the IMPORTANCE of Break-In ....discuss

Yes, break-in is real, especially with dynamic drivers, not so much with armatures/orthos. A complete change in sound signature should not be expected, but generally, the bass deepens and the treble sinks down a little.

^^ Tyll at innerfidelity did just that with some q701's.  There's a video on his site I believe. 

That doesn't work.

It is a false assumption. There are production variations between identical headphone models. Manufacturers have a range of variation that passes QC. (You'll also find this in almost all electronic parts; resistors and capacitors typically vary +/-10%, so a 100 Ohm resistor might measure between 90-110 Ohms.) Instead of rejecting all drivers that aren't spot-on, they match two closely so they'll be balanced for listening. So one pair might have two drivers matched nicely at one value and another pair matched nicely at a different value. These two headphones will sound different from each other no matter if one is burned-in and the other isn't.

Take a look at the HD-800. I don't know if Sennheiser still offers charts, but they used to email buyers a graph of driver responses for each pair. They really do vary. If the HD-800 varies, you better believe that every other pair does, too. Nothing is as precise as you might think.

And referring to resistors and caps earlier, you better believe that left/right in your amps and sources aren't as precisely matched as you think. They're probably between 5% and 10% off. I hand-matched components in DIY speaker crossovers and I had to buy a bunch of extra parts and spent a few hours measuring and labelling them. I got left and right mirrored to 0.005, but you only get that kind of matching if you DIY or pay for a custom build. Typical audiophile gear won't be matched as closely.

Anyhow, I run every piece of gear right out of the box and have never bothered with burn-in. Everything sounds fine with zero hours on it.

If you don't like the sound signature, don't expect big changes. Not every headphone is for everyone. If you don't like it, you have a few options.

First, either return it or sell it here. Put the money towards headphones you actually like. Unless you've spent a lot of time listening to different models and attended a few meets, you probably don't know what you like yet. Which is OK. This is a learning experience and most people go through a bunch of headphones before they settle in with a pair. If you didn't find the right pair at first, don't worry. That happens to everyone. Almost no one settles down with their first pair. It means you're just like everyone else.

You csn get a slight variation with amplification. If a headphone is almost there, you might be able to get there with a different amp. But don't count on it. It's better to find a headphone agreeable to you.

As a last resort, you can use EQ to change a headphone. But EQ introduces other complications. It's better to find a headphone you like.

But don't count on burn-in to turn something you dislike into something you do like. That's like trusting palm reading or tarot cards for major life decisions. Lots of hokum and very little in the real world.

Yes, as real as the lands of pink unicorns and talking lollipops.

 

I never understood why people let a headphone sound constantly during 100+ hours, with the subsequent problems of heating and the decrease of the life period. Just imagine that a headphone has a theorical life period of 1000 hours, why would I want to reduce it 100 hours for a placebo effect?

If a group of people claim that there's a night and day difference between headphone A after 100-200 hours when compared to stock, then I suppose you could do that. Otherwise, there really is no way to test burn-in as no two headphone drivers are identical. I believe in run-in for shoes, haversacks, clothes, etc. Headphones? They're the same. Over time they wear down and they may start to sound a little different from a new pair. Whether it sounds much better than a new pair, that's up to the listener to decide. My experience with SR60 is that their treble gets less hot over time. Physical burn-in? Psychological burn-in? Couldn't care less.

 

 

 

I think the real way to do it would be to use a single pair.  Measure them out of the box, then burn them in for a set number of hours and compare the two measurements.

I've personally never heard a difference with break-in.  The M50's bass did come out of nowhere within the first hour, but that's the extent of it.  I've no doubt that a mechanical device will change very subtly with hours of use, but in very, very small ways.  Most people seem to make burn-in to be something that magically solves the problems of a headphone, I personally call tomfoolery on it.

I know burn in exists because sometimes it exists and sometimes it doesn't. Actually, most of the time it doesn't. I don't "want" burn-in to work, I'm not a "burn-in fanboy". My Grado cans didn't really change at all over time. Same with Sennheiser I've tried. Obviously it has to do with the drivers used and not the name of the brand, but still. The same goes with most other headphones and IEMs. No armature IEM I've ever used changed over time. The list goes on.

 

However, try telling me that burn-in doesn't exist after you've tried a pair of Panasonic HTF600, or even a KRK KNS 6400. In the case of the Panasonic, there was such a huge change from stock that I initially thought my headphones were defective, since the sound was literally changing in real-time at certain points. It's now settled down to something quite awesome for the price. It's still the same signature, it's not magic, but it's so much less "sloppy", but a little bit of the bass has gone away. I don't like bassy cans but I did like where the Panasonics were with bass before. You're not going to get all positive results out of any natural process; if you do all the time, you're probably making up the results in your head. Also, this only took... eh, about 25 hours total? Maybe 30. Nothing like hundreds of hours. And the KRK changed quite a bit after just 8 or so hours.

 

I have a feeling the "reality" of burn-in relates to how cheaply a product is made. The HTF600 sound stupendous, but being that they sound so good and are still sold for $30 or so, there are some obvious cuts somewhere. I'm sure some of these cuts were in the testing/QC phase -- which also means the drivers didn't get much/any usage before being shipped to the distributor. Money savings everywhere, but it also means greatly varied end-user experiences, and different levels of an effect on burn-in, or just "usage". They are moving devices after all.

All I have to say... Why bringing this up once again? xD I have listened my headphones straight out of the box, and I will do the same with my next headphone when I receive it. = )

 I noticed a very subtle difference in my Grado's treble regions after burn in, toned down a little. It was VERY subtle, but I'm pretty sure it was still there, unless

 a) it was a placebo

 b) I was just "getting used to the sound"

 

 From what I understand, I agree that a small amount of burn-in would help to some extent, but 200+ hours is way over the top. Maybe 25 hours, playing any audio at medium volume. It might make a difference, it might not.