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Parallel Compression
Just because you failed high school trigonometry doesn’t mean you can’t use and profit from parallel compression in your mixes. Parallel or “upwards” compression is simply the process of combining an un-compressed signal with a compressed-one and blending to taste. This ‘best of both worlds’ approach is designed to preserve the dynamics, openness, punch, character and frequency response of the un-processed signal while solving the issue of the overly dynamic track getting lost in the mix or sound thin/weak.
The Setup:
While many newer dynamics plug-ins feature a built in “wet/dry” mix parameter that allows inline parallel compression tricks, you can easily achieve this effect with any compressor/limiter. Basically we are going to duplicate the track we want to compress, add a lot of compression to the duplicate and blend with the original to taste. Essentially what this is doing is creating a dense ‘bed’ of sorts for the uncompressed track to ride on, preserving all the original dynamics while allowing the track to sit comfortably in the mix. This trick can be used in subtle or extreme ways and works well on almost any source material, especially where transparent and natural sounding dynamics control is desired.
Parallel Compression Tips:
Drum Squash: Create a aux return with an aggressive compressor or limiter on its insert, you can call this “Squash Bus.” Using sends, send all your drum tracks accept the kick drum to this squash track and blend with the original (dry) drums to taste. Leaving the kick drum out prevents the squash track from over-reacting to the dynamics of the kick, which tends to dominate the other drums. You can experiment with including the kick to create cool pumping effects on the squash track. Try EQing this squash track in different ways, or even add distortion for an over-the-top effect.
Automation: Automate your parallel track up and down at different sections of the song, bring it in during the choruses for more power and support, bring it down during the verses for a more intimate feel.
Using a Limiter: For natural dynamics control on vocals, guitars, etc. try using a very fast (brickwall style) limiter on the uncompressed track just to keep the peaks under control so nothing jumps out of the speakers (you know, in that uncontrolled, “karaoke” sounding way). Then use the parallel track to subtly bring up the valleys and fill in the body/sustain of the track. This works really well on vocals with a ton of plosives (e.g. hard P or T sounds) that you don’t want to over compress. The brick wall limiter will transparently grab and control those plosives transients while the parallel track will bring up and support any softer sections without having to squash the crap out of the vocal.
Compensate for any delay to maintain phase coherency: Because some compressors/limiters incur a small amount of processing delay (usually do to look-ahead algorithms) it is important that each component of the parallel chain is delayed by the same amount. For instance, if you were to create a duplicate track of a vocal and apply a L1 Maximizer to the duplicate (parallel) track, there would be a noticeable latency and serious comb filtering would be heard when both tracks are played together. Most DAWs (except for Pro Tools) handle this automatically as part of their built in PDC (plug-in delay compensation) engine. In Pro Tools LE/Mpowered, the easiest way to solve this is to copy the plug-in to the original “dry” track and bypass it, thereby incurring the same delay on each track. A more permanent solution would be to shift the duplicate track backwards by the amount of delay the plug-in is causing. In Pro Tools HD you should always use delay compensation when mixing/editing. Remember, not all plug-ins incur a delay, in fact many do not, so considering using those when creating parallel chains.
This entry was written by , posted on October 28, 2009 at 12:10 pm, filed under Articles, MixTips and tagged compression, mixing, MixTips, pro tools. Leave a comment or view the discussion at the permalink and follow any comments with the RSS feed for this post.
So I use quite a few “wrapped” RTAS plug-ins, meaning that the plug-in was designed for VST and hacked (via FXpansion’s VST-RTAS wrapper utility) to work as RTAS in Pro Tools. For example, all of the UAD stuff shows up as wrapped plug-ins in my inserts menu. This isn’t a big deal, as with most VST plug-ins the wrapper utility works flawlessly, but no matter which plug-in you end up using, it hides itself in the “Wrapped Plug-ins” sub-menu of your inserts menu. I have talked to Avid (Digidesign) about this and unfortunately, as long as they are “wrapped” VST plug-ins there is no way to get them into their correct categories (e.g. EQ, Dynamics, etc), aside from possibly hacking the plug-in .dpm file (I’ve looked into this. Without some sort of hint as to how the category identifier is determined/stored, I can’t see anything obvious when I pull up the files in a hex editor). While there is currently no easy way to get the wrapped plug-ins into their correct catagories, there is an easy workaround of sorts that will get you to your favorite plug-ins quickly.
Default EQ and Dynamics:
The first thing you want to do is set up your mixer’s default EQ and Dynamics plug-ins, these will show up at the highest level of the insert selection menu so put your “go to” EQ and compressor plug-ins in these two slots. To set the default EQ/Dynamics choose Setup > Preferences > Mixing Tab.
Plug-in Favorites:
The default EQ and Dynamics option only allows you to save one favorite within the EQ and Dynamics sub-menu, which blows if you want use a wrapped plug-in as your favorite EQ or compressor. In this case, you can save a plug-in as a “favorite” and it will show up at the top of the plug-ins list (within the plug-in type sub-menu on stereo tracks, e.g. TDM/RTAS or multi-channel/multi-mono).
To save a plug-in as a favorite: Hold Command (Mac) or Control (Windows) while selecting a plug-in from the inserts menu. The plug-in will not be inserted but will be stored as a favorite. Remember, you must hold Command (Mac) or Control (Windows) before clicking on the track’s insert selector.
To remove a plug-in favorite: Repeat the steps above, hold Command (Mac) or Control (Windows) and re-select the plug-in stored as a favorite from the insert selector menu.
You can have as many favorites as you’d like however keeping this list small will ultimately save you more time.
This entry was written by , posted on October 19, 2009 at 12:12 pm, filed under Articles, MixTips and tagged mixing, MixTips, plug-ins, pro tools. Leave a comment or view the discussion at the permalink and follow any comments with the RSS feed for this post.
MixTips is a little column I worked up for my blog. The content represents tips, tricks and insights that have worked well for me over the years. I believe mixing is an art form, not a hard science. There are a million and one ways to achieve a specific result, so feel completely free to disagree with me at any time 
MixTips – Equalization
EQ is an extremely powerful tool for shaping the frequency balance of elements in a mix, it can bring things forward or push them back, allowing you to create or take away focus, and hi-light important elements while keeping others from being distracting. EQ can help repair poor recordings and make samples and loops play nice with each other in the mix. Here are some tips that I have learned over years while mixing with EQ:
Avoid making EQ decisions in isolation. While it is tempting to solo the track you are working on, this takes away the context of the track within the mix. It is very common for a track to sound dull or even bad in isolation, but work well in context. Hint: Instead of soloing, turn the track up to help during the EQ process.
Use EQ to create perspective in your mix. Since mixing is largely about directing the listener to a focal point, it is not weird to think that one might purposefully make an element sound dull to make another stand out. Example: Think about a photographer purposefully making objects out of focus to highlight the subject.
Sometimes the mute button is the most effective EQ. If something isn’t working out, as in you just cant seem to EQ it into the mix, sometimes it is best to re-evaluate the arrangement and ask yourself if it really belongs in the mix. Remember not all elements have to be playing all the time; an interesting arrangement/mix evolves and changes over time.
Cutting is generally preferred over boosting as it doesn’t eat up head room in your mix and will exhibit less ‘color’ from the filter. In other words, it is easier to hear the EQs flavor when boosting.
Be mindful of tracks with lots of low end. Remember that low frequencies are physically much longer than high frequencies and take more time to develop, ultimately taking up more space in a mix, so it is common to aggressively cut the low end of tracks that aren’t vital to the ‘bass’ component of the mix using shelves and hi-pass filters.
By design Instruments tend to have too much, rather than too little.
Create complimentary EQ curves for your low-end elements like Kick and Bass, avoid eating up to much low end head room by boosting at separate frequencies on these elements.
Most amateur mixes I hear have serious problems in the low end, because of bad room acoustics or too many low end elements fighting each other and creating mud.
Make sure you work within an instruments frequency range.
If an element doesn’t have anything to boost in the low or high end, EQ cannot create material that isn’t there.
Use a spectrum analyzer to help visualize a signals frequency make-up, but remember these are not a replacement for your ears.
Listen! – You can read a list of frequencies from a book (e.g. Thump on kick is at X Hz, snap on snare is at Y Hz) but until you bring up the track and sweep an EQ you wont know where those traits really live in your specific track.
Use EQ presets sparingly. Every instrument and voice is different and the recording process can dramatically change the frequency characteristics of a track. Even the key of the song factors into the EQ process. There is no way for a preset designer to know how you recorded your track or what context you want to use it in.
Remember that frequencies directly relate to pitches and octaves in the musical world. Think about where the fundamental and the harmonics of the instrument live. For example, the lowest note sung in a vocal can provide important clues as to where to filter the low-end.
Spectral Mixing – relating frequency to pitch while EQings
Don’t boost your kick drum sharply at a frequency that is dissonant to your song.
Different styles and tempos of music will have different approaches to EQ. For example, a fast heavy metal tune will likely have a very bass light, “beater heavy” kick drum due to the speed of the kick pattern and tempo of track, where as a hip hop tune at 90 BPM may have much more breathing room for a super low kick sound.
Faster songs tend to have less room for low end and must be mixed ‘tighter’
Break your mix up into frequency zones – e.g. low, low-mid, mid, hi-mid, and hi. Manage these zones like departments of a business, e.g. who works in what department and what do they do? What elements play a role in multiple zones? Make sure your business is efficient. Are three people doing the same job? Do you really need three people doing that job or is it just making things more confusing. Remember that mixing is part of the bigger “arrangement” picture and selecting elements that work together in the first place prevents the need for heavy EQing at mixdown.
Remember, there is no “recipe” for EQ, as everything is dependent on the arrangement and intruments within. If someone asked a chef “how can I prepare a potato to eat,” I bet he/she would ask you back “Well, what do you want to do with it? What do you like? What other foods will be served along side this potato?” There are dozens of ways to prepare potatos depending on the context, and there are even more ways to EQ a track within a mix.
This entry was written by , posted on October 13, 2009 at 2:47 pm, filed under Articles, MixTips and tagged mixing, MixTips, pro tools. Leave a comment or view the discussion at the permalink and follow any comments with the RSS feed for this post.
