The opinion of ATC to room correction

[fr.jazbec]

Here is a interesting article from ATC to room correction systems

[fr.jazbec]

[SolarMusic]

hi

thanks for the article
i have a room correction system here (acourate) which i used often in the past with good improvements in sound quality (mostly bass)

since the ATCs i do not use it anymore.
They sound good as they are and i have no room problems with my SCM45a.
Maybe, i could have a minimal better sound with using acourate filters again, but it sounds so good, that i do not see a need for it.

[jophill]

This is now a quite old thread but I have been experimenting with mild room correction. The bottom line so far is maybe it has a positive benefit but it does not seem to be that big a deal for me in this listening room. That seems very much in line with SolarMusic's experience.

Measured with REW, my room is quite well damped with a few anomalies. In particular there's a boost from the 26 Hz mode from the length of the room and a couple of other features including one suck-out, probably from speaker - boundary interference. I have been really enjoying SCM50As in this room for several years without any correction.

I think the arguments put forward in the ATC material above are good. And Floyd Toole's book on Sound Reproduction describes experiments which confirm that people very quickly learn the audio characteristics of their room and compensate, to ultimately "hear through the room" to primarily perceive the quality of the loudspeakers. However I have definitely heard bad rooms where a mode has been so dominant that I could not ignore it. I suspect human adaption to room acoustics has some limit.

So I have been trying some very mild parametric correction to flatten my two main "boost" features, ignoring the primary suck-out. Mainly I listen to broadcast classical music and recordings where I know the sort of sound I expect from the source. There is a difference. I don't have a clear description of the change - other than that the volume I perceive is slightly reduced and I compensate for that with a slight tweak on the volume control.

I have listened with correction for a few weeks and probably I will take it out and see if I miss it. However I suspect not. It seems that ATC's loudspeakers play well with the room, at least according to my ears.

[SolarMusic]

less volume after applying filters is normal.

With my older speakers (active Backes&Müller BM18 and BM4) the highs were a bit harsher than with the SCM45.
that's why I benefited more from the filters, which had lowered the highs a bit. (3db over the entire frequency spectrum)
The ATC fit right in the highs and mids for my taste.
I can also fine-tune it a bit with the equalizer in roon, which is very good. But I turned that off for now.

[jophill]

I have been trying to understand whether room equalization is one of the audio industry's "emperor's new clothes" innovations or not. It gets good press but currently I am on my second try of some simple room EQ after having, like SolarMusic, turned off my last try and not missed it.

From listening and from reading engineering-led material (including ATC's opinion as posted above by fr.jazbec) my current thoughts are that EQ has some benefits but is probably being over-sold to the non-professional buyer. My hypothesis is that equalization:

• [benefit] applied to an already reasonable loudspeaker by its maker to flatten its anechoic response can make it better. I think some professional loudspeakers do this. I suspect you need no better than the flatness given in ATC's opinion and that can be achieved by a good maker without EQ.
• [no benefit] applied to a loudspeaker with a poor directivity is not likely to improve that. Good directivity is a fundamental design essential for a loudspeaker to work in an untreated room to allow early reflected sound to tonally blend well with direct sound.
• [some benefit] applied to a good loudspeaker in the low bass region only to deal with the room, or applied to sub-woofer(s), is probably effective but may damage the direct sound that dominates human audio experience if applied at too high a frequency. I think this trade-off may help in a bad room but it's probably preferable to fix the room's problems if possible.

I wonder if I am being too sceptical. I wonder if I should try harder to EQ more than just the couple of biggest anomalies in my in-room frequency response. I am open to suggestions.

I have just now turned off my recent EQ and I will see again if I miss it over the next few weeks.

Regards
John

[Mariner]

Since the modern furnished apartments are usually very sparsely furnished and a cool, straight-line design is state of the art, the acoustic quality has usually deteriorated. Also the technical possibilities for room correction have improved, this is of course also used and can certainly be sold well. There were also times when tone control on HiEnd amplifiers was a nogo. Basically, I would say that setting up the "listening room" is very important and has a decisive effect on the subsequent listening pleasure. An electronic intervention to improve the room acoustics is always just a makeshift crutch to solve the problem. If there is no other way....okay. But for me, measures in the room itself would always come first.