Thanks for doing this Amir. I agree a calm on-point discussion is always the best approach. One thing I didn't see mentioned in your lists is that the size of the room also affects the treatment strategy. The ideal treatment for a 25 by 35 foot great room is very different than for a 10 by 12 foot bedroom.
Originally Posted by amirm
1. What is the priority order? Room response is different below 200-400 Hz than above. So clearly strategies and impact are different.
It's all important. The only reason to begin with this versus that is when someone can't afford to treat everything all at once, and so has to start somewhere. I used to say start with bass traps, but these days I suggest starting with reflections since that affects clarity over a larger range of frequencies.
2. Reflections. What and why to treat.
You missed and how
to treat. Why treat? To avoid echoes and comb filtering that muddy the sound.
3. Multi-use rooms. Do they need purpose built acoustic treatment? How can we tell if they need anything at all?
rooms benefit from some amount of treatment. I've never seen a room that would not benefit. If it's very small the bass range is a big problem. If it's very large there's too much reverb.
4. Speakers. That is the thing that excites the room. Surely it matters what it does relative to our optimization goal here.
All speakers are different, and flawed in some way, and people's preferences are a factor. So I mostly stay out of that.
5. Different acoustic material. Why use one vs the other? And performance within types.
Cost baby, cost.
6. Pro/recording/mixing studio practices vs home. How applicable are they to home use? Do we hear like they do and have the same needs?
Yes, same goals and needs. I see no functional difference between a recording studio control room and a home listening room.
8. Measurement systems to figure out what to do. Analysis tools exist that show what happens in "time domain" as you spike the room, and watch what comes back. The counterpart to that is frequency domain where we see the familiar frequency response chart. Which should be the tool of choice and why?
A waterfall plot shows both. I use that for bass frequencies, and 1/3 or 1/6 octave averaged plain response for mids and highs. Those two graph types, plus RT60 by third-octaves, tell all that's needed, though an ETC can help identify where
problem reflections might be coming from.
9. Electronic correct; automatic and otherwise. Are they better than we think they are or worse? What problems do they solve? And what problems can they create?
I'm okay with using EQ to reduce the one or two worst peaks at very low frequencies. Any other application of room EQ is misguided IMO.
am of course!
I sat through two separate training sessions at CEDIA. One by Dr. Toole and another by one of the most popular theater designers. The latter's advice at times conflicted what Dr. Toole said. When I asked him about it, he simply said they disagree.
There is an art to room "setup" (all things related to the room's acoustics), but in the end the goal is always the same: A flat response with minimal ringing and echoes.
11. What is the science that guides us here?
Programs like Room EQ Wizard reveal all of the problems.
12. What are the definitive references so that when we are invariably challenged, we can put forward authoritative data that says we are right beyond our opinion? Can we agree on what that is?
Toole's latest book, and my latest book.