r/audioengineering • u/UnfairWorldliness882 • 1d ago
Mastering Using old CD's are reference
Can someone explain to me this.
Why the era/format also matters
A 1992 CD master was made for Red Book CD, a fixed 16-bit PCM format with no lossy transcoding step and no concept of "true peak" as a mastering concern at all — true peak/inter-sample overs only became something engineers cared about once lossy streaming codecs (MP3, AAC) made it a real audible risk in the 2000s–2010s. That +0.03 dBTP result isn't the 1992 engineer making a mistake or taking a risk — it's simply a number that had zero relevance to their format, so there was no reason to control for it. This CD rip isn't a broken master; it just predates a concern that didn't exist yet for the medium it was built for. Applying today's dBTP/streaming standards backward onto it doesn't tell you anything about your own file's target.
Yes, I know, I am a bad boy for using AI to help me master but I am trying to figure out if I am going down the wrong rabbit hole when comparing my work I am doing in 2026 to something that was made and manufactured in the 90s? Is it a waste of time to use old CD's pre-2000 or pre-2005 as reference?
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u/dmills_00 1d ago
Actually, it mattered even then because the early oversampling DACs were often short of headroom for the inter sameple peaks.
Lossy codecs made it significantly worse, but you could clip the older DACs in the digital domain.
Now (Mostly) nobody was thinking that way back then, and it was the height of the loudness war at least in terms of the tech of the time.
Nothing wrong with using an old CD for reference, if that is the sound you want, but I would indicate that listening for a reference SOUND is different to paying attention to a LEVEL, and the sound is the meaningful one to attend to.