Mixing in Pro Tools with Analog Hardware is one of the many techniques used by professional engineers. For many years certain devices in the studio have become “infamous” amongst engineers and producers. The never-ending list includes equipment such as a FairChild Compressor, Tube-Tech EQ, Amek 9098i Channel Strip, Lexicon FX Processors, along with dozens of other unique and flavorful devices that are still used to this very day. While the majority of these “classic” devices gained their notoriety during the hey-day of analog recording, they are also being utilized this very day in the latest Pro Tools based digital studios. The power of Pro Tools lies not only with what it can do, but also with its ability to incorporate hardware and software together into a seamlessly package.
The usage of equipment in this way goes back to analog consoles, which allowed user to plug in various equipment by “patching in” (connecting) the input and outputs to the console. The only difference we have nowadays is that our “console” is called Pro Tools and the “patching in” occurs via the Audio Interface. If we follow the same rules of signal flow our forebears did, we can patch in any piece of hardware equipment directly into Pro Tools, just as if it were an analog console and tape machine.
The main component of a Pro Tools system that will allow you to plug in your hardware is an Audio Interface. These come in all shapes and sizes, MBox, Apogee Duet, Focusrite, Avid HDX I/O, etc... You’re probably using yours to plug in your microphones or instruments as well as to connect your speakers and headphones. This same interface can also be used for connecting other hardware devices in and out of your system. The main thing to be aware of is how many inputs & outputs your audio interface has. If you are using one with only 2 inputs / outputs, you’re not going to be able to utilize very much hardware because the existing 2 outputs are probably used to feed your speakers/headphones. You will need an interface that has more than 2 in’s / out’s in order to allow hooking up the speakers as well as other devices simultaneously. I would recommend an audio interface that has at least 4 analog input / outputs. This will allow you to hook up a pair of speakers to output 1 - 2, as well as utilize input / output pair 3 - 4 to connect hardware. You could connect two separate mono devices or a single stereo device. To keep it simple, you need analog input / output points in order to plug in analog equipment. Hooray Signal Flow! Almost forgot, you’re also going to need cables to connect everything.
All of us have launched a plug-in in Pro Tools and fiddled around, but have you ever thought about what is actually going on with the audio signal. Pro Tools is a direct descendant of analog tape-machines and consoles, especially when it relates to how the audio signal is flowing around the environment.
Quick crash-course: press Play, audio signal flows Out of the Tape Machine (hard drive), In on a console channel, Out/In on Insert Points in each channel, Output path is selected for each channel (bus, aux, main), audio flows Out of the console main outputs In to the speakers. Ta-Da! The most fundamental concept of Signal Flow.
Pro Tools works exactly the same way, the hard drive is the tape machine, audio signal is played out on individual tracks, each track has Output and Send assignments, as well as Insert Points. What most people call “plug-ins” are actually known as Insert Points, there are 10 of them, each can accommodate a Software Insert (plug-in) or Hardware Insert. In the picture above, notice the “i/o” label at the bottom of the Insert List is showing all the available audio interface Input/Output points, with the one’s showing in “yellow” as already in use within the session. In my example, Output 1-2 are used for the speakers, leaving me with 14 available Input/Output points to plug in analog hardware.
In my example, I have choose i/o point 5 to plug in a hardware compressor. I have attached an audio cable from Output 5 on my audio interface to the Input of my compressor as well as a cable from the Output of the compressor to Input 5 on the Audio Interface.
**It is very important to note that when using Hardware Inserts in this manner you must use the same numbered input and output points. Just as with a console, the insert input & output points on the same channel, preserving the flow part of “signal flow”. Every input needs to feed an output, which in turn feeds an input, until audio signal is finally output from speakers and input into our ears.
Personally, I like using analog hardware on certain elements of a song to give them more life and character. Almost every person in the music industry I work with has the same plug-in’s, even I have all of the standards that need to be present in professional sessions: Waves, McDSP, UAD Cards, etc... Plug-in’s allow creative people to exchange sessions and build an entire production without ever having to leave their homes. From the stand point of a mix engineer, equipment such as compressors, fx processors, and all that other funky stuff you see in the Sweetwater catalog, are what is needed to make their part stand out.
This bring up a very good question: If the mix engineer is the only one who has this equipment, how will everyone else hear it? My answer to you is so shocking and amazing you might want to hold on to your seats: We record it!
The only way to ensure that everyone hears exactly what you want them to hear is to record it. Since we already have audio signal routed to, and from the audio interface, it’s quite easy to create a new Audio Track and record the audio signal. Assign the Input of the Audio Track to the same Input you plugged your analog hardware into. In my example it was Input 5. In the picture above, I’ve created a new Audio Track, assigned it’s Input to 5, I’ve muted the original track that is feeding the hardware compressor, click Record and away we go. You can press Mute on the original track because the Mute function happens after the Insert stage of the track. The audio signal is flowing out of the system, fed through analog hardware, flowing back into the system while it is being picked up by the new track and recorded. Hooray Science! In my example, the audio signal is flowing through a software plug-in eq by McDSP, out to a RETRO Doublewide Compressor, recorded onto the new Audio Track. From this point on I will be using this vocal track as the starting point of vocals in the mix, guaranteeing that when I pass this mix back to the artist they will hear exactly what I’m hearing.
As an extreme example of using Hardware Inserts, you could route each track through an analog console and do all of your mixing in the analog realm. It does require the presence of said console as well as the knowledge of how to use the console. Utilizing the I/O capabilities of Pro Tools along with a console can yield some very interesting sonic results. For example, you could use the Hardware I/O as the very first Insert on each track to route to/from the console and still have another 9 Insert points remaining to utilize plug-ins. Most people that use this method tend to bring up the console faders to 0db and leave it there, choosing to use the console for tonal “flavor” more than mixing. The console in that case is acting as Hardware Insert not a mixing desk, the body of the mix is still done in Pro Tools.
With the wide variety of analog hardware available it’s easy to see how music makers are able to keep getting such a wide variety of sound and texture. Try to incorporate some of the hardware you might have into your mix, you might be surprised at the results. Another great option is to book studio time. It’s no secret that the studio world is not what it used to be, many have become a lot more affordable to book. In most markets you can book a studio for a few hundred dollars a day, and you have access to the whole collection of equipment they possess. Not a bad bargain for all those buttons and knobs.
If you enjoyed this article, consider joining us in one of our hands-on Pro Tools Training Classes at one of our locations nationwide. Whether you want to spend just a few days or a few weeks to obtain official Avid Certification, we can help you take your creativity to the next level.