then be tweaked with this knowledge, and you can be pretty confident with your work.

Referencing is Good Practice

As a general rule, try to listen to your mixes in as many different environments as possible. If you have a second set of studio monitors, listen on those. If you have a home hi-fi system or a small set of computer speakers, listen on those. Go out to your car and play your mix there.

The same logic works for headphones. If you have regular over-ear headphones or high-end studio headphones, listen on those. If you have a pair of noise-cancelling headphones or a pair of earbuds, listen on those.

Don’t stop there. Listen to your favorite music and reference tracks on headphones and monitors. Try to identify the differences you hear with one track being played on all of your pieces of equipment.

Listen on as many devices, and as many environments as possible, and to as much music as possible. Your mixes will benefit greatly!