Technical Audio Specifications for Voiceover

Voice actors typically deliver files in WAV or MP3 formats, but you can request any audio format needed for your project. Simply specify your preferred format when requesting a quote or before the recording.

• MP3 files are compressed audio files, ideal for web and e-learning, while WAV/AIF are lossless formats with no quality degradation, and larger file sizes.
• For video content, we recommend using audio files in WAV format (24-bit/48 kHz), while e-learning platforms typically use MP3 files for faster loading.
• Always archive master recordings in WAV format for future editing or repurposing.

• Multiple format versions are available upon request at no extra charge.

Raw audio is the unprocessed recording straight from the voice actor’s microphone with no editing or processing. Voice actors’ typically just remove major mistakes and long pauses, but leave breaths and background noise unprocessed. Mastered audio has been professionally processed with noise reduction, EQ, compression, De-Essing, and fine-tuned editing to deliver polished, broadcast-ready files. Most projects require mastered audio, while raw audio works for clients with their own post-production team or specific editing requirements.

• Both raw and mastered audio begin with broadcast-quality recordings. Mastering adds that professional polish, making the file ready for final production.
• Mastered audio should meet broadcast loudness specifications (typically -24 LUFS for TV/online broadcast, and -16 to -19 LUFS for streaming/podcast content.
• Voice Crafters offer post-production services beyond standard mastering, like our curated music catalog, multitrack mixing, captioning, and more.
• We recommend requesting both audio file options: raw files for archival/backup purposes and mastered files for immediate use.

The industry standard for broadcast audio, voiceover included, requires uncompressed digital audio formats, such as WAV or AIF, at 24-bit, 48 kHz. In terms of loudness levels, standards can vary depending on location. In the US, the FCC (Federal Communications Commission) enacted the CALM Act, which defines the average audio loudness of TV commercials. Voice Crafters broadcast audio deliverables meet technical specifications and loudness standards, respecting the broadcast location.

• International standard (EBU R128) mandates a loudness level of -23 LUFS (Loudness Units relative to Full Scale) for European and many international broadcasters. In the US, the CALM act requires -24 LKFS (Loudness, K-weighted, relative to Full Scale) for TV commercials.
• LUFS and LKFS are functionally identical measurements, just have different naming conventions for the same loudness standard.
• Voice overs are usually delivered in mono. Stereo is required when the VO is mixed with a soundtrack and/or sound effects.
• Streaming platforms like Netflix (-27 LUFS), YouTube (-14 LUFS), and Spotify (-14 LUFS) have different standards than traditional broadcast.
• Peaks are typically limited to -3dBFS (decibels relative to Full Scale) to prevent digital clipping and allow encoding headroom.
• Professional compression and limiting are usually applied to meet broadcast specs while preserving vocal intelligibility.

The noise floor measures the background noise level in an audio recording environment. It is the ambient sound that is present during “silent” moments when the voice actor isn’t speaking. Professional broadcast voice overs require a noise floor of -60dB or lower to ensure clean audio without audible hiss, hum, or room noise. Higher noise floors distract listeners, degrade the perceived audio quality, and can cause audio issues when processing.

• Noise floors are caused by insufficient soundproofing, HVAC systems, computer fans, electrical hum, microphone self-noise, an analog preamp’s noise, etc.
• A loud noise floor sounds unprofessional, distracts from the message, and signals low production quality.
• Modern noise filters can mitigate noise to a certain degree. When overused, they can introduce artifacts that degrade the overall audio quality, so proper soundproofing and acoustic treatment are paramount.
• Voice Crafters’ talent must demonstrate a low noise floor during the vetting process to be accepted to our roster.
• Noise floor that seems hidden during speech becomes obvious during pauses, edit cuts, and sentence endings.

Yes, you can certainly request custom file splitting and naming conventions to match your workflow requirements. Make sure you specify your specific needs clearly in your creative brief before the voice actor begins recording, and ask them about what they charge for this task. You may want to split the audio by paragraph, slide number, chapter, or scene, with naming that reflects your organizational system. Most voice actors will typically include these requests in the project’s proposal, though a complex project with dozens or hundreds of files may involve additional fees depending on the scope.

• E-learning courses often need audio files split per slide, with numbering that matches the LMS (learning management system) structure.
• Video sync projects may need the audio by scene or timecode for an easier editing workflow. This is especially helpful when a video editor works on syncing a voice over in a foreign language they don’t speak.
• Audiobooks, GPS, Audioguides, and IVR systems also typically need audio files split, and sometimes include specific audio formats and encoding for their system.
• Voice Crafters agency can manage complex file organization requirements as part of our project management services.

Audio professionals use DAWs (Digital Audio Workstations) like Adobe Audition, Pro Tools, Logic Pro, or Reaper (among others) as the platform on which they record, edit, and process audio recordings. Within these DAWs, tools like equalizers (EQ) to balance frequency response, compressors to control dynamics, de-essers to tame harsh sibilance, limiters to prevent clipping, and noise reduction tools to eliminate unwanted background sounds. These tools work together to process raw voice recordings into broadcast-quality professional audio.

• EQs, like FabFilter Pro-Q, Mäag EQ4, and stock DAW plugins, help remove muddiness, enhance clarity, reduce resonances, and balance tonal quality.
• Compressors, like Universal Audio 1176, Waves CLA-2A and stock plugins, control dynamic range and even out volume levels to maintain consistent loudness throughout the recording.
• Metering tools, like iZotope Insight, ADPTR AUDIO Metric AB, and others, check Loudness levels and ensure compliance with broadcast standards.
• Noise gate plugins, like iZotope Rx, Waves Clarity, Accentize dXRevive, and others, remove background hiss, hum, air conditioning, computer noise, and environmental interference.