Here's another one for you. Hours to weeks in some cases.
The loudspeakers used in speakers are complex mechanical parts which require a running in period in order to work to the best of their ability
www.focal.com
And they are right, it takes a good period of time and at high levels with a lot of bass in some cases, same applies to headphones.
If you can't hear the difference from none broken in high end speakers or headphones, it means they are not for you and you wasted your money on something you can't hear the difference with. I hear how bad some speakers and headphones sound when new till they are broken in right and for sure after the break-in if they still sound bad they go back for a refund.
They're not right, they're lying. This is because focal are a speaker manufacturer, they have a big financial incentive in making you believe it takes that long (because doing so reduces returns/refunds). If you believed them, I have a bridge to sell you.
Find an independent source (not someone with a financial incentive in convincing you it takes a long time) that has taken scientific measurements to prove what they say (like the guys at audioholics did, and concluded it takes minutes not weeks) and I'll be interested. The differences you are hearing are called observer bias (
https://en.wikipedia.org/wiki/Observer_bias), the sound isn't changing, you're just getting used to it, either that or your speakers are faulty. Always double check what you hear with a calibrated measurement microphone.
Andrew Jones explains speaker burn in, and how speakers change over time.
I've interviewed Andrew Jones a number of times, but we never discussed speaker burn-in, now we have. Hope you enjoy it! In the Andrew Jones interview Part 2...
www.youtube.com
ELAC's Andrew Jones addresses questions about how speakers age, do they wear out?Here's Part 1 of the interview, Do speakers change after "burn in"? https:...
www.youtube.com
I'm not posting the above for yourself, but the people in this thread that don't believe speakers change over hours, days or even years.
AJ gives a great and in-depth explanation of what exactly burn-in is and how it happens and its effects, but nowhere in either of these videos is he specific as to the timeframe (I suspect this is deliberate on his part), other than saying "less than 100s/1000s of hours" or words to that effect (near the end of the first vid).
The previous link you posted (
https://www.audioholics.com/loudspeaker-design/speaker-break-in-fact-or-fiction) is more informative on this topic, it includes numerous technical details, formulas, and most importantly they present
evidence. Nothing anyone says is worth a crap without evidence to back it up. And that evidence is consistent with my initial assertion, break-in takes minutes only and almost certainly happened during QA for the driver/speaker. Nobody has yet presented evidence to the contrary (Focal's marketing blurb does not count as evidence, sorry).
Interesting (unrelated) point in the second video: around 7 minutes in AJ confirms that an under-powered amp driven to clipping CANNOT fry a speaker coil, correcting a common misconception that tons of audiophiles make. I'll have to bookmark this for future use. Thanks for linking these vids.