AFAIK room correction can only really work in one 'sweet spot', or more sophisticated versions can do some averaged compensation based on several measurement points. As colonel, jagwap and bigshot have alluded to, room correcting DSP can only control the sound until it leaves the loudspeaker, and typically this is just done with phase, time, and EQ correction. If you have control at the individual driver level the way Sonos does, you can do a bit better, but it still doesn't actually "correct" the room. It allows the speaker to compensate for the room a bit. Space still dominates! So in the basic systems with one mic and just simple time/EQ correction, you'll fix a lot of peaks and nulls at the exact location you place the mic. The rest of the room is anyone's guess, could be worse, could be improved. Edit: Back on the actual topic of the thread. I just got a bunch of brand-new, ostensibly identical samples of headphones straight from the factory. I will leave one running pink noise overnight and let you guys know if I hear any serious differences in the morning. I don't have proper measurement gear here so it will by ear, so only really blatant changes are on the table here.
I mean, at low frequencies, you have reasonably large "volumes" of space encompassed by a single wave length, so it needs less precision, but the remainder of your point is sound (hehe).
I find that the automated equalization schemes are fine for creating a jumping off point, but in a home situation where there are variables and compromises to be reckoned with, you have to go beyond that and tune it to find a happy medium for the rest of the room. Unless you are unloved and live alone, of course... Interested to hear what you come up with Zapp. I had the opportunity to compare three different sets of Oppo PM-1s at different stages of use from fresh from the factory to a couple of months in and they were all within very close specs to each other. I didn't detect any burn in change on any of them.
Oh yeah, absolutely, with bass frequencies they might be bigger than your room, but when you're in the Khz range you may find your room is a jungle of nulls, and your ARC only gives you a small oasis of relief from the chaos.
Bass frequencies can still be a jungle of nulls too. Say your room is one half the wavelength of the frequency. The reflected portion is literally going to be the exact opposite of the first half of the wave in a worst case scenario assuming zero phase shift. Pretty much your best bet is room treatment such as bass traps and absorption panels. Without that, DSP room correction is like trying to bail water out of a sinking Titanic with a 5 gallon pail.
Multiple subs asymmetrically placed (usually) address that issue, particularly when phase/distance can be adjusted independently, via DSP room EQ. It may not be perfect, but in a mixed use room where physical treatments might not be acceptable, with some dedication and a decent mic/measurement software, good results are possible. Agree that single subs can be tough, particularly when placement is based on aesthetics and not for best performance. No amount of power or DSP is going to overcome a serious null.
I've read that, but for my room, it seems to work with one powerful sub. I still have a problem with a specific resonant frequency inside the walls, but that is easily taken care of with EQ. I think you need to have open space between the sub and the listener. My sub is line of sight for everyone in the room.
I did the "place the sub in listening position, then crawl around to find the most balanced bass - place sub there." Works pretty good.
So a quick update on burn-in. Left 2 pairs of identical headphones for about 18 hours with pink noise at what would probably be a 90dB listening level. Came back in the morning and tested both against a fresh-out-of-the-carton pair. I found no appreciable difference in frequency or dynamic response. Didn't notice anything with regard to distortion either. Wasn't trying to pull out subtle effects and sit there and convince myself of things over the course of hours, nor did I do any measurements. That said, I am very familiar with this model, with probably 40+ hours of active critical listening on them recently, and more of just passively listening to music. My conclusion is that for this driver anyway, there is no clearly audible effect of a moderate burn-in period. Can't speak to a week's worth of burn-in, nor can I speak to subtle effects, but if you want another anecdote to throw on the "no" pile, this is one.
thanks. it's indeed no more than one anecdote, but I'll still rather gather those than trusting what people remember of the sound a week or a month ago. any removed or better controlled variable is a step in the right direction for me, no matter the result.
