[poseidonsvoice]

By Dr. Floyd Toole: https://www.audioholics.com/room-acoustics/room-reflections-human-adaptation

 

Best,

Anand.

[Odal3]

Thanks for sharing. Enjoyed the read

[JLM]

Reading his entire book, "Sound Reproduction" makes digesting this article quite a bit easier. 

Anyone pursuing design or setup of a listening room should really read the book for themselves.

[poseidonsvoice]

Reading his entire book, "Sound Reproduction" makes digesting this article quite a bit easier. 

Anyone pursuing design or setup of a listening room should really read the book for themselves.

Indeed. I think owning his book is imperative if you are serious about improving your listening experience, and dare I say it, manufacturers should read it as well!

He condenses a lot of his book in the 30 page publication titled "The measurement and calibration of sound reproducing systems." It's available as a free download here: https://secure.aes.org/forum/pubs/journal/?ID=524

Best,

Anand.

[DaveC113]

I like this summary:

And Now, What “Toole” Really Believes:

By now I hope that readers have concluded that the matter of early reflections in rooms is not a simple one. There is no single “right” way to do things. About 37 years ago, when I was setting up the NRCC listening room, I ran a drapery track down the front portion of the side walls and across the wall of the room behind the loudspeakers, hanging 4-foot sections of densely-folded heavy drapes. The track was about 6 inches from the wall for good broadband absorption. These could be moved around, and in the case of the sidewall reflections, we quickly found that things sounded better if they were pushed back for more "spacious" classical music, and pulled out for "in your face" rock/pop stuff. I knew a couple of stereo enthusiasts who copied the idea at home. I concluded that, in terms of loudspeaker/room combinations, one size does not fit all. I believe it still to be true, but now we know a lot more about the factors that influence our opinions. Given the enormous variations in recordings, the absence of useful information on most loudspeakers, and the uncertainties of loudspeaker/room interactions, there can be no absolutely predictable outcomes. However, as has been found in many situations, human adaptation seems to save the day.  We tend to get used to what we have, up to a point.

Especially the last sentence. I believe a lot of data taken over the years, as helpful as it is, is also colored by acclimation to listening to typical dynamic speakers in relatively small, reflective spaces. It takes people some time to re-acclimate to sounds that are different than what they are used to. Sometimes this doesn't take long, other times it can take some minutes... And when you switch between a typical dynamic speaker and one with narrower directivity it sounds odd for a while, no matter which direction you switch to. The wide dispersion speaker sounds a bit odd after listening to the narrow dispersion speaker and vice versa.

I've been doing a lot of speaker testing lately, including preference testing. While my results are extremely consistent, the comments people make and the things they notice and say are important to them can be very different. Yet the overall preferences are never different.

In the context of a good recording that includes spatial information from the space it was recorded in, or masterfully added later, there IS a significant difference that everyone notices. A wide dispersion speaker with more reflected vs direct sound has the effect of bringing the recording into your listening room, which is great and what most people are used to hearing. BUT, the narrower dispersion speaker is capable of transporting you to the recording venue, which is different from recording to recording. Your listening room is always the same. If people are given enough time to acclimate to the differences of sound due to dispersion, most of them notice and articulate this difference in some way and they all seem to prefer the narrower dispersion speaker that allows them to hear the sound of the space in the recordings much better. It provides for a more immersive, 3 dimensional and larger soundstage that extends well beyond the boundaries of the listening room.

Then, there is also the fact that the narrower dispersion speaker is avoiding first reflections by design, so the dependence on the room acoustics is significantly reduced. This means you can put the narrower dispersion speaker in a typical untreated living room environment and get much better results vs a wider dispersion speaker.

[Odal3]

That book has been on my to read list for a while. I have always found this topic very interesting. I'm just starting out learning more so what other more "researched" based books and authors do you recommend?

What about this one?: Peter Damaske, Acoustics and Hearing

[poseidonsvoice]

Odal3,

Here is one strongly recommended by Andrew Jones:

http://www.amazon.com/gp/aw/d/0123914213/ref=pd_aw_sim_14_1?ie=UTF8&dpID=51bj0YTZ3nL&dpSrc=sims&preST=_AC_UL300_SR300%2C300_&refRID=1RESN80KQR73WADPW8XC

Best,

Anand.

[Odal3]

Thanks! They sure know how to charge for these books.$114 from Amazon. Reminds me of University course books.

BTW: The book by P. Damaske I mentioned was recommended by S. Linkwitz (the other one he recommended in the article I read was the one by Toole already referenced in this thread)

[andy_c]

Odal3,

Here is one strongly recommended by Andrew Jones:

http://www.amazon.com/gp/aw/d/0123914213/ref=pd_aw_sim_14_1?ie=UTF8&dpID=51bj0YTZ3nL&dpSrc=sims&preST=_AC_UL300_SR300%2C300_&refRID=1RESN80KQR73WADPW8XC

It's a great Acoustics textbook for people with EE, Physics or Math degrees, but it's not something for lay readers like Toole's book is.

Interestingly, Beranek's first acoustics textbook was published in 1954.  He is 101 years old!