Part I - Gain Staging & Recording Recording

As we, classical guitarists, have ventured into the world of recording, we've faced the intriguing challenge of capturing our instrument's perfect sound. After meticulously learning about different microphones, mastering the art of microphone arrays, and optimizing our room for the ideal recording tone, we often feel ready to immortalize our masterpiece. Yet, beneath this readiness lies a vast universe of elements that we need to fine-tune to achieve an optimal recording. Among these, understanding gain staging, recording levels, mixing, and mastering levels is crucial.

While there's a plethora of information available on the internet, it can often feel like trying to find our way through an intricate maze, riddled with confusing technical jargon and conflicting advice. In light of this, I've decided to consolidate my personal insights, specific tips, and favorite tools into this comprehensive guide. My aim is to shed some light on these crucial aspects and assist you in capturing and polishing your classical guitar recordings to perfection.

dB Trivia

But first, we have to familiarize ourselves with decibels or dB. These logarithmic units are used to measure the intensity of audio signals. The world of digital audio can be treacherous if you're not careful - one misstep could lead to clipping or distortion, which occurs when the audio signal exceeds 0 dBFS (decibels relative to full scale). Attention to detail is pivotal.

Recording Levels & Gain Staging: Laying the Foundation for a Great Recording

The journey to a great recording begins with understanding gain staging. Gain staging is a process that ensures a clean, distortion-free recording while leaving enough breathing room for further processing during post-production. This involves setting optimal levels of audio signals at each stage of your recording chain. In the context of home studios, this often involves just your instrument, an audio interface, and perhaps some ITB (In The Box) processing.

However, even in this simplified chain, ensuring good gain staging remains crucial. This starts with the sound of your instrument in the room. You'll need to ensure your guitar's sound is clear, resonant, and free from any unwanted noise or interference. Careful placement of the microphones is also key.

Each microphone and each placement will give a different color and character to your recording. When setting up my microphones, I experiment with different placements and distances. Finding the sweet spot is an art - it should capture the guitar's natural tone while minimizing room noise. Adjusting the distance and angle of your microphones can help control not only the tone but also the levels: too close and the sound might be overly loud or boomy; too far and the signal could be weak, leading to a noise-prone recording when amplified. Have a look at my Stereo Microphone Techniques for the Classical Guitar guide..

The next step in the chain is the audio interface. This is where the acoustic energy, the sound waves your guitar produces and your microphones capture, are converted into digital signals your computer can understand.

Your audio interface typically has preamps which amplify the microphone's signal to a level suitable for the Analog to Digital Converter (ADC). The gain knob on your interface controls this amplification. It's crucial to find the right balance here: a signal that's too weak may introduce noise when you try to increase the volume later, while a signal that's too strong risks clipping, distorting your guitar's natural sound.

Once gain staging is properly set, the next crucial part of the process is managing your recording levels. Recording levels refer to the strength or amplitude of the audio signals being recorded in your DAW. In other words, it’s about how loud the recorded audio will be.

For classical guitar, I aim for an average level (or RMS level) around -18 dBFS to -12 dBFS, with peaks not exceeding -6 dBFS. This ensures a healthy signal level without risking distortion or clipping. These values might not mean much if you're just starting out, but understanding them and using a metering tool to monitor your levels will make a big difference in the quality of your recordings.

For those of you who, like me, prefer to use an external preamp along with a separate ADC, the gain staging process involves an additional step but the principle remains the same. Using an external preamp like the AEA TRP2 or SPL Crescendo duo, allows for even more control over the tonal characteristics and the level of the signal coming from your microphones.

Once the signal is conditioned by the preamp, it then goes into a separate ADC, such as the RME ADI-2 Pro FS in my case, which converts the analog signal into digital. Adjusting the input level on the ADC is equally crucial as on the audio interface's preamp for those who use an integrated solution. The goal is the same - ensuring a healthy signal level without risking distortion or clipping, which for me is around -18 dBFS to -12 dBFS RMS, with peaks not exceeding -6 dBFS.

This might seem like an extra layer of complexity, but in my experience, the flexibility and control provided by separate high-quality preamps and ADCs can lead to even better results, and it's worth considering if you're serious about recording.

To sum up, good gain staging for a classical guitar recording involves capturing a clean signal from your guitar, through the air, into your microphones, then into your audio interface, and finally into your DAW. Each step requires careful attention, but with practice and patience, the results can be immensely rewarding.

Additional Tips for Optimal Gain Staging:

I mainly use Vovox Sonorous and Sommer Epilogue cables for a peace of mind

Starting with a Clean Signal: The quest for the perfect recording begins long before hitting the record button. I ensure that my guitar is properly set up and my strings are in good condition to minimize extraneous noise and to allow for effecient dynamics.
High-Quality Cables: Cables can often be overlooked, but they are a critical part of the signal chain. Investing in high-quality cables can prevent unwanted noise and interference in the signal.
Room Acoustics: The room's acoustics can impact the recording significantly. A quiet and sonically balanced room can help ensure a clean, high-quality recording.
Monitoring the Signal Chain: Vigilance is key throughout the recording process. By continuously monitoring the levels throughout my recording chain, I can prevent unexpected overloads or distortions and ensure the best quality recording.

Using Metering Tools for Precision

Youlean Loudness Meter is an essential tool

For those of us who want to be precise with our levels, I highly recommend using metering tools. One of my favorite tools is the Youlean Loudness Meter. This handy software allows me to monitor not only the loudness of my recording but also the dynamic range. The free version is good enough for most cases, and you can support the developers by purchasing the pro version which provides some additional features.

Maintaining Dynamic Control

Classical guitar's essence lies in its subtleties and nuances. Dynamics - the interplay between the quietest and loudest notes, crescendos, decrescendos - bring the music to life, allowing your listeners to connect more deeply.

When setting my recording levels, I always leave ample headroom for these dynamics, striking a balance so that the louder sections don't cause distortion or clipping and the quieter parts remain clear and noise-free. Remember, amplifying a quiet, clean recording is always preferable to fixing a loud, distorted one.

Additionally, transient details - quick, high-energy moments - require careful attention to avoid distortion or getting lost in the mix. Proper recording levels ensure these moments are accurately captured, adding to the richness of the final recording.

Striking the Right Tone

In conclusion, understanding and managing recording levels, along with proper gain staging, can make a significant difference in capturing a perfect performance. It can be the difference between a recording that sounds amateur and one that stands up to professional scrutiny. With careful attention to detail, patience, and practice, you'll be on your way to making recordings that you can be proud of.

Stay tuned for Part II of this series, where we'll dive deeper into the realm of audio recording as we explore the importance of levels in the post-production stages - mixing and mastering. This is where your carefully recorded tracks are polished into a cohesive, balanced, and compelling final product. Until then, happy recording!