Recording and Mixing Levels Demystified

I run a weekly music chat on Twitter called the DIY Music Chat. I’ve had several questions recently about levels when recording, mixing, and mastering, and even though I’ve been doing this stuff for nearly a decade, I only recently just finished sorting through all of the conflicting information myself. So I wanted to put it all down in an easily digestible article for everyone’s reference.

What I’ve found is that there are two main reasons for the confusion about signal levels: 1) the difference between analog and digital standards and practices; and 2) the fact that a lot of people use the same words for different things. For instance, the word “level” itself. Are we talking about peaks or average? And you can’t have a conversation about decibels (dB) without knowing whether you’re talking about dBu (aka dBv, dBVU, or Voltage Units, the analog standard) or dBFS (Full Scale, the digital standard). Let’s sort some of this out as quickly and simply as possible, in terms a home recording artist can understand and use.

(For the impatient – if you just want the bottom line info, you can skip to the end of the article.)

Analog vs Digital

In the analog world, the dB scale used is in Voltage Units, and is referred to as dBv, dBu, or even dBVU, since the meter is called a VU meter. It is a measurement of signal voltage, not of sound. 0 is the nominal ceiling, but most analog equipment such as amps, consoles, and tape drives sound better when overdriven — they get a natural distortion and compression from the equipment. Many analog modeling digital plugins also like to be overdriven to a point, to get some of that musical noise effect. Read the plugin manuals to find out how this works in your plugins. To further complicate this, there are two real world voltage standards for calibrating the 0 point: +4 for studio-level equipment and -10 for consumer-level equipment. Not to mention that analog modeling plugins will have VU meters that read differently from your DAW’s built in meters.

In the digital world of our DAWs, the scale used is dBFS, which means dB Full Scale. There is no going past 0*. It is a real limit based on the limitation of digital data, and hitting that ceiling causes clipping, which means the peaks of your signal are abruptly squared off, resulting in nasty sounding digital distortion. The level meters in the channel strips of our DAWs are primarily peak dBFS meters. If the levels are getting into that little red area at the top, they are too hot.

Clipping meter

Clipping Meter & Clipped Waveform

Levels in General

When people talk about levels, they’re usually talking about peak levels. It’s the peaks that are the concern when it comes to the recording and mixing process, as you need to make sure they’re not clipping. When you get to mastering, you start to talk more about average or RMS level, because that is where our perceived loudness comes from. There is even a relatively new unit scale called LUFS for Loudness Unit Full Scale that is meant to standardize the measurement of broadcast sound across different systems in a way that is more like how we actually perceive loudness. If your DAW does not meter in LUFS (like the new MultiMeter in Logic Pro X), you can add a plugin that does.

Mixing and Summing

Just because your individual tracks aren’t clipping doesn’t mean they won’t join together and clip at your output bus (aka 2-buss). In fact, it’s more than likely that they will, even if they’re only moderately hot signals. The best practice is to route your tracks into groups, and then use those groups to level your final output signal to your 2-buss so that you have finer control over your signal summing. Watch the meters and plugins on each track, each group, and your output bus and make sure that none of them are clipping. This process is called gain staging.

Mixing and Pan Law

To twist this just a bit, there is something called the “pan law.” A signal drops by 3 dB as you pan it to one side or the other. If you listen your mix in mono, and you should, you will hear this as the sides drop away slightly and the center gets louder. This is a good check to see how your mix will hold up in different circumstances. Some DAWS have a setting to compensate for this.

Definition of Terms

Clipping – when the signal waveform hits the ceiling (0 dbFS) and gets cut or squared off, resulting in nasty digital distortion.
DAW – Digital Audio Workstation, the software application you use to record/mix/master, such as ProTools, Logic Pro, or Abelton Live.
dBv/dBu/dBVU – decibel scale in Voltage Units, the standard for analog audio gear. 0 dBv = -18 dBFS.
dBFS – decibel scale as Full Scale with 0 being the true upper limit, standard for digital. -18 dBFS = 0 dBv.
Dithering – adding noise to smooth out the intersample steps when downsampling (going from 24 to 16 bit, for instance).
Dynamic Range – the difference between peak and RMS level in a track. -10 to -15 is good dynamic range for a mastered song in most genres.
Gain Staging – controlling input and output all along the signal chain to maintain proper levels.
Level (peak) – the peak level of a signal, meaning the highest/loudest point reached.
Level (RMS) – Root Mean Square or average level. This level is the perceived loudness.
Limiter – a software plugin that acts as a ceiling to keep the signal from hitting the real ceiling. Used in mastering to add level to a track while preventing clipping.
LUFS – a new scale in Loudness Units.
Signal to Noise – ratio of signal (your recording input) to noise floor (hiss, hum, room noise). This is a big issue in analog recording but not very much in digital recording.
Track – can refer to an individual track in a DAW or to a song, but usually a track on a channel strip. An exported single track is called a stem.

Best Practices

The following notes are based on industry standards, research, and my own personal experience. YMMV, but to be honest, you aren’t going to go wrong following the guidelines below.

Recording
Recording, aka “tracking”, is basically bringing analog signal into a digital workstation. You have level controls at the instrument, the interface, the track, and the track plugins, and you should pay attention to all of them. Get your levels properly set before hitting record.

  • Record at 24 bit if you can, but no less than 16 bit. You will get plenty of headroom either way.
  • When recording/tracking, keep peaks between -15 and -6 dBFS for good signal to noise ratio. You will hear people say -18 or even -20, but in my experience, an average of -10 to -8 peaks on recorded tracks is a good signal and anything less than -15 frankly doesn’t have good dynamic range.
  • Remember to record mono (single microphone) signals like vocals or guitar onto mono tracks.

Mixing
Mixing is the art and craft of balancing and enhancing your individually recorded tracks into a cohesive song. The better recorded your tracks, the easier it is to mix them.

  • The best starting point for mixing is to level all of your tracks with a gain/trim/channel strip plugin to get all of your tracks peaking around 0 dBv or -18 dBFS. At that point, you can begin your fader adjustments for balance.

    Level Trim Examples

    Initial Track Output Leveling

  • Take the pan law into account and know that your panned signals will be perceived as -3dB less EACH than they would be if they were in the center. Check in mono.
  • EQ and compression will affect your output levels. Keep an eye on your levels when using them, particularly with the makeup gain on compressors.
  • Your final output mix to send to mastering should be peaking at no more than -3 dBFS. -6 is preferred by mastering engineers, to give them room for EQ/compression/limiting. It’s perfectly fine (and perhaps recommended) to mix into some compression, but leave limiting to the mastering engineer. Do not crush your mixes.

    Waveform Examples

    Too Hot, Too Cold, Just Right

  • Your final output mix should be at least 16 bit. 24 bit is recommended.
  • Joint/interleaved stereo WAV is the standard file format.

Mastering
Mastering is the final EQ & level adjustment to bring your tracks to commercial quality sound. Ideally this is done in a sonically controlled environment by someone other than the mixer.

When I started learning mastering, I heard that the standard practice is to set your hard limit at -.1 dBFS, or even -.3 dBFS, to allow a “little room for overs” when bouncing or translating between formats. I only recently found out that if you are bouncing to MP3, which everyone is, you should actually be setting an upper limit of -.5 or even -.7 dbFS because of the extra processing to compress the song into a lossy format.

  • Set your limiter ceiling to -.5.
  • The recommended RMS or LUFS for a mastered track depends on the genre, so check against your reference track. Generally stick to the -10 to -12 RMS/LUFS range. Note that with your ceiling close to 0, a -10 RMS/LUFS translates to 10dB of effective Dynamic Range.
  • The more you shrink the Dynamic Range, the more compressed and distorted your track will sound.
  • The standard format for a mastered track is 16bit/44100Hz, which is the CD standard. The Mastered for iTunes standard prefers 24bit/44100Hz.
  • If you downsample from 32 or 24 bit to 24 or 16, you should dither the WAV with MBIT or Type 2 noise shaping.
  • You can check for intersample clips with Apple’s Mastered for iTunes. Check a bounced MP3 as well as the WAV file.

Bottom Line Recommendations

Recording peak levels: -15 to -6 dBFS
Mixing peak levels per track: 0 dBv / -15 to -6 dBFS on each track to start, watch clipping in plugins
Mixing output peak levels: -6 dbFS to -3 dBFS
Mastering Peak Limit: -.5 dBFS
Mastering RMS: -10 dBFS or LUFS

Last Word

Remember, this is music. It’s about the quality of the sound and the groove and the emotional connection with the listener. Don’t get so caught up in watching your meters that you forget to listen to hear if it sounds good. Remember, if it sounds good, it is good!

 

 

*yes, I know about 32 bit floating point, but that is beyond the scope of this article.

Sharing is caring!
Share

New How-to Videos Up!

YouTube How toHey rockers – while you probably know I have my entire catalog of music and all of the Answer is None songs streaming on my YouTube channel, you may not know that I also have several helpful “how-to” videos up as well. One on building an inexpensive pedalboard, one on adjusting the frequency sweep on a Crybaby wah, and other guitar and gear-related videos.

I’ve added a few more recently related to recording guitar on a computer, plus some helpful basics on getting started mixing music. More will be coming, so subscribe to my YouTube channel and let me know what you think in the comment section!  Also, if there are any topics you’d like to see a video on, let me know!

Sharing is caring!
Share

How to Recover from a WordPress Hack

Wordpress LogoI’ve been an IT professional for two decades. I’ve been through just about every IT and security disaster you can imagine, except for one. A hack on a personal website — in this case the one you’re reading now. Let me tell you what I found and how I fixed it.

One recent morning, I went to create my Pick of the Week post, and instead of being able to log into my site, I was met with a note that said ANONCODERS followed by a list of the hackers’ handles. This was a surprise, because I keep everything as up to date as possible. I immediately went to work with the standard operating procedure:
1. changing my login passwords to stronger ones
2. changing the passwords of the associated email addresses
3. backing up my files and database.
After clicking the ‘forgot password’ link and resetting my admin password, I was able to get in to the WordPress dashboard and verify that all my posts and files were still there, I just couldn’t browse to them.

The next step was searching for obvious files that were changed in the last two days and removing them, and then the tedious process of looking through the rest of the files to see what I missed, and sweating every minute that it wasn’t fixed. I knew I was racing against time.

Was I worried that someone would steal financial information? No, there’s none on my site. Nothing like that. I was worried because I know that once your compromised system gets picked up by security sites, your site and domain will be blacklisted. Once your site is flagged, it affects your traffic, your search rankings, and turns away all those eyeballs you work so hard to funnel back to your little home on the web.

Cyber SecurityThe hacker message remained after I removed the files I could find, so I then installed the Wordfence plugin, which will do a scan for changed WordPress core files and look for known exploits. It did find a couple suspicious files I missed, but I still couldn’t get to any of my pages. In the meantime, I installed Bulletproof Security on my other WordPress sites and changed those passwords as well.

The next step was to reinstall WordPress in place through the update panel. WordPress updated smoothly, but even with a fresh install and all the plugins turned off, the problem persisted. At this point I had a sinking feeling that the hacker code was in the database somewhere, but I couldn’t find any unusual tables or fields looking in my host’s phpMyAdmin and comparing to another known good site.

It wasn’t until I ran a scan from the Sucuri site that I saw some information that led me to the last problem: some malicious Javascript had been placed in a sidebar widget. I simply needed to delete it in Appearance > Widgets to finish clearing the site. The whole ordeal was over in 24 hours, but the lessons remain.

An ounce of prevention really is the best cure. Honestly, it’s not that hard to use strong passwords or even two-factor authentication, and it’s not that hard to take steps to keep your site from being the ripe low-hanging fruit. But we get complacent and think it will never happen to us, I understand, believe me. Trust me when I say that a small amount of extra work up front will save you time, anguish, lost clicks, lost revenue, and loss of trust in your brand.

Recommendations: keep your site and plugins up to date with the latest patches. Use strong passwords and don’t use those passwords on other sites. Install a security plugin to help harden your site and alert you when something unusual happens. Be careful when installing third party plugins that haven’t been updated recently, or that are not well known. And maybe most importantly, make regular local backups of both your site files and your database.

Another recommendation is to not use the username “admin” as your administrator for any site. Since I installed the security plugin, I’ve been getting constant alerts about attempts from all over the world to break in by brute forcing the password for admin.

Important and helpful links!

Prevention

Hardening WordPress on the WordPress Codex has great advice
Bulletproof Security plugin
The 7 best WordPress Security Plugins according to Infosec

Cure

Help I think I’ve been hacked from the WordPress Codex helped get me off the ledge
How To Completely Clean Your Hacked WordPress Installation
How to clean a hacked site using Wordfence was helpful and doesn’t require Wordfence to follow
Cleaning up an infected website – Part I: WordPress and the Pharma Hack

*AnonCoders is a group of Palestinian web terrorists that pride themselves on defacing American and UK sites, then bragging about it on Facebook and Twitter. This is somehow vigilante justice in the name of Palestine. Good job making people sympathetic to your cause. Not.

Sharing is caring!
Share