I understand even the best available REQ software/hardware are far from being perfect or effective in most cases. I do believe they are worth considering and hope R&D are still being done for more effective versions for the average users. I also understand the complexity and capability of the human hearing (ears, brains, whatever..), but the effects of REQ are at least highly (okay not perfectly or totally) measurable.
Once upon the time came across an article, a serious one too I think, so hilarious that I had to laugh when reading the part about how a concert grand piano still sounds like a concert grand piano even if put in a room, or any room (don't remember 100% now but something like that..) as one of the reasons why REQ is not need because our ears can tune thing out.... I thought, yeah you can almost say the same about hearing through a home phone handset too. Nay sayers can easily find "reasons" against any technological advance products regardless.
Great thread!
Thanks Peng for joining.
I think the reasons for and against room equalization are complex and nuanced. It’s one of those topics that gets so simplified by so many that the reality is hard to grasp. There is so much BS on both sides of the argument that doesn’t help anyone understand.
I have contacts with most of the major room eq developers and have access to most of the available systems. In my house right now I have Audyssey, DIRAC, YPAO, and ARC. I’ve also had this debate with some of the luminaries (for and against room eq) for over a decade.
My conclusion to date is that both sides are right in a sense. Properly processing the sound and sending it to the right speakers and applying some small amount of eq to the bass is always a good thing to me. I have no problem with that. If the room shows modal effects, smooth them out a little. Across the rest of the range is more debatable. My own experience is that plenty of these systems have made things worse, not better. Some make a measurable difference but any sonic benefit was so subtle nobody could reliably tell.
One thing to remember based on what I discussed in the article, just because it measures better doesn’t mean it is better. Those measurements taken in room have issues. It should make perfect sense that a correction system designed to correct the in room measured response will look better. But if you remember that I mentioned the problems inherent in those measurements, it should also follow that it might not have improved things.
I had to limit how much psychoacoustics I discussed, but there is another issue to consider. Our hearing is capable of discerning very small tonal shifts. However that is only true if the tones played sequentially. If two tones that are very close together are played simultaneously we don’t tend to discern those differences. What that means is that a relatively smooth response is good, but a perfectly smooth response is not necessarily better. That added smoothness may not be audible. Compounded by the fact that some of that roughness is caused by uncorrectable artifacts such as diffraction (again not baffle diffraction).
As for what kinds of future developments are coming. Don’t worry in the slightest. DSP is not going away and I know of nobody in the industry rooting for that. It’s advancing in big ways and what’s coming is a big shift. As I noted in other threads, modern room correction is starting to become real room correction. That is, it’s actually capable of modifying the rooms innate acoustics. Such a system is known as a multi-in multi-out or MIMO correction system. DIRAC will probably be the first to market with such a system, though I understand others are working in similar concepts.
What does this do differently? Well, let’s start with the bass. As the bass travels through the room it begins to bounce off barriers. Normally these are walls, ceiling, and floor. What if every wall had speakers capable of a response down to 50hz covering a portion of its surface at strategic locations. What if the bass signal was split and processed and then sent to each of those speakers such that it mitigates the reflections that cause interference. Depending on the delay and level, you can control modes effectively. So with an ATMOS type system, you already have speakers on most walls. Make sure those surrounds have high output down to 50hz and plenty of power and this is feasible.
What about the mids and highs? Well if you largely dampen the room it becomes possible to change the rooms perceived reverberation characteristics through dsp and the surround speakers. The concept is not new but traditional approaches were pretty bad. By adding special measurements to the equation you can better tailor the effect. The trick remains the need to deaden the room, but it’s actually possible now to actively cancel some of the reverberation in a room.
So basically what is coming is a lot better than what exists now, but also a lot more complex. It puts greater demand on the individual speakers as well. The installer will need to know the speakers dynamic capabilities. Something that is not widely known now. I don’t see this as a diy user installed setup and Dirac has confirmed that this is true. This will be a custom installed packaged system initially.
What remains true with even the most sophisticated dsp correction is that it can’t fix a bad speaker. More attention on the smoothness of the polar response is needed. These correction systems can work more effectively when the polar response is smooth and follows the shape of the listening axis response. The other thing that would help is setup. It’s really important that full bandwidth room correction not be used with systems that have speakers placed such that there are a lot of early reflections and diffraction (and I don’t mean first reflections, which are fine to be left in place). Placing speakers with a table between them, tv within inches of the front of the speaker, etc all cause a lot of reflections and diffraction that ultimately combines with the steady state. Room correction tries to fix this but it’s not fixable.