Polarity & Phase
Phase is defined as a time relationship between two waveforms. This can cause frequency builds and cancellations, which will smear the integrity of your recording. Here is a hard and fast rule:
Any time we have more than one mic on the same source (e.g. top and bottom snare), we must flip the polarity of one mic to check the phase relationship.
Polarity is the process, phase is the product. We flip polarity to create a different phase relationship.
Ø is the polarity symbol. It is usually located on the mic pre, but can also live in an interface’s companion software. Flipping the polarity on one of the mics allows us to check the sum frequency response of the two mics and verify that there are no phase issues detracting from the sonic texture of the recording. Make sure to use whichever polarity position produces a thick, rich sound. The A/B process will be very obvious as to which position creates the best phase relationship.
The electrical current generated by a microphone is very small (measured in millivolts). In order to use any microphone, it has to pass through a preamp (or “pre” for short) in order to become a “line level” signal. There is no exception, as every mic needs to pass through a mic pre in order for it to be used or recorded. Here is the catch: the quality of the mic pre plays an arguably bigger role than the actual microphone.
Generally speaking, the quality of a mic pre moves up and down with price. The pre on a starter-level interface ($200 - $400) will sound greatly inferior to a BAE 1073 ($3,135). Pairing a well-selected mic with a professional-level mic pre can yield results that far surpass what can be achieved with inferior gear.
I had personal plans for the evening on March 8th, 2012. Around 6pm I received a phone call from Steve Burdick. Steve is the owner/operator at Westlake Recording Studios and the phone call went something like this:
Me: “Hey Steve.”
Steve: “Doug, I have 3000 coming in to Studio C at 8pm and I need a veteran.”
Me: “Done. I’m on my way.”
That was all I needed to hear in order to break my plans: a session with Andre 3000. I got dressed, hopped in the car, grabbed a Red Bull on my way and arrived 45 minutes prior to downbeat. After entering the studio I asked the 2nd engineer, Matt Brownlee, to set up a vocal chain of a Sony C800G/Neve 1073/Summit TLA-100. I chose this chain because:
- C800 gives me a bright, detailed tone
- The 1073 provides rich, crisp harmonics and gain
- The TLA-100 has a nice, thick tube sound and really warms up the voice
Andre arrived solo and we exchanged pleasantries. He told me that the session was actually a feature for a songwriter named Frank Ocean and that Frank was to arrive soon, so Andre and I talked shop for a bit while we waited. During this time, Andre handed me a hard drive and said, “Can you open the session called Pink Matter?” I pulled up the session, imported my vocal template and we took a brief listen. When playback arrived at his verse he said, “Okay, I already cut some vocals and I want to use the same mic.” When I asked which microphone he used, he responded “an SM57.” As my mind silently spoke words that are not appropriate for this column, I verbalized “sure, no problem at all.” I instructed Matt to replace the gorgeous C800 with the 57 in the existing vocal chain.
Frank arrived solo a short time later (I have been fortunate enough to have sat in many studio power triangles over the years). Everyone assumed their position, with Frank behind the console, me behind the computer and Andre in the booth. I dialed in the vocal chain and heard a surprising result: the vocal crossed the professional threshold and didn’t sound bad! We started recording, but like any session, it was not without a speed bump or two. I’m known for being nimble behind the Pro Tools rig, but we were having some buffer and latency issues, probably due to a preference from the previous session. I was able to manage the issues and finish cutting the vocal, albeit a bit slower than normal. The session wrapped successfully, including a full preview of Channel ORANGE, and we all went on our respective ways.
With regard to the purpose of this writing, what can we take away from this story from a microphones perspective? First thing is first: purchasing an SM57 and wiring it to a $500 interface will not fetch a GRAMMY nomination. Bear in mind that this 57 was put through a fantastic mic pre and compressor, so its sonic characteristics were greatly enhanced. Having an incredible artist on the other side of the 57 certainly goes a long way as well.
What is safe to say is that while the microphone is a very important part of the input chain, the other components (pre and compressor) matter greatly. A microphone that isn’t necessarily designed for vocal recording can be enhanced enough by a high-level vocal chain to be useable on a voice.
All of the considerations we have discussed can make purchasing a microphone for your studio a daunting task. Try breaking down the process into simple steps. Determine what you will be recording (vocals, etc.) and how much money is in the budget. Then begin researching options that meet the objective and fit the budget. Remember to ask the retailer if it is possible to demo a mic before purchase. Some manufacturers allow people to demo, some do not. It never hurts to ask. Demoing a mic before committing to purchase will provide the best insight and help significantly during the decision-making process.