Home Recording Studio Upgrade
In 2011, after years of using basic Logitech headsets that never lasted more than a few months, I began my journey down the rabbit hole of audio with the purchase of a Blue Yeti USB condenser microphone.
Its construction is impressive and the improvement to my sound quality was marked. For certain use cases, in the right recording environment and with the right settings dialled in (a matter of some trial and error), the Yeti is very competitive at its price point. Its wide frequency response of 20–20,000Hz (well beyond most adults’ hearing range), selectable polar patterns and built-in headphone amplifier for live monitoring make it suitable for podcasters, musicians and vocalists alike. I rate it highly; it’s worth considering if you’re on a budget and looking to step up your audio game (though proprietary accessories, like the Blue Radius II shockmount, are exorbitantly priced). Other candidates include the Audio-Technica AT2020USB, the Rode NT-USB and the Samson Meteor.
For livestreaming and podcasting in a small, untreated bedroom studio like mine, however, the Yeti has its limitations. In looking to upgrade, I initially considered more high-end condenser microphones like the Audio Technica AT2020 and the Rode NT1 (used by such prominent YouTubers as PewDiePie and Barnacules). After more thorough research, however, I realised that a dynamic microphone, favoured for decades by radio broadcasters, was a much better solution.
Condenser versus dynamic microphones
The physics behind condenser and dynamic microphones is the same: both are transducers, converting the kinetic energy of sound waves into electrical signals (this process is reversed by loudspeakers). Their mechanical differences and nuances are beyond the intended scope of this article but, generally, condensers are more sensitive and have wider frequency responses. A more sensitive microphone, however, picks up ambient noise as well as whatever you’re trying to record: it can’t discriminate. In an environment that has not been acoustically treated or with poor microphone placement, a low signal-to-noise ratio results.
Dynamic microphones are typically less sensitive and less prone to distortion when the source is very close. Thus, when the proper microphone technique is used, i.e., when the source is close to the microphone, the signal-to-noise ratio is higher. In other words, dynamics tend to reject noise better than condensers. When computer fans, mechanical keyboards and noisy roommates are a factor, the advantages of dynamics become clear.
Ultimately, after considering offerings from Electro-Voice, Shure and Rode, I settled on the Shure SM7B. While not cheap, it compares favourably to microphones many times its price. It is a staple in recording studios and was famously used by Michael Jackson on Thriller. It has a cardioid pickup pattern, an internal shockmount, comes with two different foam windscreens (to reduce distortions from plosives) and is well-shielded from electromagnetic interference, which is of particular concern in a home office with monitors and other gear.
Image: © Shure
Audio interfaces and mixing consoles
One downside to studio microphones (which use XLR connectors) when compared to USB microphones is that they need to be connected to a computer via a separate audio interface. I considered popular USB audio interfaces from Focusrite, M-Audio and Steinberg, to name a few. However, these all rely on a digital audio workstation (specialist software) if you want to apply, e.g., equalisation or effects.
A USB mixing console, on the other hand, offers hardware controls and uses either digital, onboard processing or physical, analogue circuitry to modify input signals before feeding the mix into the PC. This has the added benefit of lightening the CPU load (a valid concern when you’re using a single PC to play and stream games simultaneously) and reducing input latency.
I read dozens of reviews of mixers from Allen & Heath, Behringer, Soundcraft, Yamaha and others before settling on the Yamaha MG12XU. This model, while lacking parametric equalisation, ticked every other box: metal construction; a small footprint; excellent microphone preamps; volume faders, effects and muting for each channel and, crucially, one-knob compression.
Image: © Yamaha
Compressing an audio signal means reducing its dynamic range by amplifying quiet sounds and/or attenuating loud ones. This is useful in live applications where a speaker’s volume and position relative to the microphone can vary.
While it doesn’t compare to a standalone compressor, the MG12XU achieves great results in my particular use case and takes up much less space.
Preamplification
Given the popularity of condenser mics, which are particularly sensitive, most modern mic preamps only give about 40–50dB of gain (volume). While the MG12XU’s preamps offer 64dB of gain, the Shure SM7B’s output level is notoriously low, even among dynamics, at -59dBV/Pa. In other words, when paired with the MG12XU, the SM7B’s output signal is quiet even when maxing the gain, something that also tends to introduce noise into the signal.
One solution (recommended by Shure themselves) is a device like the Cloudlifter CL-1 mic activator. It takes phantom power from the mixer (usually required to drive condenser mics) and gives an inline signal boost of roughly 25dB. I’ve found that it works a treat, leaving plenty of headroom and introducing no perceptible noise.
Teething problems
While I’d love to tell you that was the end of the story, I would be in for several weeks of troubleshooting before everything Just Worked™. I was experiencing sporadic audio dropouts: sometimes once or twice a day, sometimes every few minutes. The problem persisted with different mics in different input channels and when removing the Cloudlifter CL-1 from the chain.
The only solution was to power the mixer off and on and restart whatever applications I was working in: not ideal. I tried every version of the Yamaha Steinberg USB drivers compatible with Windows 10 (I found references online to similar issues with other Steinberg audio interfaces). I tried different USB cables and ports. I tried unplugging every USB device save for my mouse and keyboard. I tried a PCIe USB expansion card to rule out any issues with the USB ports on the motherboard. I tried pricey, shielded XLR cables and different power outlets and surge protectors to rule out an electrical issue. A replacement mixing console didn’t fix the problem and Yamaha’s technical support team were flummoxed.
I had decided to return the unit and try a model from Soundcraft when I found a thread buried in Line 6’s forums by a user having similar difficulties with one of their audio interfaces. A poster suggested disabling any entries for “AMD/Nvidia High Definition Audio Device” or similar in Device Manager. I don’t use my GPU’s ports for audio so I figured it was worth a shot; I uninstalled Nvidia’s HD audio drivers for good measure. After several days (now weeks) without any audio dropouts, I was confident enough to call the problem solved. Interestingly, Yamaha is Line 6’s parent company so it’s likely their audio interfaces use the same or similar drivers as the MG12XU. Whether the presumed driver conflict is the fault of Nvidia/AMD, Yamaha/Steinberg or Microsoft, I am not sure, but perhaps this article will be of help to someone experiencing similar issues.
Conclusion
Now that headache’s over, I’m enjoying the new setup. The SM7B, in concert with the mixer’s D-PRE mic preamps, delivers rich, clear sound and background noise is greatly reduced. The mixer’s hardware mute is a lifesaver when I’m live but need to step away from my desk at short notice—cats, cups of tea and phone calls happen. While a headset or USB mic is undoubtedly much less expensive and maybe more convenient, the improved production value of my streams is something I’m really proud of.
