The root of audiophile myths (and how we fell for them)?

[JRS]

I used to train new technicians in a specialty field, years ago, and the one thing I found needed the most work was my own assumption that people knew what I was talking about as I explained things. That got brought up short one day when one of my trainees asked: "What's a voltmeter?" It's strange how we think we're doing such a good job and get stopped dead over such simple omissions... I mean, heck, everyone knows what a voltmeter is... right?

What you guys are doing is great... What I had in mind when I made my comment was the really basic stuff like what frequency response is or what impedance means and so on. Not how they impact performance ... what they actually are.

Anyway guys keep up the good work... love both your channels.

It certainly can be frustrating and eye opening. I recall opening a microbiology course to nursing students, not with the traditional lecture that is dry and is mostly definitions, but with a more topical and general discussion on superbugs and the threats posed by antibiotic resistance. I thought the lecture was easily YouTube worthy, and should have at least opened eyes for this looming threat, and the carelessness that causes it. Following week very basic questions I figured a bright fifth grader could handle on a pop quiz. The majority of the class failed miserably. Since then, have dialed back expectations and repeat everything of importance 3 or 4 times. The classes are duller, and larbely rote, but at least they know that some bacteria are very bad, handwashing is a good, and taking only half the pills is a very bad idea. It takes a lot of grit to teach in our overstimulated, can't really multitask though I think I can world.

 

[Deleted member 46664]

It certainly can be frustrating and eye opening. I recall opening a microbiology course to nursing students, not with the traditional lecture that is dry and is mostly definitions, but with a more topical and general discussion on superbugs and the threats posed by antibiotic resistance. I thought the lecture was easily YouTube worthy, and should have at least opened eyes for this looming threat, and the carelessness that causes it. Following week very basic questions I figured a bright fifth grader could handle on a pop quiz. The majority of the class failed miserably. Since then, have dialed back expectations and repeat everything of importance 3 or 4 times. The classes are duller, and larbely rote, but at least they know that some bacteria are very bad, handwashing is a good, and taking only half the pills is a very bad idea. It takes a lot of grit to teach in our overstimulated, can't really multitask though I think I can world.

Well I've got a few of the pages onlilne ... check my signature.

And yeah, I had to dial it back alot, especially during that first week when all you can really do is talk.

I also noticed that over the course of time my "new hires' were getting a little (ahem) less intelligent. The first few courses I taught everyone had some basic underpinnings... Ohms Law, Watts equations for power, voltage, current, resistance, etc... and things went along famously. I was even able to give a long weekend at the end of some courses. But by the end of it, I was getting students who didn't even know how to use a screwdriver. My final course started with "Okay, everybody, phones and music players off... This is a piece of wire..." Yeah...

 

[Doodski]

Well I've got a few of the pages onlilne ... check my signature.

And yeah, I had to dial it back alot, especially during that first week when all you can really do is talk.

I also noticed that over the course of time my "new hires' were getting a little (ahem) less intelligent. The first few courses I taught everyone had some basic underpinnings... Ohms Law, Watts equations for power, voltage, current, resistance, etc... and things went along famously. I was even able to give a long weekend at the end of some courses. But by the end of it, I was getting students who didn't even know how to use a screwdriver. My final course started with "Okay, everybody, phones and music players off... This is a piece of wire..." Yeah...

We attended different electronics studies. I studied in BC. In the first day we covered 4 large chapters and where assigned another 3 chapters to read overnight for the next day. I figured it out to be about 1000 pages to 1400 pages per two months of study plus a lab book for each of the hard cover text books. So it was electronics theory in the morning and after lunch it was labs. Those instructors did not mess around and they ensured no matter how painful it was for me that I would learn. Within 5 minutes of the first day I knew I was in for a very fast paced and dense course structure.

 

[JRS]

Okay I have given the question posed in the thread title some thought and I think there are two roots to audiophile myths, and that they symbiotically combined.

Firstly by the 1980s most;/all of the big names were producing well-made, reliable and well measuring products. Magazines were doing mostly factual reviews back then so this posed a problem of how to differentiate your product in the marketplace. This was a big problem for the salesman.

Secondly in any area where subjective appreciation is the end game (food, drink, literature, the performing arts etc) there are always going to be people who consider themselves to be extremely discerning, above the average.

There was some sort of symbiosis between the salesman looking to flog his 'me too' product in a crowded market place and the people who reckoned they could hear differences where none should really exist. and the result was the totally subjective review.

Measurements no longer mattered and now what sold was what had the best story. You can see why salesmen welcomed this.

Certainly it started in the high end mags but by 1990 it had pretty much become the norm in all of them.

The review should start with some sort of eulogy about the manufacturer and their 'passion'. Then if possible move on to the designer who should ideally have a background in an activity that is both macho and scientific/engineering - racing hovercraft at NASA, something like that.

Try to make out there's a bit of a cult around him 'In the Industry'.

Then move onto the advanced technology in the product - easy part this, just copy and paste from the brochure.

(If this is a high end mag then don't forget that you really need to mention your wife at least once at some point in the review. You should also mention at least once another thing that you are also a connoisseur of - watches, vehicles, wine etc).

And then onto the 'Sound quality'. Begin by describing what you have in place already and how fantastic it sounds, and then - after warming up, burning in and letting it settle - you start the listening with the new component.

This is where you start writing about 'how you felt' when you listened to the equipment, and that what Coltrane was doing with his breathing through this Kenwood did not sound the same as it did through that Marantz - and so on

For everyone of that generation we started listening in that way too because that's what we learned from the reviewers was the way to do it. The occasional old-timer who would pop up to say 'It's all in your head lads' was dismissed as not knowing anything.

That's how the myths started.

Maybe we read different rags, but I picked up the Stereophile habit round 86-87 IIRC. The message was McCantz and Sansewage were for tin eared cheapskates, and a budding audjophile should be shopping Luxman or in a pinch NAD while saving for entry level Audio Research or Conrad Johnson tube gear. Sam Tellig was the only one to recommend 3 figure products. With luck some of these even received a C on the recommended component list that one could purchase without shame, and a confessional with your local priest. Speaking of priests, these self proclaimed golden eared wonderkind and the whole process of monthly annointments is more than a bit reminiscent of a religion.

 

[JRS]

Well I've got a few of the pages onlilne ... check my signature.

And yeah, I had to dial it back alot, especially during that first week when all you can really do is talk.

I also noticed that over the course of time my "new hires' were getting a little (ahem) less intelligent. The first few courses I taught everyone had some basic underpinnings... Ohms Law, Watts equations for power, voltage, current, resistance, etc... and things went along famously. I was even able to give a long weekend at the end of some courses. But by the end of it, I was getting students who didn't even know how to use a screwdriver. My final course started with "Okay, everybody, phones and music players off... This is a piece of wire..." Yeah...

Thats a real phenomenon, or at least the private for profit colleges you see in strip malls. First couple of years, you get decently qualified students and a real diamond in the rough or two in each class. Two or three years later, the market has been tapped out, and oh lordy do you get some doozies. I finally quit teaching--the salary is piss poor but it's a labor of love until it isn't.

 

[Deleted member 46664]

We attended different electronics studies. I studied in BC. In the first day we covered 4 large chapters and where assigned another 3 chapters to read overnight for the next day. I figured it out to be about 1000 pages to 1400 pages per two months of study plus a lab book for each of the hard cover text books. So it was electronics theory in the morning and after lunch it was labs. Those instructors did not mess around and they ensured no matter how painful it was for me that I would learn. Within 5 minutes of the first day I knew I was in for a very fast paced and dense course structure.

Yeah I got that at NCAAT when I was learning.
What I taught was a very hands on industrial course. My job was to give them the basics of board swapping in a rather short time and then they would apprentice with one of our established technicians... So it was more like "Okay lets pull this apart and see if we can put it back together..."

 

[JRS]

Exactly. I get the logic behind the knuckle test but it's not going to present a thorough enough argument whether the problem is going to be acoustically effected in a negative way or not. As long as you don't put all your eggs into the knuckle test basket then it's an okay test to give you one metric of the design. But then again is your brain going to be keying in on the fact we view a failed knuckle test as bad then it may bias your decision during the listening test. I suppose as long as you hold off on the knuckle test until after the listening tests?

On a somewhat serious note:

I always assumed it was a poor man's Dirac impulse response--strike it hard and fast to see what resonant frequencies are excited, theory being these will bleed through with broadband excitation. Better than kicking a cars tires for road worthiness, or so it seemed.

I imagine this too is something seen then imitated. And that using mass is the unimaginative path to lowering resonance, a more enlightened path is to make stiffness the goal--much more elegant to increase panel stiffness by using composites than adding mass that needs to be schlepped about. And of course keeping the constrained dimensions small, resonant frequencies high where there is little energy to excite them. Long story short a click or ping is better than a thud in many cases, or is this all woo-woo as well?

 

[Newman]

The knuckle rap test has a couple of things in common with the square wave test:-

1. it is useful and informative, if you know enough about its relation to audibility during music playback
2. a ‘better’ result is often not related to audible superiority…so it is misused/overused by people who don’t ‘know enough’

IMO the ‘hand on speaker playing music’ test is less misleading than the knuckle rap, but still somewhat misleading, since one can probably feel vibrations that are audibly masked.

cheers

 

[NTK]

Dr. Toole's post, I think, takes a bit of familiarity with the subject to decipher. Let me try to explain it

​

"The knuckle rap test reveals a very dead cabinet." The knuckle test is not a reliable test because it is a point excitation of a panel. In reality the well-distributed pressure within the cabinet does the excitation. I well remember a Japanese manufacturer showing me, while on a factory tour (before I joined Harman and became a competitor), that they poured about an inch of concrete into the top of every box so that customers would be impressed by the almost inevitable knuckle test .​

​

What matters is the sound radiated from panels, not movement of the panels - and this is measured in spinoramas. Some panel modes allow considerable movement, but the sound radiated from different portions cancel each other. So a knuckle test, or an accelerometer placed at one location cannot reveal what a panel will radiate. It is understanding this that allows good engineers to strategically place internal bracing to eliminate bothersome modes while not spending materials or mass addressing innocent ones. Enclosures do not need to be "inert", only acoustically "quiet". But when marketing gets into the act we get monster massive boxes whether they are needed or not. It is good for imaginations though.​

​

Not all panel resonances/vibrations radiate sound the same way. Some radiate effectively, some don't. If they are audible, they will show up in the spinorama (i.e. frequency response) measurements. Therefore, the full spinorama measurement is sufficient to detect audible cabinet resonances.

Adding mass and rigidity** is an effective but inefficient/inelegant way to prevent audible cabinet resonances. The problem with the knuckle test is that the person cannot differentiate between a poorly designed/constructed cabinet from one that is well engineered and optimized to be "audibly quiet" but not structurally "inert" (e.g. to minimize cost and weight). The knuckle test actually penalizes designs optimized based on understanding of advanced structural acoustics.

Note:** Being pedantic here. Stiff structures and rigid structures are not the same. Stiff means a high "spring constant", and therefore high natural frequencies. Rigid means it is hard to deform the structure. A drum only radiates sound well when the drum skin is tightened, i.e. stiff but not rigid.

 

[thewas]

Note:** Being pedantic here. Stiff structures and rigid structures are not the same. Stiff means a high "spring constant", and therefore high natural frequencies. Rigid means it is hard to deform the structure. A drum only radiates sound well when the drum skin is tightened, i.e. stiff but not rigid.

Sorry for being then also pedantic, but for mechanics only the term stiffness is used which shows how much something deforms with a given load (force, torque, shearing etc). Your above "stiff but not rigid" drum is just an example of something having a high stiffness in one direction and low one in the other (resulting also a low bending stiffness).

 

[Deleted member 46664]

The knuckle rap test has a couple of things in common with the square wave test:-

1. it is useful and informative, if you know enough about its relation to audibility during music playback
2. a ‘better’ result is often not related to audible superiority…so it is misused/overused by people who don’t ‘know enough’

IMO the ‘hand on speaker playing music’ test is less misleading than the knuckle rap, but still somewhat misleading, since one can probably feel vibrations that are audibly masked.

cheers

Yes you will feel vibrations that are audibly masked ...but only in the showroom.
But do you really want to wait until you get your precious new speakers home to find that out?

Both the knuckle and feely tests are extra information... we're eliminating the stinkers, not doing precise science.

 

[Mart68]

Maybe we read different rags, but I picked up the Stereophile habit round 86-87 IIRC. The message was McCantz and Sansewage were for tin eared cheapskates, and a budding audjophile should be shopping Luxman or in a pinch NAD while saving for entry level Audio Research or Conrad Johnson tube gear. Sam Tellig was the only one to recommend 3 figure products. With luck some of these even received a C on the recommended component list that one could purchase without shame, and a confessional with your local priest. Speaking of priests, these self proclaimed golden eared wonderkind and the whole process of monthly annointments is more than a bit reminiscent of a religion.

Timeline may vary with different magazines but by the time I started buying them (circa 1988) all the UK mags had moved over to subjective reviews in the main. A few still produced measurements as an adjunct or had some blind-testing, at least for loudspeakers, but the review format had changed from 90% of the review being measured performance and a discussion of that, to 90% listening without any controls and writing poetry based solely on it.

Currently reading through old issues of the American magazines and the sea-change broadly occurs between 1985 to 1990.

There's another change starting in the early 1990s when things like power cables, speaker cables, interconnects and fantasy devices like Shun Mook begin to get reviewed on a regular basis.

Given this was pre-internet ubiquity the magazines were the only source of information to the enthusiast or potential purchaser. You could alternatively ask your dealer but with few exceptions the dealers took to the new paradigm with glee. Customers who were previously satisfied with what they had now wanted to upgrade due to FOMO, plus they could now be sold accessories with high mark-ups and so far more profitable than just selling the boxes.

 

[NTK]

Sorry for being then also pedantic, but for mechanics only the term stiffness is used which shows how much something deforms with a given load (force, torque, shearing etc). Your above "stiff but not rigid" drum is just an example of something having a high stiffness in one direction and low one in the other (resulting also a low bending stiffness).

I learned the terminology from Professor Hambric.

https://www.researchgate.net/publication/243716469_Structural_Acoustics_Tutorial-Part_2_Sound-Structure_Interaction

 

[thewas]

I learned the terminology from Professor Hambric.

https://www.researchgate.net/publication/243716469_Structural_Acoustics_Tutorial-Part_2_Sound-Structure_Interaction

View attachment 202466

And your above quote exactly mentions only stiff(ness) like I wrote above and does not differenciate between stiff and rigid like you did.

 

[NTK]

And your above quote exactly mentions only stiff(ness) like I wrote above and does not differenciate between stiff and rigid like you did.

What term do you propose to describe a structure that is stiff and doesn't radiate sound well?

When you tighten the drum skin, the stiffness in the longitudinal direction does not change (assuming its linear elastic limit has not been exceeded), however the flexural stiffness is increased.

 

[Deleted member 46664]

What term do you propose to describe a structure that is stiff and doesn't radiate sound well?

Inert

 

[NTK]

Inert

Inert is the term that Dr. Toole used. I am attempting to find a term that is a bit more descriptive. A speaker enclosure made from 1 inch thick steel plate welded together with full penetration welds is inert, so is one made from rubber. One is rigid, the other is not.

 

[thewas]

What term do you propose to describe a structure that is stiff and doesn't radiate sound well?

When you tighten the drum skin, the stiffness in the longitudinal direction does not change (assuming its linear elastic limit has not been exceeded), however the flexural stiffness is increased.

The bending stiffness remains very low compared to the other directions, so it is not fully stiff from mechanics definition. By the way you could have a mesh/matrix with high stiffness in all directions and it would be able to transmit the airborne sound through it, so its better describing the individual case in necessary detail instead of trying to create some ambiguous own definitions/abbreviations.

 

[Deleted member 46664]

Inert is the term that Dr. Toole used. I am attempting to find a term that is a bit more descriptive. A speaker enclosure made from 1 inch thick steel plate welded together with full penetration welds is inert, so is one made from rubber. One is rigid, the other is not.

Private terminology amounts to obfuscation which inevitably leads to confusion which can quickly lead to objection.

On a forum like this the more "plain english" you are the better.

 

[DesEsseintes]

Back in the day, I used to love talking to properly expert and qualified designers, as they usually seemed able to explain concepts in plain English so I/we could understand and absorb the information passed to me/us. It was the second rate 'designers' that fudged and fumbled, trying to make things sound so incredibly complicated to what I now feel disguise their basic ignorance and the UK market back then, as well as the US market right now apparently, was and is full of 'em!

Such a great shame that many of the luminaries Erin has interviewed are now retired or about to be so. People like Mr Fincham though, were usually too busy to entertain the dealers his products were sold by, but there were plenty of others back in the day. I wonder if this industry still attracts genuinely talented engineers or is it such a niche now that they go into other fields of electroacoustics?

I work in a different field of engineering, but your statement about being able to explain things simply rings true. Currently managing a team of design engineers, an cutting through any BS is a must. Do it early, and do it often. Thankfully not a problem I have to deal with too often.