Blog
Loudness, recording and delivery, explained
Practical guides to podcast and audiobook loudness standards, recording quality and file formats, based on the published specifications.
ACX Audio Requirements Explained, Rule by Rule
A plain-English walk through every current ACX submission rule, from the -23 to -18 dB RMS window to room tone and credits, with how to meet each one and a checklist.
BroadcastEBU R 128 vs ATSC A/85: Broadcast Loudness Compared
Europe targets -23 LUFS on the whole programme; US television targets -24 LKFS, measured on dialogue for long-form. Targets, tolerances, true peak, LRA and short-form rules side by side.
AudiobooksHow to Get an Audiobook Noise Floor Below -60 dB
How the ACX noise floor is measured, why levelling raises it, and how to get below -60 dB with recording fixes and gentle processing instead of gating pauses to silence.
RecordingHow to Reduce Background Noise in Voice Recordings
Noise is easier to prevent than to remove. Start with the room, the microphone distance and the gadgets around you, then use processing for what is left.
LoudnessLoudness Normalization Explained: Spotify, YouTube, Apple
Players turn loud files down and quiet files up at playback. What Spotify, YouTube and Apple actually document, which numbers are only observed, and why louder masters do not win.
LoudnessLUFS vs RMS vs Peak: What Each Measurement Means
Peak, RMS and LUFS are all in decibels but measure different things. What each one tells you, how loudness meters weight and gate audio, and why specs choose the one they do.
PodcastingMono vs Stereo Podcasts: Which Should You Publish?
Mono halves the data a voice-only show needs but changes how loudness is measured. When to choose it, what -19 LUFS is for, and what Apple, Spotify and ACX expect.
FormatsPodcast and Audiobook File Formats: MP3, AAC, WAV, FLAC
Which formats, bit rates and sample rates Apple, Spotify, YouTube and ACX document, how CBR and joint stereo trip up audiobook uploads, and what to keep as your master.
LoudnessTrue Peak vs Sample Peak: Why Inter-Sample Peaks Matter
The highest sample is not the highest point of the waveform. How inter-sample peaks arise, why encoders make them worse, and why delivery specs set true-peak ceilings.
PodcastingWhat Loudness Should a Podcast Be? LUFS by Platform
Master stereo episodes to -16 LUFS with true peaks at or below -1 dBTP. Here is what each platform actually documents, and where the -19 LUFS mono convention really comes from.
Prefer to check a file right away? Use the free LUFS meter or the ACX check. Subscribe with the RSS feed.