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Roger Sanders' views on audio: The discussion thread

dallasjustice

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What’s ironic about the Sanders interview:
He has a lot of criticism for other manufacturers who make unsubstantiated claims concerning performance. However, he intentionally designed a speaker with very narrow polar plots at high frequency. The Toole research done at NRC would demonstrate that such a design is inferior to wide/smooth off axis speaker performance.

IME, any salesman who spends too much time criticizing his competitors instead of explaining his product is insecure about his product.
 
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oivavoi

oivavoi

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What’s ironic about the Sanders interview:
He has a lot of criticism for other manufacturers who make unsubstantiated claims concerning performance. However, he intentionally designed a speaker with very narrow polar plots at high frequency. The Toole research done at NRC would demonstrate that such a design is inferior to wide/smooth off axis speaker performance.

IME, any salesman who spends too much time criticizing his competitors instead of explaining his product is insecure about his product.

Personally I like omni speakers, and broke my account some time ago by ordering a pair of omni speakers from Morrison Audio (which I'm still waiting for). That should tell you something. I'm far from being a narrow disperson guy. That said, I'm not 100 sure that Toole's experiments have settled the issue. It might be that wide dispersion will be preferred by a majority of listeners, but does that make it "right" - and does it preclude that other listneres may prefer narrow dispersion?

People like Earl Geddes, for example, who has championed narrow dispersion, and who is more informed on psychoacoustics than most of us - is he simply wrong on this issue? While I like psychoacoustic research, I also think it's important to be aware of the limitations of experimental studies in psychoacoustis. If you compare psychoacoustics to other established branches of perceptual science, it's a small, small field, where many studies/experiments have yet to be replicated.

EDIT: Robert E. Greene writes about this issue in an illuminating way in his TAS review of the latest model from Sanders: http://www.theabsolutesound.com/articles/sanders-model-10e-hybrid-electrostatic-loudspeaker/
 
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SIY

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Personally I like omni speakers, and broke my account some time ago by ordering a pair of omni speakers from Morrison Audio

Is that Don Morrison, the creator of the "umbrella effect" hilarity?
 
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oivavoi

oivavoi

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Is that Don Morrison, the creator of the "umbrella effect" hilarity?

Sounds like the guy! But why hilarious? If the goal is that speakers should disappear completely perceptually, and not sound "like speakers", I think that kind of dispersion pattern probably is the best one.
 

SIY

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dallasjustice

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People like Earl Geddes, for example, who has championed narrow dispersion,
No he doesn’t advocate speakers that beam at high frequency. Earl’s designs very similar to what you currently see from JBL, which is the opposite of beaming loudspeakers.
 
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oivavoi

oivavoi

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The "umbrella effect" was a social experiment. And damned funny. TAC had an article from Morrison about it that described the experiment, the results, and other anecdotes from his time in the business. I was in awe.

Ah, I see. Wasn't aware! Any link or pdf? (the dispersion pattern of his speakers also looks a bit like an umbrella, or rather a mushroom, hence the confusion on my side). He's still in the business, but low-key and completely independent (makes about 16 pairs by hand a year). Here's his website btw: https://www.morrisonaudio.com/

Never heard those speakers, but being a rationalist through and through they seemed to tick all my rational boxes for what speakers should do according to my preferences. So I took a leap of faith.
 
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oivavoi

oivavoi

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No he doesn’t advocate speakers that beam at high frequency. Earl’s designs very similar to what you currently see from JBL, which is the opposite of beaming loudspeakers.

Ok, then I understood you. I'm not sure about this, but: Won't the dipole cancellation on the side largely "fix" this? So that there is little horisontal dispersion - and few lateral reflections - of both low and high frequencies? My previous reading would imply to me that the main problem of beaming etc is that the reflected soundfield (and the lateral reflections) becomes very different from the direct sound. I'm not certain that is a problem with these speakers.
 

Bjorn

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Geddes' speakers do beam to the degree that the polar is collapsing when the horn looses its directivity. Thus the speaker is wide below the horns operation and narrower above. However, it's more loosing its directivity rather than typical beaming. Either way, the result is a difference in the reflected energy.

I've had Geddes speakers by the way. I don't think they are a bad design but I don't think they are great either.

The question about wide vs narrow horizontal dispersion is IMO a matter of taste, depended on the room and the acoustics. But I've never found pure reflective side walls to be bettet than some type of treatment in the long run. This is something I've experienced a lot with, using speakers with constant directivity low in freq.
 
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oivavoi

oivavoi

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The question about wide vs narrow horizontal dispersion is IMO a matter of taste, depended on the room and the acoustics. But I've never found pure reflective side walls to be bettet than some type of treatment in the long run. This is something I've experienced a lot with, using speakers with constant directivity low in freq.

I also think dispersion is largely a matter of taste - but smooth and constant (be it wide or narrow) is obviously superior to ragged and uneven. My own experience is that I prefer more direct sound and less ambiance on non-acoustic studio music, and I prefer more ambiance and reflections on classical and acoustic music.
 

Jakob1863

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No he doesn’t advocate speakers that beam at high frequency. Earl’s designs very similar to what you currently see from JBL, which is the opposite of beaming loudspeakers.

If you look at Earl´s publications he obviously advocates uniform directivity wrt frequency. Of course it is a matter of definition (as always) but of practicability too. A speaker beaming uniformly right from the low end up to the upper end would meet Geddes´ criteria as well as would a omni.
 
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oivavoi

oivavoi

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I’ve never heard that one before.

Earl’s speaker design couldn’t be more different from the great scientist Sanders.

I think your understanding of Geddes' design philosophy might be a bit too shallow. I've been reading lots of his stuff over at Diyaudio, where he's been contributing for many many years. Essentially, there are two things which are really important to him:

- First thing is dispersion, polars, etc. He doesn't want too much reflections, and therefore designed speakers with a relatively narrow dispersion. He thinks that lateral reflections should be avoided, in disagreement with Toole (otherwise he mostly agrees with Toole). But he thinks that room "treatment" doesn't work (again in agreement with Toole), and thinks that it's the job of the speakers to avoid creating too much early reflections. He also thinks that the ambient field should be as similar as possible to the direct sound, hence the importance of power response. The only place he advocates absorbtion is on the wall behind the speakers.

- The other thing which is important to him is volume and dynamics. He thinks that people should be able to play loud.

Hence horns/waveguides, which can have limited directivity, dynamic capabilities and the ability to play loud.

Is this different or similar to the Sanders philosophy? What they share is the view that room reflections on the whole are more bad than good. Both electrostats and the Geddes waveguides have relatively narrow dispersion, and both of them have narrower dispersion in high than in low frequencies.

The main theoretical difference is their view on distortion: Geddes thinks that distortion from loudspeakers isn't that important, people tend not to notice it when it's "mechanic", according to him. For Sanders, low distortion is one of the main design goals, it seems. Also, Sanders says that absorbing the back wave is optional, while Geddes thinks the wall behind the speakers ideally should have thick absorbtion.

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Also, I really don't understand the need for the sarcasm etc. This is audio! This is not that important. And audio is full of designers and gurus who think that all the others are complete idiots, and that they're the only ones who know how to do things. It's part of the fun.
 
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dallasjustice

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I think your understanding of Geddes' design philosophy might be a bit too shallow. I've been reading lots of his stuff over at Diyaudio, where he's been contributing for many many years. Essentially, there are two things which are really important to him:

- First thing is dispersion, polars, etc. He doesn't want too much reflections, and therefore designed speakers with a relatively narrow dispersion. He thinks that lateral reflections should be avoided, in disagreement with Toole (otherwise he mostly agrees with Toole). But he thinks that room "treatment" doesn't work (again in agreement with Toole), and thinks that it's the job of the speakers to avoid creating too much early reflections. He also thinks that the ambient field should be as similar as possible to the direct sound, hence the importance of power response. The only place he advocates absorbtion is on the wall behind the speakers.

- The other thing which is important to him is volume and dynamics. He thinks that people should be able to play loud.

Hence horns/waveguides, which can have limited directivity, dynamic capabilities and the ability to play loud.

Is this different or similar to the Sanders philosophy? What they share is the view that room reflections on the whole are more bad than good. Both electrostats and the Geddes waveguides have relatively narrow dispersion, and both of them have narrower dispersion in high than in low frequencies.

The main theoretical difference is their view on distortion: Geddes thinks that distortion from loudspeakers isn't that important, people tend not to notice it when it's "mechanic", according to him. For Sanders, low distortion is one of the main design goals, it seems. Also, Sanders says that absorbing the back wave is optional, while Geddes thinks the wall behind the speakers ideally should have thick absorbtion.

-----------

Also, I really don't understand the need for the sarcasm etc. This is audio! This is not that important. And audio is full of designers and gurus who think that all the others are complete idiots, and that they're the only ones who know how to do things. It's part of the fun.
The difference between Toole’s recommendations concerning speaker design and Sanders’ is that Toole’s approach is based on real scientific evidence. Sanders’ approach is based on whatever he thinks is best.

Speakers with beaming HF have very little reflective field. This is the opposite of what is desirable for listener preference. In fact, Harman tested an ESL to other types of speakers and it came out dead last.

Earl’s speakers do not beam at HF. His speakers have a smooth and controlled off axis. This is desirable and will result in a better stereo image. To compare ESLs with Earl’s design is really an insult to Earl, IMO.

I have no problem with ESL speakers. But those who live in glass houses shouldn’t throw the first stone. If Sanders wasn’t so critical of others and touting his designs as “SOTA”, I’d ignore him.
 
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oivavoi

oivavoi

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The difference between Toole’s recommendations concerning speaker design and Sanders’ is that Toole’s approach is based on real scientific evidence. Sanders’ approach is based on whatever he thinks is best.

Speakers with beaming HF have very little reflective field. This is the opposite of what is desirable for listener preference. In fact, Harman tested an ESL to other types of speakers and it came out dead last.

Earl’s speakers do not beam at HF. His speakers have a smooth and controlled off axis. This is desirable and will result in a better stereo image. To compare ESLs with Earl’s design is really an insult to Earl, IMO.

I have no problem with ESL speakers. But those who live in glass houses shouldn’t throw the first stone. If Sanders wasn’t so critical of others and touting his designs as “SOTA”, I’d ignore him.

Oh come on. What's up with the hostility? (edit: at least that's how I perceive it, apologies if I mis-read you). I started this thread because I thought it's interesting to rationally discuss the claims Sanders makes in that interview. There is absolutely no need to get worked up. We are all enthusiasts here, just discussing something so supremely unimportant in the grand scheme of things as sound reproduction in the home.

I am fully aware of the listening experiments on electrostats that Toole did, and I am very certain that Sanders is aware of those tests as well. As is Geddes, who nevertheless advocates speakers with a narrow dispersion pattern. If you head over to Diyaudio, I'm sure dr. Geddes would be happy to explain why he doesn't follow Toole's advice on speaker directivity (narrow vs wide directivity). It has to do with the external validity of the tests: What do they tell us, and how far can the results be generalized beyond the tests themselves? What is the outcome of interest? For Geddes, part of the reason he prefers narrow dispersion is that "imaging" has seldom been an outcome of interest in the psychoacoustic experiments that have been done (partly because most of the tests have been done in mono and not stereo). Imaging is one of the most important outcomes of interest to him, and he designed speakers based on what he assumed to be the best way of creating good stereo images.

AFAIK, there have been very few studies which investigate "a better stereo image" directly, so I'm not sure there is that much evidence to back up any claim on the factors that may or may not contribute to a good stereo image.
 
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Jakob1863

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I’ve never heard that one before.

Earl’s speaker design couldn’t be more different from the great scientist Sanders.

I´d like to refer you to :

http://www.gedlee.com/Papers/directivity.pdf

Fig. 9 , page 8 from the pdf

@oivavoi,

just a short note; Geddes only objects to the use of omnis in small rooms for the reasons that you mentioned, i.e. that strong early reflections coming from the frontal plane (in short, so blame just me for incorrectness) could/would make the "imaging" less precise.
In general he has concerns about the colorations due to non uniformly polar directivity (beside the imaging) and as an perfect (or near perfect) omni has a uniform polar map he wouldn´t object _if_ the reflections from the front were down in level or absent or late in comparison to the direct sound.
 
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oivavoi

oivavoi

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just a short note; Geddes only objects to the use of omnis in small rooms for the reasons that you mentioned, i.e. that strong early reflections coming from the frontal plane (in short, so blame just me for incorrectness) could/would make the "imaging" less precise.
In general he has concerns about the colorations due to non uniformly polar directivity (beside the imaging) and as an perfect (or near perfect) omni has a uniform polar map he wouldn´t object _if_ the reflections from the front were down in level or absent or late in comparison to the direct sound.

Good points. I do believe that his thinking has evolved somewhat, though. Here's something he wrote on Diyaudio a while back, which aligns to a substantial degree with my own experience (preferring wide directivity and much ambience for classical, but preferring mostly direct sound for non-acoustic studio recordings):

This is an interesting point and goes directly to a rather lengthy discussion that we had on our local audio clubs forum.

But first let me say that designing a speaker with a DI=0 dB across its bandwidth would be extremely difficult, certainly impractical. I have heard, many times, what are considered "omni" loudspeakers and what I most disliked was their complete lack of any imaging quality.

Which brings me to the other discussion. At its root is ones personal listening taste. We settled on two camps; studio work and field recordings. In studio work there is usually a very solid concrete image created in the studio with no acoustical reference at all. It is created in the studio as a work on the canvas of the loudspeakers and as such it is theoretically possible to have a perfect reproduction of this work. Field recordings, on the other hand, can never perfectly recreate the sound field they record and the best that they can do is to create in the listening space an "illusion" of what the original sounded like. This is sometimes refereed to as the "they are here" versus "you are there" effect.

For studio work playback one wants to recreate the original image and this requires a suppression of the very early reflections and diffraction that mess up this image. The loudspeaker tone should closely match those of the studio speakers and this leads to the "circle-of-confusion" that Toole talks about, but that's another discussion. Certainly no studios use omnis for their mastering.

For field work we know that more room reflections yield a more spacious sound thus helping to create the illusion of being in the large recording space.

These two requirements are diametrically opposed and no loudspeaker design can ideally meet both. For studio work a High DI is desired and the playback room size is not a huge issue. For field work a lower DI (but still smooth and constant) is desirable and the larger the room the better the illusion.

I am a big fan of studio work and hardly ever attend live concerts of acoustic instruments, although I have attend probably 50+ in my lifetime. I find recording playback of field work of the larger venues to be disappointing when compared to the real event. So I can like a live orchestra and not like its recording.

My playback system is ideally targeted at recreating the studio image and so are my designs.

Mono-poles may work very well for orchestral work in a large room, but I neither have a large room nor care to recreate orchestral work.

You need to know where you tastes lie as this is critical to the design of the system that you should choose.

That said, this starts to feel like an exercise in exegesis... there is not too much point in discussing what this or that authority really thinks. That doesn't make it any more true - all arguments and all evidence needs to be critically examined!

But these comments from Geddes are among the most illuminating I've read on speaker directivity, and resonated deeply with my own experience in audio. As a result I decided that I needed two hifi-systems, not one. One will be an omni system which aims at recreating classical acoustic events (which I love) in a reasonably large room, and the other will be a more directional system (the D&D 8C) in a well-damped smaller room which aims at reproducing the constructed & artificial imaging of studio-created popular music (which I also love).
 
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Spirit84

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I am very lucky to have a spent at Roger's home in Colorado. This was about 5 years ago. I would like to paint a mental picture for you as to how he has system setup.
He has an outside car garage which has room to park 2 cars - so it is a double garage with one large garage door - say 18 to 20 feet opening. On the inside of the garage he has placed his speakers to the far right and left - close to where the garage tracks are.
There is a chair placed right in the middle of the empty garage - say about 12 feet in from the opening. So when I was sitting in the chair and with garage door wide open I was looking at the outside (beautiful mountain area).
Then he turned on his system and played some music that I had chosen and some of his favourites. I must confess that what I heard was the most gorgeous stereo sound that I have heard in my 45 years in this hobby. The sound filled the open garage area like a perfect painting. Wall to wall sound - but of course no walls. It was incredible. The last thing that I thought about was so called "beaming". If this was beaming then give me more beaming!
Now my thoughts (in bold). I have eliminated his points that I am not qualified to comment on:
1) "Roger Sanders makes the best loudspeakers in the world".
No one, even Roger, can make this statement. But they are certainly mind blowing

2) "A S.O.T.A. speaker must use an electrostatic midrange".
The reason he provides: "The reason that electrostatic speakers are so good is that they are the only type of midrange driver that has essentially no moving mass. Magnetic speakers simply cannot match the performance of electrostatics in the midrange because they are heavy so cannot be accelerated quickly and accurately at treble frequencies"
The midrange on his speakers are to die for.

3) "Magnetic woofers have many problems with their enclosures that cause them to produce with a lot of overshoot and ringing that makes it impossible for them to integrate well with a massless electrostatic speaker".
See #4

4) "The solution is to use a transmission line enclosure system to virtually eliminate overshoot and ringing in the woofer".
The integration between the electrostatic panel and the TL woofer was impeccable. It felt as if there was no crossover. Roger has spent decades perfecting this method and what I heard far exceeded what I have heard from Martin Logans.

5) "No speaker can be considered S.O.T.A. if it uses a passive crossover. All speakers will perform better when driven by active crossovers and individual amplifiers for each of their drivers".
I use an active crossover in my own system and the diffrence between the built in passive and the outboard active is massive.

6) "Loudspeakers are the most important component in your system. All are seriously flawed. You should put most of your money and effort into getting the best ones you can".
I agree

7) "Rooms interact with loudspeakers to seriously degrade the sound. It is essential to deal with this problem using proper positioning, room treatment, and DSP".
I agree

10) "Digital recording media [and digital playback] is flawless. By comparison, analog is very poor".
Makes total sense

12) "DSP systems are extremely powerful and effective tools. They can improve all audio systems and every audiophile should use them".
[Sanders uses it for crossover and speaker eq, and recommends room correction in the bass but not in higher frequencies]
(Y)
I use a Dspeaker device to contral standing waves in my listeneing room and it has transformed ny system

13) "There is no such thing as too much power"
Reason: "It is easy to show that most speaker systems require about 500 watts to play musical peaks cleanly. Most audiophiles use amps with far less power. Therefore audiophiles are comparing clipping amps most of the time".
(Y - my gut agrees with this. But I would like to see more measurements on this, using the method he proposes with an oscilloscope)

Roger is very adamant about this. He showed me on his 'scope that no matter how loud he turned up the volume, his amps never clipped.

14) "Components that meet the Basic Quality Criteria (BQC) for high fidelity sound always sound identical to each other".
He mentions this as the basic quality criteria: "1) Inaudible noise levels (a S/N of 86 dB or better is required), 2) Inaudible wow and flutter (less than 0.01%) 3) Linear frequency response across the audio bandwidth (20 Hz - 20 KHz +/- 0.1 dB), 4) Harmonic distortion of less than 1%"
(Y)
You either believe that audio is a science or you don't. If it is a science then this must be correct according to Roger.
 
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