Rule number one with emails/posts/etc. A lot of times one reads and interpret a message different than the one who post it. I can read a post and interpret it a completely different way than someone else.
Buyer Beware: Dennis Foley and Acoustic Fields
- Thread starter James Cohen
- Start date
He seems like a straight shooter, perhaps to direct, but then we don't know the interaction between the customer and Dennis. It is a 2-way street.
Dennis Foley Acoustic Treatment Interview Part 1 - YouTube
Dennis Foley Acoustic Treatment Interview Part 1 - YouTube
Sweeps of frequency response are interesting, but useless to control the acoustic treatment. In order to have a reference for the quality of the work you should have measurements involving time, such as decays, impulse or waterfalls, carried before and after the treatment.
Otherwise, we can't be sure if the perceived improvement is also due to other changes, such as speaker moving or our bias expectations.
My response here is not directed directly to you Micro but to a theme i perceive forming.
First i certainly do not not have before and after measurements. Its in wall treatments during build time . Now what really are measurements going to show vs my ears? I pose the question and maybe this needs to be a different thread, are there gold standard measurements for a listening room, not a studio mind you? I see this thread now having 2 paths. Use him or not (very understandable) and more importantly to me, is my room worth a darn given measurements alone regardless if Dennis did it or someone else. i do want to be clear, am not keen on subjecting my room to an internet based jury based on measurements alone. If folks want to come listen i will be happy to entertain anyone that makes the effort. You can then hear for yourselves. And To that end i dont know any of the professional backgrounds that may be making a determination on measurements nor what a gold standard measurement will actually sound like and more importantly is it pleasing to my ears.
Without measurements there is simply no evidence to support a claim of good or excellent acoustical performance from the room. Human ears are not able to discern the room‘s contributions from the system’s sound from listening. Furthermore a casual listening observation would not provide the information necessary to derive any insight into the quality and acoustic performance of the room.
In any professional project there are specification, or at a minimum design criteria and expectations, that have to be met. Other than aesthetics, were there any technical specifications that the contractor had to deliver?
I suspect that you are not alone and that most acousticians do not provide their clients with acoustic simulations or design specification prior to construction and with “as-built” final measurements of the completed project. The audiophile world is so detached from the realities of the professional world, where contractors have to demonstrate to their clients that the design specifications and objectives have been met prior to signing-off on the commissioning and final acceptance of the deliverables, in order to receive their final payment.
Without measurements there is no way to ascertain the quality and acoustic performance of your room. This in-turn means that there is no way to assess the acoustician‘s work or abilities. Regarding the golden measurements, for one if the contractor was qualified did their job competently then the room response curves should not show greater than +/- 10 dB (A) peaks or dips below 250 Hz. That is not easy to achieve but for one it would be indicative of a good design implementation.
Bruel & Kjaer (B&K) wrote the book on architectural acoustical design back in the 70’s and although there is no industry or gold standard and certified curves for music rooms, there are some pretty good rudimentary guidelines for music room acoustics, in both the frequency and time domains.
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With respect, this is bullshit. The audiophile world has often led the professional audio world and I say that with significant experience in both worlds. I could point to such areas jitter in CD transports, THD in amplifiers, and audiophile cables/power conditioning/grounding products.
Subjectively, one can get a general idea of room sound. Yes, measurements are even better but a good room is pretty obvious.
I guess I should have been clearer, for those like you, by professional I meant the professional industrial business world not professional audio.
Since you been to the room and can subjectively “get a general idea of room sound”, why don’t you enlighten us on how you were able to discern the room’s contributions from the system’s sound and what what your nodal assesment of the room acoustics was in your subjective analysis. If you have any type of feel beyond ”it sounded good” then perhaps we can all learn from your sensory perception.
I’m not sure what industry you worked in before you got into publishing but I can guarantee you that in the science and technology industries “gut feel” does not cut the mustard when it comes to ensuring that what was delivered by a contractor meets or exceed the specifications and design parameters. Conformance testing and receiving inspections are industrial standards. I recently finished work a $7B capital project where every single deliverable had not only certified factory acceptance tested prior to delivery, but was also commissioned and certified post installation by certifying agencies.
Obviously there are extremes, but in the case of work done at home such as on acoustics on a bespoke room, shouldn’t you really want to know what you paid for and what was delivered? The audiophile world is a different beast were hand-waving and inferences can get you a long ways but some of us are not that gullible and demand proof, that we get what we pay for, with hard facts such as measurements and not just a “subjective general idea”.
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Lee,
IMHO such argumentation is a dangerous path. Audiophiles prefer CD transports with significant jitter, amplifiers with all kinds of THD and audiophile cables/power conditioning/grounding products are just experimental products that we must try to know if we like them.
Subjectively we just know if a particular room a good match for a particular system. I found that audiophiles disagree a lot, but room designers disagree even more!
Surely we have some exceptional rooms that most people will immediately say are great rooms, but exceptions do not create rules.
Maybe I misunderstood your intent but having worked in both worlds I can tell you that in several areas, audiophile firms like Chesky noticed the value of hires and implemented it in recordings well in advance of professional recording studios.
For the record my background is in machine learning and predictive modeling so yeah I get the science thing quite well. But I am also intelligent enough to recognize that not all that can be measured matters and that not all that matters can be measured. Audio recording and playback is both art and science.
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Actually most folks with good critical listening skills (admittedly not all audiophiles) can her jitter differences down to single digit picosecond range. The late, great Julian Dunn laid out a strong argument in the 90s that anything approaching nanosecond range jitter would be as much as humans could hear. Later academic researchers found that folks could hear single digit picosecond jitter differences. Dave Wilson once told me that he felt this might have been by design since timing differences relate to survival skills and research suggest they don't actually diminish in listeners until they are well into their 70s!
All the while, several (not all) recording engineers were saying in the 90s that it was just "ones and zeros" and "bits are bits" and audiophiles like Robert Harley were crazy for hearing differences in transports.
Initially the pro world felt that the timbre of a violin could be captured perfectly fine with 16/44.1. Later thinking evolved that 24/96 was really important for capturing violin tone. Indeed some of my intelligent friends think DSD is the way to go.
So for me, I have loads of friends I greatly respect in the pro world and try to learn as much as I can from them. But I also give much credit to folks in the high end business who have done some genuine innovation and have been a bit out front of the pro audio world. I think working together both would be able to accomplish great things.
So in this case nothing is better than something? Because right now we know nothing on these rooms other than “they sound good”. I don’t want to belabor the point but I think that the clients deserve better for their money. To each their own. This really doesn’t effect me personally but since this thread is about giving prospective clients a caution, it make sense to make them aware that acousticians needs to be held accountable for their designs and their implementations in the same way other crafts have to demonstrate conformance and adherence to design specifications and objectives; otherwise you basically get what you get and in most cases the client doesn’t even know what that is. I think that this is all I have to say on this. If you on the other hand, in your role, advocate for the acousticians & consultants and not for customers/clients than that is on you to live with.
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My argument is that the best evaluation includes both measurements and subjective listening.
I'm grateful to the OP for speaking up. I don't care what tone a whistleblower has. And I don't think anyone should conclude Dennis Foley doesn't know anything about acoustical design. They should simply conclude that Dennis Foley is willing to take people's money and not deliver as promised. In Hugh's case, all the heavy lifting was done by Hugh--in an unbelievably impressive way.
The Arizona Corporation Commission Order specifically notes that Foley took these folks' money, bought property, flipped it, then used it to develop acoustical products. He also lived on the rest.
The Arizona Corporation Commission Order specifically notes that Foley took these folks' money, bought property, flipped it, then used it to develop acoustical products. He also lived on the rest.
I'm thinking there is an element of trust not considered in these discussions. As you suggest, many acoustic treatment customers may not grasp what a folder of measurements and graphs is telling them about their space. They will hear what they hear and trust the data correlates to that as they are told by the service provider.
The acoustician should have established bonafides and references. Client sign-off should allow for third party review of before and after measurements or taking a new set of measurements by a third party to validate.
Okay fine. But to whom is the acoustician accountable? A client who does not understand the 'science' behind the work - which is why he's hiring an expert to begin with? Measurements may be one form of accountability but what the client experiences is what really matters. How do the acoustician and customer come to agree on what counts as a result beforehand? Imo, measurement may be necessary but alone it is not sufficient to establish mutually agreed success/satisfaction.
Lee,
Can you point me these studies or even better a link to such publications?
IMHO we should not mix Dave Wilson in jitter argumentation. David specifically addressed analog signal timing, not digital jitter. Jitter does not affect the timing of the signals, just distorts them. The measurements Wilson carry at the factory to establish an amplifier time delay have nothing to do with jitter.
Surely people make all sort of abusive claims in the 90's. But we are in 2021.
The question is more complex than that. No capture system is perfect. At the present moment all we have are preferences and debates. The AES committee in High Resolution Audio seems to be idling, we had an interesting summary paper in 2019 " High-Resolution Audio: A History and Perspective" https://www.aes.org/e-lib/browse.cfm?elib=20455
BTW, IMHO we should always separate capture formats from distribution formats when discussing digital resolution and bit depth.
Surely. But the high-end influence has been mainly in establishing preferences and working around them, an extremely valuable work. Most of them will use measurements in their labs during development and will keep such information private. IMHO innovation goes in pair with measurements.
My feeling is that the high-end has been learning a lot from the professionals - I include scholars and researchers in this category - but I do not see many professionals learning from the high-end.
It would be great, as you say, to have all this people working together, but we do not see it going around.
Microstrip,
The discussion of both jitter and transient playback came up in my meeting several years ago with Dave Wilson regarding the analog signal timing. It is certainly germane to this discussion because it is an example of where the audiophile world led the pro audio world. This also resulted in the development of JVC's glass master process.
Dave referenced some academic research and we actually went through the papers in person. I don't have links to the papers and am too busy running a company to provide the links. I have done this repeatedly on audio fora in the past but nobody ever shifts their opinion in the light of the new evidence.
Again, the references to the 90s are directly relevant here as these are examples of where the audiophile world led the professional audio world.
I am not sure what you mean by capture format versus distribution format. 24/96 PCM and DSD are both capture formats and good ones at that. But they are significantly better at capturing the timbre of a violin (and even bow differences) as I have learned from recording string quartets in Atlanta and New York City.
Lee,
Dave Wilson studied and often referred to propagation-delay noise in crossovers, nicknaming is at "anti-jitter crossover technology" in his designs. It is an analog phenomena, not related at all with digital jitter.
The JVC glass master process is just an example of an interesting but inconsequent audio development - at a time that CD reading transports and mechanisms were extremely sensitive to pit shape and characteristics it resulted in a different (better according to many of us) sound quality.
Here in WBF we had a thread where Gary Koh thought us how to copy our CDs with a selected l burn-in driver, software and media - I tried it myself. They were bit exact and sounded different in some transports, as expected, but had other consequences ...
The pro-word was mainly interested in data integrity, a real problem in the early days of digital.
The papers he has shown you were surely not on digital jitter technology. BTW, language purists objected to his use of the word "jitter" in the audiodiy forum.
As I stated I do not see any led from the audiophile world to the professional audio world in what we have been talking about.
Well, digital recording is much more complex than just 24/96 PCM and DSD. I believe in your experience and findings, but is just says that using the particular hardware you refer there was a significant difference, nothing else.
I am an old time reader of TAS and still own the complete collection starting at issue one and I am a supporter of the high-end audio press. I can see that high-end stereo, mainly due to digital progress, is nowadays much more complex and time consuming than in the early HP days and no one can embrace all areas. Being audiophiles we can learn a lot from other audiophiles. But, although there are exceptions I can't see how audiophiles can led professionals - we are too diverse, individualist and hobby oriented to supply them with trusty and reliable information, something they surely need.
Micro,Lee,
Dave Wilson studied and often referred to propagation-delay noise in crossovers, nicknaming is at "anti-jitter crossover technology" in his designs. It is an analog phenomena, not related at all with digital jitter.
The JVC glass master process is just an example of an interesting but inconsequent audio development - at a time that CD reading transports and mechanisms were extremely sensitive to pit shape and characteristics it resulted in a different (better according to many of us) sound quality.
Here in WBF we had a thread where Gary Koh thought us how to copy our CDs with a selected l burn-in driver, software and media - I tried it myself. They were bit exact and sounded different in some transports, as expected, but had other consequences ...
The pro-word was mainly interested in data integrity, a real problem in the early days of digital.
The papers he has shown you were surely not on digital jitter technology. BTW, language purists objected to his use of the word "jitter" in the audiodiy forum.
As I stated I do not see any led from the audiophile world to the professional audio world in what we have been talking about.
Well, digital recording is much more complex than just 24/96 PCM and DSD. I believe in your experience and findings, but is just says that using the particular hardware you refer there was a significant difference, nothing else.
I am an old time reader of TAS and still own the complete collection starting at issue one and I am a supporter of the high-end audio press. I can see that high-end stereo, mainly due to digital progress, is nowadays much more complex and time consuming than in the early HP days and no one can embrace all areas. Being audiophiles we can learn a lot from other audiophiles. But, although there are exceptions I can't see how audiophiles can led professionals - we are too diverse, individualist and hobby oriented to supply them with trusty and reliable information, something they surely need.
I was at Dave's house and we discussed jitter and how that relates to human hearing. We also discussed propagation delay. The papers were on the latter but David was familiar with Julian Dunn's work and others I mentioned. He did his homework!
Jitter IS a common term among academics. I know this to be true.
As for your DSD comments, this is not true. There are several AES working papers showing underlying theory of why hires is better and there are studies showing the listening improvements from hires in A/B format.
I stand by my earlier comments and as a professional I do know of many instances where both pro audio and consumer audio professionals have learned from each other.
I really appreciate your long-term support of our publication.
