When it comes to broadcasting, streaming, or capturing vocal tracks the Shure SM7B is one of the best dynamic microphones on the market. However, it’s common for users to experience low volumes when using this mic.
Why is my Shure SM7B so quiet?
The Shure SM7B is quiet because it has a lower output than most other microphones. This means that it requires a significant amount of gain to successfully capture audio. Without adding enough gain to the signal, the SM7B will only work at a very close distance to the sound source.
Thankfully, providing the SM7B with an adequate gain isn’t too difficult.
One of the easiest ways to do this is by using the Cloudlifter Mic Activator, or a similar device. This provides clean gain to the Shure microphone, ensuring that the recordings are audible without compromising on audio quality. In this guide, I’ll explain the reasons your SM7B is quiet in detail, and offer some solutions.
Why is the SM7B so Quiet?
To understand why the Shure SM7B is so quiet compared to most other dynamic microphones, we need to analyze some of the technical specifications of the device. The SM7B is designed mainly for capturing the human voice at close distances, hence its popularity amongst podcasters and live streamers.
It’s widely regarded as one of the best microphones you can get in its price range. Therefore, I can envisage many people being excited to test out the SM7B, only to be confused by the low volume recordings it produces when they first use it.
The reason that the Shure SM7B is so quiet is due to its output level. The output level of a microphone is essentially the default volume of the audio it captures.
Most recording engineers and audio enthusiasts would agree that ideally, the recording volume of a microphone should be somewhere between -20dB and -5dB.
This ensures that there is enough room for additional gain to be added during the mixing process, and also that the recordings are instantly audible.
The Shure SM7B’s output level is -59dB. As you can see, this is much lower than the ideal range of -20db to -5dB, meaning the audio captured using an SM7B would be significantly quieter than most other microphones.
The table below shows a comparison between the output level of the SM7B and other popular microphones.
First-time users of the SM7B may find themselves cranking the gain settings on their audio interface’s mic input to achieve a recording level that is loud enough to be heard.
- Although the microphone will function in this way, it’s not ideal to have your gain cranked as this may lead to noise issues diminishing the overall clarity of your recordings or live streams.
Cloudlifer – The Perfect Solution?
The Shure SM7B is often paired with an external device which is designed to provide the microphone with enough clean gain for it to reach an adequate volume.
One of the most popular devices in this field is the Cloudlifter. Designed by Roger Cloud, the device was born out of his frustration when using low-output dynamic or ribbon microphones.
The majority of preamps, which are designed to boost the audio signal before it enters a recording device or software, couldn’t provide the SM7B with enough gain to increase their volume to a manageable level.
Roger Cloud decided to take matters into his own hands and designed the CL-1 Cloudlifter Mic Activator. This is an active amp that provides the mic signal with a boost before it reaching the preamp. It didn’t take long for SM7B and other low-output mic users to heap praise on Cloud’s invention.
Over a decade since it first burst onto the scene, the CL-1 Cloudlifter has become synonymous with the Shure SM7B. Its success is underlined by the large number of similar products which have made their way onto the market in the years that have followed.
How the Cl-1 Cloudlifter Works
The Cloudlifter, and similarly–designed devices, work by adding gain to the signal of a microphone. It has male and female XLR ports which are connected to the SM7B at one end and the input of your audio interface/mixer at the other end.
The CL-1 applies the gain boost before the preamp stage. This is advantageous because it allows the cleanest gain boost to be added to the signal without any coloration from the preamp input being present, as is illustrated in this video.
One of the reasons this device is highly compatible with the Shure SM7B is because it has the potential to increase the gain by up to +25dB.
As I previously stated, the SM7B has an output level of -59dB, while the ideal range spans from -20dB to -5dB.
Therefore, increasing the gain of the SM7B by up to 25dB will raise its volume to a level that is much closer to that of an average dynamic microphone.
This will allow the user to turn down the gain on the input channel of their audio interface of another device, minimizing the risk of noise issues being present in their recordings and also preventing clipping from occurring.
Boosting gain isn’t too difficult, but doing it in a way that preserves the tonal characteristics and the overall quality of the audio is a challenge. The Cloudlifter can do this thanks to the inclusion of high-end JFET circuitry, which ensures transparency.
Other Ways to Make Your SM7B Louder
While the aforementioned CL-1 Cloudlifter is a highly effective tool for making an SM7B louder, certain factors such as financial budget may mean this is not a viable option for everyone.
There are many more affordable gain-boosting devices on the market, which perhaps don’t perform to the high standard of the Cloudlifter, but are worth considering if you’re looking for a less costly option.
In addition to using one of these microphone level boosters, there are some other measures you can take to prevent your SM7B from being too quiet when recording or streaming.
Firstly, ensuring that you are close enough to the mic’s capsule is essential. The SM7B is not designed to be used at long distances from the sound source and is better suited to close-up recordings.
That’s why when you see people using them on podcast videos, the speakers often have their mouths almost touching the foam pop shield of the mic.
Even when using a device like the CL-1 Cloudlifter with a Shure SM7B, you’ll still need to be close to the capsule when recording. This is especially true when recording vocals or spoken word content.
Another thing to check if your SM7B is too quiet is the angle that the mic is positioned at concerning the sound source. This ties into the polar pattern of the SM7B, which largely impacts its performance and the applications it is suitable for.
The SM7B has a cardioid polar pattern. This type of polar pattern is the most common, and it is most sensitive to sound aimed directly in from of the microphone’s capsule. The back of the microphone has almost no sensitivity to sound, while the sides have a significantly reduced sensitivity.
This means that if your Shure SM7B isn’t placed with the sound source directly in from its capsule, the volume of the recordings will inevitably be reduced. It’s therefore essential to check that the mic is the correct way around and that the sound source is facing its front side.
Another thing to consider, which granted may seem a little obvious, is the volume of the sound source. The SM7B may be a low-output microphone, but even high-output mics will struggle to capture a sound if it is already at a very low volume.
Generally speaking, the lower the volume of the sound source, such as a speaker, singer, or instrument, the more gain must be added to the signal for the sound to be clearly audible.
The SM7B can handle very high volumes due to its low output, so don’t be afraid to crank the volume on your guitar amp or speak loudly into the capsule if your recordings are too quiet.
Does the SM7B record background noise?
Thanks to its iff-axis rejection capabilities, the Shure SM7B is great at blocking out background noises when recording. This makes it a brilliant microphone for capturing vocals, whether sung or spoken.
What’s the difference between the SM7B and the SM58?
The SM7B and SM58 are two of Shure’s most popular dynamic microphones, but there are some key differences between the two. The 7B is better suited to recording in the studio and requires much more gain than the 58, which is better for live applications.
How much gain does the SM7B need overall?
The Shure SM7B requires a minimum of +60dB of gain. This can be supplied by a combination of a gain-boosing device like the Cloudlifter and the preamp, which may be integrated into the input of an audio interface.