Axiom Home Page Forums General Discussion Hearing Things Dr Floyd Toole's Talk at Mcgill University

For anyone who is into this quirky pastime, this is an excellent, 'must watch' video that explains so much from 'The Guru' himself. It is not overly technical so even I can understand it all. It surmises why there is so much heated opinion & BS out there, especially on some forums.

https://www.youtube.com/watch?v=zrpUDuUtxPM

Ian wholeheartedly recommends it & summarized the content to me:

Great video. It covers exactly what matters to what we hear and how to make a great sounding speaker. The salient points:

• Listen testing must be done blind.
• The frequency response, as measured all-round the speaker in an anechoic chamber, are what tells us how a speaker will perform in a blind listening test.
• This cannot be accomplished without a proper laboratory to do it in.
• Audible resonances are visible in the anechoic amplitude response graphs.
• Consistency of one speaker to the next in the manufacturing process is critical and rarely done.
• Room correction algorithms will not correct a bad speaker design. They can ruin a good one though.

This kinda dispels some of the 'Myths' that have been spouted in articles elsewhere. One 'Myth' pooh-poohed the notion that a manufacturer having a sophisticated anechoic chamber was advantageous to properly designing speakers. This is laughable. The clear advantage to having this essential equipment is repeatedly reinforced throughout this talk.

From what I gleaned from the video, I am now rethinking my use of Audyssey correction in my HT. Interestingly, Axiom has not recommended room correction EQ use as well...

TAM

Thanks TAM. Great vid. His presentation was much more enjoyable than the paper of the same name. -science in the sevice of art (also very informative). I really need to read his book.

Ok, so maybe someone watched and is thinking "oh no! I own loudspeakers that have issues he highlighted." Its alright, Salon 2s are expensive.

There are a couple of his points that I think were presented as showstoppers, but could be minimised by room treatments. Flat off axis response and a linear directivity behavior are not entirely essential to reference sound (at the MLP). Directivity/off axis problems can be helped by appropriate first and second reflection point treatments. Setting up rooms lengthwise also reduces extreme off axis listening positions.

Also, the timbral contribution of a room at middle frequencies becomes less problematic when treatments are employed and RT60 is reduced to appropriate levels. This increases perceived dynamics and reduces listening fatigue as well.

There are a ton of reasons why an AVR auto room EQ is a bad idea. He hit the nail on the head with a "a microphone doesnt compare to 2 ears and a brain". If you need more convincing search Paul Hales' appearance on home theater geeks. A good one.

I would love to see day 2 of the lecture presentation. Again, thanks TAM.

Both of my rooms are very oddly shaped (one above the other on the second floor) where my systems sit in a large window alcove & fire across the space at about a 45 degree angle.

If nothing else, standing waves & nulls seem to not happen but the mid & higher freqs might be reflecting in a very unique way that might be hard to measure. Who knows??

Anyway, sounds good to me...

TAM

Tom, thanks for linking Dr. Toole's excellent presentation. It was fascinating as he pointed out flaws in many highly regarded(and very high-priced)speakers, including the KEF 105.2 which he specifically named.

You should also consider studying his book "Sound Reproduction", which I've quoted several times here over the past few years.

One of the other points he made was that reviewers are really just reporting on their own adaptability to a sound of a speaker over time, rather than the speakers performance. Very interesting.

I have found this to be true after hearing some of the highly regarded speakers they reported on didnt sound too great to my ears. (KEF Q900 comes to mind.). However one of the biggest let downs I listened to was a "perfectly designed" speaker by Andrew Jones. Maybe I am less able to adapt than others.

I think that it may have been Randy (SirQuack) that said it first, or at least who I remember saying it first, and who knows how good my memory is... Speaker break-in isn't so much as changing how a speaker performs, but giving our ears time to adjust to the new sound of the speaker.

I suppose just to muddy the waters a little bit more on this issue, as part of its design philosophy, "Totem Acoustic" points out that they tune their speakers by ear and don't use an anechoic chamber at all.

Some measurements of their 'Dreamcatcher' model:

http://www.stereophile.com/content/totem-dreamcatcher-loudspeaker-measurements

Despite not being designed in a chamber, many people like them despite less than ideal measurements. They seem to be quite successful in the marketplace. Several people posted that they have a 'house sound' that is not necessarily ideal but pleasing to many.

So again, although measurements are supremely important, it all comes down to personal, subjective preferences on what a person buys...

TAM

I love my Dreamcatchers and can really find no fault with them for 2-channel, casual listening to music in the living room. They are not M80s in terms of SPL or "presence" but they are sweet to listen to nonetheless.

As for comparisons to the M3 and M22, I can only compare them to v2 of both of those models. To me, the M3 sounded "fat", the M22 sounded "thin" and the Dreamcatcher sounds "balanced". It feels like nothing is missing and I don't use a sub. As for price, I don't know - I picked them up as part of a package deal that I couldn't pass up.

My buddy picked up a pair of these for $90 on sale: //www.visions.ca/Catalogue/Category/Details.aspx?categoryId=160&productId=25450&sku=SPBS22LR.

I had these Pioneers in my place for a few weeks. If you take the covers off of these, you have no need for the Dreamcatchers.

My M3s that are placed on stands in 'bass reinforcing' corners in my room also sounded 'fat'. Plugging the port nicely cured that anomaly to where they are very neutral now.

BTW, other speakers sounded 'fat' there also. So it is not the speakers' fault in my case...

TAM