[ACHiPo]

While fairly lengthy, this presentation by Floyd Toole to the Centre for Interdisciplinary in Music Media and Technology, is very interesting.  It discusses speaker design, measurement, and techniques Toole (and Harmon) have developed that have good correlation to subjective listening results.  Highly recommended.

Toole's CIRMMT Presentation

[Tyson]

Really interesting, and I tend to agree with him and his methods. 

But one thing that has always bothered me - if he uses a truly superior method at Harman (and I believe he did), why doesn't Harman have the best sounding speakers in the world?  It seems like a better method would result in very clearly superior speakers, but I've found this to not be the case when listening to Harman stuff....

[poseidonsvoice]

While fairly lengthy, this presentation by Floyd Toole to the Centre for Interdisciplinary in Music Media and Technology, is very interesting.  It discusses speaker design, measurement, and techniques Toole (and Harmon) have developed that have good correlation to subjective listening results.  Highly recommended.

Toole's CIRMMT Presentation

'

Thanks for sharing this.

Best,
Anand.

[Rick Craig]

While fairly lengthy, this presentation by Floyd Toole to the Centre for Interdisciplinary in Music Media and Technology, is very interesting.  It discusses speaker design, measurement, and techniques Toole (and Harmon) have developed that have good correlation to subjective listening results.  Highly recommended.

Toole's CIRMMT Presentation

Thanks for the link - lots of good information.

[rave959]

Thanks for the link - good stuff.


 
Ian

[Rick Craig]

Really interesting, and I tend to agree with him and his methods. 

But one thing that has always bothered me - if he uses a truly superior method at Harman (and I believe he did), why doesn't Harman have the best sounding speakers in the world?  It seems like a better method would result in very clearly superior speakers, but I've found this to not be the case when listening to Harman stuff....

I've not listened to any of their speakers lately. What didn't you like about them?

[Russell Dawkins]

Really interesting, and I tend to agree with him and his methods. 

But one thing that has always bothered me - if he uses a truly superior method at Harman (and I believe he did), why doesn't Harman have the best sounding speakers in the world?  It seems like a better method would result in very clearly superior speakers, but I've found this to not be the case when listening to Harman stuff....

Very good point. I heard Floyd talk about 6 years ago at an AES meeting in Vancouver and felt ultimately that my time was wasted in taking the long ferry trip and the hotel. I found him long on generalities and short on creative specifics. I didn't learn much of anything new (not that I'm any authority) but nothing he said conflicted with my prior understanding. I also found it mildly interesting that he seems to have come to a conclusion similar to Dr Earl Geddes and Duke LeJeune as regards bass reproduction.

During his tenure at JBL, some good sounding speakers were developed, but mainly for the pro studio market. Examples would be the LSR 4300 and 6300 series, the new 7 series and the M2. I'm not sure if he had any direct hand in the M2 Master Reference, but that is highly regarded.

I watched the first 5 minutes of this talk and got the same impression as I did in Vancouver, but will persevere and watch more later when I have the time.

[Tyson]

I've not listened to any of their speakers lately. What didn't you like about them?

Oh, they were OK, but hardly the best speakers around.  That includes several of the reference level JBL's they've been showing at RMAF the past several years.  They all tend toward what I call "wall of sound" type production, where sound is presented in a way that the physical space of different instruments tends to blend together.  "Whitewashed" is always the term that comes to mind whenever I hear one of those speaker designs. 

One thing I think is inherent in his talk, which I wish he'd focus on a bit more, is the importance of the room.  He tends to attack things from the loudspeaker design side, but a lot of the stuff he does with design is to try to deal with less than ideal rooms.  I think the room is by far the largest factor when it comes from deviation from accuracy.  And I think that Geddes with his highly directional loudspeakers and swarm of box subs is one very good method for dealing with this rather intractable variable.  On the other hand, I think Linkwitz with his focus on OB speakers and their also highly directional figure 8 radiation pattern (particularly in the bass) is also another very good option for dealing with room interaction.  And of course room treatments! 

[poseidonsvoice]

...
One thing I think is inherent in his talk, which I wish he'd focus on a bit more, is the importance of the room.  He tends to attack things from the loudspeaker design side, but a lot of the stuff he does with design is to try to deal with less than ideal rooms.  I think the room is by far the largest factor when it comes from deviation from accuracy.  And I think that Geddes with his highly directional loudspeakers and swarm of box subs is one very good method for dealing with this rather intractable variable.  On the other hand, I think Linkwitz with his focus on OB speakers and their also highly directional figure 8 radiation pattern (particularly in the bass) is also another very good option for dealing with room interaction.  And of course room treatments!

The best Tyson in all honesty is when you combine the two. And that is what I have tried to do with my own system (Directivity control along with multiple subwoofers, along with manipulating the room to your liking). It's absolutely an amazing aural experience, every day on nearly every recording. So whether it is Geddes, Linkwitz or Toole, I respect them all and take them all very seriously. And then I create my own. The only problem, is that it can get expensive. But if you are willing to DIY, you can offset a lot of the costs. What one should take home is their research. And I respect that 

Best,
Anand.

[Tyson]

The best Tyson in all honesty is when you combine the two. And that is what I have tried to do with my own system (Directivity control along with multiple subwoofers, along with manipulating the room to your liking). It's absolutely an amazing aural experience, every day on nearly every recording. So whether it is Geddes, Linkwitz or Toole, I respect them all and take them all very seriously. And then I create my own. The only problem, is that it can get expensive. But if you are willing to DIY, you can offset a lot of the costs. What one should take home is their research. And I respect that 

Best,
Anand.

Agreed!  There is no one perfect solution for everyone.  For example, I think all 3 of them would agree that a flat frequency response and even power response are very important. 

But O'Toole embraces a flat, even FR/Power Response with wide dispersion.  Which works well if you are in a large room, a well treated room, or you sit near field.  If you aren't able to enact those 3 things, then I think the Geddes approach of flat FR/Power Response with narrow dispersion is an excellent solution.  And if you are gonna stick with boxed speakers, then multiple subs in a swarm really is the best way to get smooth, even, and detailed in-room bass.  And of course Linkwitz with the OB approach is also quite directional due to the figure 8 dispersion pattern inherent with that design. 

Throw in a bit of EQ to knock down the worst of the bass peaks that are left, and a bit of absorption/diffusion on the walls and you are doing better than 99% of even the audiophile population.

[JoshK]

minor Tangent:  I think where Geddes's and Linkwitz's methods differ the most is on the headroom.   I had this conversation with Dr G at his home many years back.   When Geddes and Lee did their work way back when, they realized that it was highly common for theaters to hit 120db C-weighted.   Dr. Geddes was pretty adamant for including HT and concert videos in the likely source material for his speakers, so the headroom was a requirement.   That excludes Linkwitz's commercial speakers, and barring massive IB sub installations, would exclude OB subs for the most part.    At least, that is how best I interpreted what he was suggesting. 

[Tyson]

OB speakers won't hit 120db at 20hz, but then again, most box speakers won't either.  So a sub is going to be needed regardless.  And if you limit an OB speaker to 60hz and above, transitioning to a HT sub, you should be fine.

But I think the other aspect of your tangent is actually something that's very important and is rarely brought up in the audiophile world - sensitivity.  As I've listened to the very best designs over the years, there is something that highly sensitive speakers bring to the table that mid/low sensitive designs cannot replicate - real dynamics, both macro and micro.  High sensitivity speakers just seem to be able to track the smallest variation in volume as well as scale from 0 to 100 much more forcefully. 

In the past, only "pro" speakers or traditional horn speakers could do that, and they often had poor tonal balance, so you had to choose - do I want nice sounding speakers or do I want dynamic speakers?  One thing I really like about Geddes is he introduced a highly sensitive design that actually sounded pleasant and not harsh. 

I'm not a Geddes fanboy (never even owned a pair of his speakers), but I do think we owe him a debt for helping to break down some of these categories of what a high end speaker looks like and sounds like. 

[JoshK]

I think the disagreement (different solutions) between Geddes and Toole on wide or narrow dispersion is very interesting.    I don't yet have a confirmed opinion.   I am left wondering on the differences in reverb time and room treatment solutions. 

I have even more narrow dispersion speakers 60ºx60º (DSL SM60F) that I use in my HT.   It results, in my room, in a more limited soundstage width, but the clarity, I surmise due to limited reflections, is uncanny, like headphones. 

[Tyson]

I think the disagreement (different solutions) between Geddes and Toole on wide or narrow dispersion is very interesting.    I don't yet have a confirmed opinion.   I am left wondering on the differences in reverb time and room treatment solutions. 

I have even more narrow dispersion speakers 60ºx60º (DSL SM60F) that I use in my HT.   It results, in my room, in a more limited soundstage width, but the clarity, I surmise due to limited reflections, is uncanny, like headphones. 

Absolutely, highly directional speakers have a clarity and crispness that wide dispersion speakers can't match, unless you sit near field, or unless you heavily (and intelligently) treat your room.

This is exactly why I tend to like well designed OB speakers - they also give you that "headphone like" clarity due to narrow dispersion (again, if they are designed well!), but then their rear-wave uses the back wall to open up the soundstage in ways that just are not possible with box speakers. 

But that's just my preference.  I have friends that have box speakers in well treated rooms which sound phenomenal.  They have more treatments than I do, but I think that's your trade off - any room can be made to sound good, if you are willing to invest in a lot of room treatment and are able to apply it intelligently to your space.  Highly directional speakers just let you cheat a little bit and get by with less treatments, IME.

[ACHiPo]

During his tenure at JBL, some good sounding speakers were developed, but mainly for the pro studio market. Examples would be the LSR 4300 and 6300 series, the new 7 series and the M2. I'm not sure if he had any direct hand in the M2 Master Reference, but that is highly regarded.

I watched the first 5 minutes of this talk and got the same impression as I did in Vancouver, but will persevere and watch more later when I have the time.

I'd like to hear the M2s, as I've seen several glowing reviews of them as home theater and studio monitor speakers.  My experience is that monitors often don't image well (maybe what Tyson calls the "wall of sound"), but I'd definitely like to give the M2s a listen.  For $12k they are a relative bargain if they're as good as Toole says.

The full video is a big investment--about 80 minutes--but I really enjoyed the content.  I echo Tyson's comment about the importance of the room--I initially was going to post this in the acoustics circle, but realized it was really more of a speaker presentation.

The $1800 speakers that he references as "nearly perfect" are Infinitys (L60?) that are out of production.  I'm wondering which electrostatic speaker had all the resonance issues?

[JoshK]

Dr. Geddes explained that imaging is often affected by very early diffraction/reflection artifacts, thus the careful attention to waveguide mouth termination and edge roundovers.   That isn't something that is often done in studio monitor type big speakers. 

[Russell Dawkins]

I think the disagreement (different solutions) between Geddes and Toole on wide or narrow dispersion is very interesting.    I don't yet have a confirmed opinion.   I am left wondering on the differences in reverb time and room treatment solutions. 

I have even more narrow dispersion speakers 60ºx60º (DSL SM60F) that I use in my HT.   It results, in my room, in a more limited soundstage width, but the clarity, I surmise due to limited reflections, is uncanny, like headphones.

For the record, I believe that the speakers producing the narrower sound stage are always the more accurate. Narrowness of sound stage cannot be created by speakers; width can.

[richidoo]

Hi Tyson, Harman usually demos their "flagship" speakers with their "flagship" Levinson #53 switching amp. I've heard Everest with #53 once and Salon2 with #53 on a couple occasions - both unbearable. #53 is 4 switching amps per channel, dynamics are like an atom bomb and electrical damping is just too damn high for music. I thought the same as you until I finally had the privilege of hearing Salon2 with Levinson 532, their top linear amp, the real flagship, now discontinued. OMG that was really great. Music came alive and the Salons were great top to bottom. Revel is back on my speaker "to try" list. I also heard the new Performa3 208s with a couple different (non Harman) linear SS amps, that too is a great speaker. Kevin Voecks is a great designer, but system synergy is still important. You'd think an all Harman system would be pure synergy, and it is with their good sounding amps, but #53 should never be connected to a speaker, only Audio Precision tester.  I'd love to hear Salon2s with the new Audio Research GS150 tube amps.
Rich

[Rick Craig]

For the record, I believe that the speakers producing the narrower sound stage are always the more accurate. Narrowness of sound stage cannot be created by speakers; width can.

I would disagree on that. A few years ago I was at an Axpona show in Atlanta and they had  saxophone groups play in one of the large conference rooms. Obviously poor acoustics but the sound was amazing, especially when the largest ensemble perform (20+ players I believe). Some sounds were  spacious / wide with others very specific depending on how the horn projected. In my experience very directional speakers fall short when reproducing this kind of music. The room has to be energized to a degree in order to give you a sense of space and envelopment. With speakers that have a more narrow horizontal coverage I find the sound to be what I call "formatted" in that it's just not as realistic or engaging. Vertical coverage affects this as well but not as much as the horizontal plane.

[JoshK]

For the record, I believe that the speakers producing the narrower sound stage are always the more accurate. Narrowness of sound stage cannot be created by speakers; width can.

In my case, it has a great deal to do with my particular setup and the effectiveness of dispersion control of the speakers in question.  I have an acoustically transparent screen, 109" diagonal, with my speakers behind.  That means my LR width is constrained to about 8' and I sit roughly 12' back.  The LR and toed in so as to not illuminate the side walls.  Thus my soundstage is the width of my screen.   The surrounds greatly open this up, but not for stereo. 

The other interesting thing about the constant directivity speakers I use it that you can't tell the distinction between the front three except for where the sound it meant to come from.  That is, if I were to turn off the center, you wouldn't know it was missing.  There is a ultra cohesion in the front array.   But then these speakers were meant to be able to be arrayed, and that is easily confirmed.   So this gives me some belief that the narrow and controlled dispersion for, at least home theater setups, is the way to go.   

I am building a horn system upstairs, finally (but only after I am finished with the HT setup).  The horns have narrower dispersion than most traditional speakers, so it will be interesting to see how that translates there.   Right now I am just using a pair of planet 10 fonkens upstairs, which are quite nice for background listening.