Romy The Cat idea about Room Acoustics:
I do not believe in acoustic treatment for low frequency, unless you do monumental architectural changes in your room. The existing acoustic treatments do very unproportional treatment as very effective and a higher frequency. So, when you use them to treat your 100 Hertz they make reverberation time at 1000 cycles much shorter than you would like it to be as they're much more effective at higher frequencies. So, for 10% of correction 100 Hertz you create 300% damage at 1kHz. To treat some corners, VERY moderately it still might be OK but it is about it. My approach to dealing with the problem like this is very different and I I have written a lot about it.
This statement is so general that it becomes intrinsically false. Unless we have all the details it just introduces noise in any decent discussion about room treatments. BTW If we want discuss room treatments we should focus on the proper way of doing them, not just enumerating the problems of a few anecdotal cases - every one is an expert on negatives.