CMP Mixing and Mastering Principles 2 — Questions and Answers
Question 1: What is the primary purpose of mid-side (M/S) processing in mastering?
- To apply different EQ and dynamics to the center and sides of a stereo mix independently (Correct answer)
- To combine two mono tracks into a single stereo output
- To remove low-frequency content from the stereo field
- To convert a stereo mix to mono for club playback
Correct answer: To apply different EQ and dynamics to the center and sides of a stereo mix independently
M/S processing decodes a stereo signal into Mid (mono sum) and Side (stereo difference) components, allowing independent processing of each.
Question 2: Which bus compression technique is commonly used to glue elements of a mix together?
- Parallel compression on a send channel
- Inserting a compressor on the stereo master bus with a slow attack and fast release (Correct answer)
- High-ratio limiting on individual drum tracks
- Sidechain compression triggered by the kick drum
Correct answer: Inserting a compressor on the stereo master bus with a slow attack and fast release
A master bus compressor with slow attack (allowing transients through) and fast release helps unify the mix's dynamic feel without killing punch.
Question 3: What does the term 'true peak' refer to in digital audio metering?
- The loudest RMS value averaged over one second
- The peak level that accounts for inter-sample peaks that may exceed 0 dBFS after D/A conversion (Correct answer)
- The peak level measured before the master limiter
- The maximum LUFS value allowed by streaming platforms
Correct answer: The peak level that accounts for inter-sample peaks that may exceed 0 dBFS after D/A conversion
True peak metering oversamples the signal to detect inter-sample peaks that can cause clipping in D/A converters even when the digital waveform shows values below 0 dBFS.
Question 4: In mixing, what is the purpose of high-pass filtering (HPF) on most non-bass instruments?
- To add warmth and low-end body to the instrument
- To remove inaudible or muddy low-frequency content and reduce mix clutter (Correct answer)
- To increase the perceived loudness of the instrument
- To create a send effect for reverb tails
Correct answer: To remove inaudible or muddy low-frequency content and reduce mix clutter
HPF removes unnecessary low-frequency rumble and buildup from non-bass instruments, keeping the low-end clean and focused.
Question 5: What is 'parallel compression' (New York compression)?
- Compressing a signal and blending it with the dry, uncompressed signal (Correct answer)
- Applying two compressors in series on the same channel
- Using sidechain compression on a parallel send bus
- Automating compression ratio changes in real time
Correct answer: Compressing a signal and blending it with the dry, uncompressed signal
Parallel compression mixes a heavily compressed version of a signal with the original dry signal to retain transient energy while adding sustain and body.
Question 6: When mastering for streaming platforms like Spotify, what integrated loudness target (LUFS) is typically recommended?
- -6 LUFS
- -14 LUFS (Correct answer)
- -23 LUFS
- -3 LUFS
Correct answer: -14 LUFS
Spotify normalizes playback to approximately -14 LUFS integrated, so mastering near that target avoids unnecessary gain reduction or dynamic loss.
Question 7: What is 'frequency masking' in a mix and how is it addressed?
- Masking is a desired effect created by reverb tails overlapping
- It occurs when two sounds occupy the same frequency range, causing one to obscure the other; addressed by EQ carving (Correct answer)
- It refers to noise floor suppression using a noise gate
- It is the process of automating mutes to hide bleed between tracks
Correct answer: It occurs when two sounds occupy the same frequency range, causing one to obscure the other; addressed by EQ carving
Frequency masking happens when competing elements share the same spectral range; EQ cuts on one element create room for the other to be heard clearly.
CMP Mixing and Mastering Principles 2
What is the primary purpose of mid-side (M/S) processing in mastering?