In today's world of music production, it’s common for bedroom producers to send their self-made mixes to mastering engineers or upload them to automated mastering services for final polishing. Generations of musicians may change but newcomers continue to make the same mistakes when mixing down their tracks, a problem that’s only been exacerbated by having a significant portion of recordings come from home studios and personal computers.
These homemade mixes usually leave mastering engineers shaking their heads in frustration, rolling their eyes, and/or uttering various curses that are not suitable for reprinting here. The era of digital audio recording hasn't even existed that long but just about every experienced mastering engineer on Earth can probably compile a list of the most typical and widespread mistakes made during home mixing – issues that force them to seek ways to correct nearly irreparable mixes.
And, as for the online mastering services, while the neural networks running under their hoods don't know how to curse, they also aren't capable of saving mixes with major flaws.
So, in an effort to help engineers keep their heart rates lower, let’s take a look at the list of the most common mistakes in home mixing. Regardless of which method of mastering the creator of the mix chooses, these are the things they should try very hard to avoid.
It doesn't matter what style of music the bedroom producer works in—whether it’s EDM, rock, or trailer music—the most common issues with mixes are the same across the board.
The standard for music mastering specialists is 48 kHz/24 bit. If the project was originally set up at 44.1 kHz/24 bit, then that’s also fine. The format of an Audio CD (44.1 kHz/16 bit) is fine, too. The main thing is to maintain the bit depth and sampling rate used within the tracking/mixing project when preparing the stereo file of the mix (mixdown).
It's important to remember that when reducing the bitrate and sampling rate to 44.1 kHz/16 bit during the export of the stereo mix, quantization errors (not the type that aligns rhythms to the time grid in a DAW) introduce noise into the final file. Typically, mastering engineers handle this by applying dithering algorithms when rendering from higher resolution formats to the Audio CD format. Don't try to do their job for them.
But what if you followed the modern method and recorded and mixed at a sampling rate of 96 kHz or higher and a bit depth of 24 bits? Then it's better to output the stereo mix in 48 kHz/24 bit format. In this case, lowering the resolution does not add noticeable noise to the track.
Any plugins on the master bus other than, perhaps, level meters (sound pressure indicators, virtual VU meters, etc.) are off limits. Avoid using these even when bouncing the stereo mix. Measured? Confirmed there's no clipping and the mix volume doesn't exceed peaks of -6 or -5 dB? Disable the plugin. And of course, limiters, equalizers, maximizers, saturators, compressors—any devices that interfere with the mix sound—shouldn't be active on the master bus.
To be effective, a mastering engineer needs headroom. An ideal source for mastering is a recording where the peaks in the loudest and densest part do not exceed -6 dB. Engineers often accept levels as high as -3 dB. It sounds paradoxical, but making a mix louder is easier if the original is not compressed and was mixed with good headroom.
From the initial stage of tracking instruments and producing, it's essential to ensure that none of the project's tracks enter the "red zone" of distortions. Ideally, the faders on the virtual console should be initially set approximately to -10 dB.
We all strive for our music to sound impressive while we produce it. This can push us to make drums huge, bass especially deep and punchy, and melodic hooks vibrant and energetic. To achieve this, we might use saturation plugins that emulate the workings of various analog devices like tube preamps, mixing consoles, and so forth. And with their usage, there's always a risk of overdoing it.
It might seem strange, but mastering engineers prefer to receive "boring mixes." If a recording has a lot of distortion, such as tape saturation, nobody will be able to fix it. Everything done during mixing that sounds scratchy, too bright, roaring, or wheezing is irreversible. So, if you’re going to be doing any saturation of vocals, drums, or any other instruments in the track, it should be done very carefully.
We've already mentioned that compressors and limiters shouldn't be active on the master bus when bouncing the mix to a stereo file.
These tools narrow the dynamic range (simplified as the difference between the quietest and loudest sounds) of the recording. They also frequently cut attacks too aggressively, leaving little room for maneuvering for the mastering engineer. Dynamic range manipulation, including multiband compression—different in different frequency spectra—is still the domain of the mastering expert.
Despite knowing that no plugins should be active on the master bus, some producers will still manage to overcompress specific instruments within the mix, such as vocals or drums. This results in an unbalanced mix. In the mastering studio, it's often impossible to "uncompress" strongly flattened elements of the recording. This is something to keep in mind. Apply compression cautiously during mixing.
In other words, the mastering specialist doesn’t want to see any peak reductions that are characteristic of heavy compression and limiting in the submitted file. In certain genres like dubstep, metal, or trailer music, hard compression is moderately tolerated (but within reasonable limits). One mastering engineer put it like this:
Mastering engineers often encounter mixes where lead vocals, guitars, and synthesizers contain a lot of "high range" low frequencies around 500 Hz. This typically creates a tinny sound and a feeling of a "thin" mix. Sometimes, the mix may sound "boxy" if too many instruments hum around the 400 Hz frequency. While mixing, it's crucial to remember this and use cutoff filters for those frequency ranges that are ineffective for particular instruments. For example, guitars should generally stay above 100 Hz.
Another cause of the impression of a "thin" mix arises from poorly thought-out panning. For instance, two or four guitars or several synthesizers spread out to the extreme left and right positions. This creates a "big mono" effect in the recording, weakening its sound and restricting a mastering engineer's capabilities.
Additionally, it's important to note: if the Haas effect is applied to too many instruments during the mix creation process, this also transitions the mix into the "big mono" category, which, again, is not good for the mastering engineer.
Another extreme worth mentioning is placing most instruments close to the "center" of the recording when panning. Often, this mistake is paired with excessive use of stereo reverb, which, contrary to expectations, fails to salvage the mix. This is another one where you have to be careful when considering instrument placement on the virtual stage.
This is a really common issue. Tons of musicians these days will create their tracks wearing headphones (often consumer ones) and mix them there, or use hi-fi speakers instead of audio monitors for mixing. Equipment like this makes it extremely difficult to control the amount of bass and high frequencies in the recording.
Independent musicians, either accidentally or deliberately, can tend to load enormous amounts of boomy bass into the music. We’re talking the lowest—below 50 Hz. This "steals" the mix's volume, and it can only be corrected on mastering with considerable effort and not always successfully.
Similarly, high frequencies can suffer, too. In pursuit of crystal clear sound and airiness, musicians leave too much audio content in the band above roughly 7-10 kHz in the mix.
Some mastering engineers estimate, based on their observations, that about 50% of rock bands and 25% of rappers intentionally or unintentionally "hide" the vocal part, believing (sometimes correctly) that it was poorly performed or recorded. The outcome is usually predictable: neither an experienced professional in a mastering studio nor a regular listener can understand half of the lyrics in the mix.
In mastering, fixing this is almost impossible. Engineers will often advise musicians to play the song before sending it in for final processing and ask friends to repeat the lyrics they heard.
Forgot to use a de-esser during mixing? Then, during mastering, the singer's explosive hissing is going to come forward so strongly that it’ll become unbearable. The mastering engineer will struggle to remove all the "ssshh" sounds without damaging other instruments in the song. It’s a mess.
You might find it surprising, but mastering engineers often receive mixes or stems where instruments are played out of sync, reverberation decays and other spatial effects are truncated, clicks are audible at loop seams, and vocal artifacts like "spittle" remain uncleaned.
All these problems need to be solved not during mixing but during the production phase itself. These aren't just problems – they're failures that cannot fundamentally be fixed during mastering.
Often, mixing is done at medium or low volumes, leading musicians to miss out on some barely audible errors. Meanwhile, during mastering, all flaws that were previously unheard, masked, and undetected jump out at full scale for listeners.
A recording being prepared for submission to a mastering engineer should ideally be checked at high volume. Unpleasant surprises can emerge when you’re playing it back at 90-100 dB of physical sound pressure (loudness from speakers)—for instance, the mix might become insanely bright or reveal tons of sub-bass. All these issues should be addressed before the mastering stage.
Tracks sent to the mastering studio often turn out to be riddled with low-frequency rumble, high-frequency hiss, and other grime. Besides being unpleasant to hear, these elements "eat away" at headroom and "steal" volume.
These issues can arise for various reasons—say, street noise got mixed into a vocal recorded in an acoustically untreated room, or a high recording level was set for the microphone and the vocalist wasn't singing as much as whispering.
Tracks with noise need to either be re-recorded or an attempt needs to be made to filter out the noise during the mixing stage. Most often, noise can be detected in quiet parts of the track and at the beginning (sometimes at the end, if the arrangement features a long decay).
This is more of an arranging issue than a mixing one because mixing is also usually unable to effectively solve this. There’s one real solution here: the artist needs to select kick and bass sounds more carefully, considering the potential conflict ahead of time. Also advisable: create bass and kick parts, ensuring, where possible, that they don't interfere but complement each other.
Modern recording capabilities, accessible even in home studios, often push musicians and sound engineers to record everything imaginable with two mics—from acoustic guitars to vocals, from strings and flutes to electric and bass guitars (or record them with stereo mics). People often forget to check the resulting recordings for mono compatibility.
In this situation, the artist should either thoroughly test the results for mono compatibility during tracking or record all instruments in mono.
Okay, there you go. A collection of the most common mixing mistakes in home studios. Take this knowledge and convert it into a brief checklist that you can refer to in the future when making recordings and mixes so that you can avoid known pitfalls.
And just on a final side note, remember to respect the work of mastering engineers. No amount of payment can help them transform mixes containing technical defects into good-sounding tracks. Be understanding when a specialist tells you that the mix is not ready for final polishing and needs further work. They probably know what they’re talking about.
