There is certainly a lot of air moving in this thread for sure......
Talk but not walk?
Hi Guys
This isn't meant to start a fight, but it is important to on lookers. As a qualifier, I have my own audio forum where we report on audio issues as we empirically test them. It helps us short cut on theories and developing methods of listening. We have a wide range of systems and they are all over the world adding their experiences to the mix. Some are engineers, some are artist and others are audiophiles both new and old. One question I am almost always asked while I am visiting other forums, from some of my members and also members of the forum I am visiting is, why do so many HEA hobbyist talk theory without any, or very limited, empirical testing or experience?
I have been around empirical testing labs since I was a kid, and one thing that is certain is, you can always tell if someone is talking without walking. Right now on this forum there are easily 20 threads going on where folks are talking theory and there is absolutely no doubt to any of us who have actually done the testing needed, that the guy talking has never done the actual empirical testing themselves. I've seen this happen with HEA reviewers and designers and a ton of hobbyist. My question is this, why?
You would think that this hobby would be about listening and experience, so why are there so many myths created and why, in this hobby in particular, do people claim they know something without ever experimenting or being part of a team of empirical science folks. It's not that hard to setup a real empirical testing ground, so why don't we see this happen?
I'm not asking for peoples credentials, and I'm not asking to be trolled, I'm simply asking why talk and not walk? In many ways HEA is on pause while the rest of audio innovation is moving forward. I'm also not asking you guys to defend HEA, we've all heard it been there done it. What I'm asking is a very simple question in a hobby that is suppose to be based on "doing", why fake it?
thanks, be polite
Michael Green
www.michaelgreenaudio.net
2,164 responses Add your response
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testpilot 182 posts 05-15-2018 9:30am The sound gets refracted ("back" removed) towards the listener due to the change in the transmission medium i.e. hot and cold air >>>>>I want to get on board your explanation. I really do. Can you be a little more specific and go into detail just a bit? So far I’m thinking hmmmm, maybe partial credit. It’s based on the same principle as why can we hear sound for longer distances in winter than in summer. You have already given the theory as to the why and how in the post above. >>>>Not exactly. You’re close. Very close. The analogy is why we hear better from across a lake on a cold morning rather than later in the day. It’s because the temperature of air higher up above the lake is warmer than the air closer to the lake surface. And sound travels faster in warm air. Thus, sound waves higher above the lake surface up fall over the slower sound waves lower down and bend down toward the listener. So he hears better than if there were no temperature gradients. There would be no temperature gradients in winter or in summer generally speaking. Except fir the case I gave of a cold morning and warm afternoon. The temperature of air near cold lake water slows the speed of sound. In the afternoon the temperatures above and near the lake surface are more equal. |
I've been tuning for many years, so maybe it would be helpful to some of the people reading this if I talked a little about my own experience. Like most everyone else, I got started with tuning because I was looking for better sound. I felt that what I had was ok, but I wanted more. I began with acoustical treatments and then moved into stripping down components, using minimalist wires, and tweaking the electricity. At this point in time, I really can't NOT tune a system. How do you listen to a component with its chassis top on when you know that removing it will give you a sound that is so much more dynamic and open? How long can you look at a capacitor strapped down with a plastic zip tie, when you know that freeing it will give you a three dimensional, holographic soundstage? If it's me, the answer is - not long at all. :) As my systems became more finely tuned over the years, I began to notice that recordings I remembered as all sounding reasonably good differentiated into a large group of recordings that sounded spectacularly good, and a small group that didn't sound anywhere near as good. What I also observed was that if I put together two equally good sounding systems from different components, the same recording could sound wonderful on one system and ho-hum on the other. It wasn't the recording. At this point, I could have done one of three things: One, dial the system back until all recordings sound just ok. Two, live with the tuned in system that does most recordings extremely well and ignore the recordings that aren't so great. Or three, tune the system to the recording. I'd like to say that I've been in camp number three all along, but that isn't true. Opening a system up by stripping down components, using good platforms and good wire, careful setup of speakers and room treatments, and releasing tension from the electrical will get you to spectacularly good sound. But tuning to the recording is really a different skillset. It's the same tools and techniques, but you need to understand what sonic effect each move has and then put together the right combination to get yourself where you want to go. With so many variables involved, it was really more than I felt I could do. What changed things for me was the discovery of the Audolici A25M. The Audolici is an integrated EL34 tube amp that makes about 30W per channel. It's a lovely sounding amplifier even untuned, but what really sets it apart is its ability to be tuned to the recording with wooden blocks under its chassis. What this means is that recordings that had sounded distant, unfocused and uninvolving can be tweaked into sounding beautiful in just a few minutes. And the spectacular recordings sound just as spectacular as ever, with their own settings. Essentially, what had been a complex process involving many different parts is now reduced to an adjustment on a single component. In practice, I find I don't actually need to retune for every CD I put on. Many recordings will sound at least good to very good with the same block setting under the amp. But when I put on something that has a distinctly different recorded 'key', I'll know it inside of 10 seconds, and I adjust the blocks until I get the sound I know was in there. :) I know there will be people who read this and have no interest in going down this road. Believe me, there's no judgement. Every person needs to decide for themselves what great sound is, and how far they're willing to go to get it. I'm just telling you about what has worked for me. |
I said it before and I’ll say it again. What type of wave is a sound wave? In this case, the particles of the medium move parallel to the direction that the pulse moves. This type of wave is a longitudinal wave. Longitudinal waves are always characterized by particle motion being parallel to wave motion. A sound wave traveling through air is a classic example of a longitudinal wave. Hel-loo! |
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bill333 How do you listen to a component with its chassis top on when you know that removing it will give you a sound that is so much more dynamic and open? How long can you look at a capacitor strapped down with a plastic zip tie, when you know that freeing it will give you a three dimensional, holographic soundstage? If it’s me, the answer is - not long at all. :) So taking off the top of a component will "free" it dynamically etc, and releasing a capacitor releases the soundstage to bloom into 3D? This sounds like something along the lines of folk homeopathic ideas such as "like cures like." That is, concepts that draw some mildly appealing relationship in the mind of the user, but without any actual scientific grounding in reality. Unless of course I’m missing something. bill333 can you give us a non-mystical, technical explanation for how removing the chassis top of a component would cause those audible differences (or releasing of the capacitor)? (BTW, I’ve had the top off some of my equipment before - pre-amps etc - for different reasons and...no...it did not change the sound). |
WaveMotion Motion of the water is different than the motion of the wave. Water at each location moves in a circular path, but the motions at different locations are “out of phase”, which means that when water at the left of the diagram is moving to the right, water a quarter of a wavelength to the right is moving down, and water next to it is moving to the left, and next to it is moving up, etc. The overall effect is a an “apparent” wave moving to the right. Thus, the velocity (speed) of a wave is not at all the same as the velocity of the water. The horizontal movement of the water when a wave passes is approximately equal to the up and down movement of the water. If you are on flat water and are parallel to waves made by a passing boat, your boat will move side-to-side as much as up-and–down as the wave passes under you. The side-to-side movement actually creates most of the difficulty in balancing the boat in such a situation. However, under typical conditions in the bay there can be such varied wave action that you can’t easily distinguish horizontal and vertical motion. Case closed. |
I also want to know more about “freeing” the capacitor? You can’t mean allowing it to vibrate freely? Next to other caps and parts that are loose and perhaps leading to a short? I find well damped caps sound better, not worse? I get the wood blocks under gear. I get the room treatments, but they will never be allowed in my living room nor many others here. So take the cover off? Yes, I have found my old tube preamp sounded better that way. It depends on the component and not universal. |
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geoffkait, My mentioning of me talking the talk, as practically worthless as it was, and saying that whoever would do what I imagined while not having anything better to do would be the person walking the walk meant just that. The one who fills the room with some significant Helium content and then listens to her/his equipment to investigate if there is any difference in sound would really be The Walker, empirical to the core. I have no idea what would happen but would not mind hearing someone else's experience. However, much more than hearing about that experience, I would like to meet the person and ask "Why? Why on Earth did you fill the room with Helium?" So, for that small unimportant non-experiment purpose, I am not aware that either you, or Michael Green were walkers. Good news is, he never even put one word about it, either, so he is not faking it like you and I (according to initial premise of this thread). shadorne, I am sorry for confusion, and I agree that Reynolds number is quite an silly input here, but it all started with the statement that a piece of equipment organizes laminar flow by being placed in its path. That, reminded me of Reynolds number which then reminded me of how I use changes of it in what I do when I am not here. That brought me to Helium and, subsequently, to an imaginary room and what would happen in it soundwise. That room (medium inside of it) would have different Reynolds number than a regular air-filled room so that was my shorthand for "room with changed air composition", I guess. I had no conclusion nor do I still know what "organizing" laminar flow (implied: already existing laminar flow) really means. |
Hi Bill333 Very nice post! This goes all the way back to recording studio amplifiers. When the amps came off the trucks from shipping we would go through them and remove the shipping ties before we would mount them. It was one of the differences between amps we took on tour and amps used in the studio. Same is true with home audio amps and other components. The walk here is the fact that caps and the other parts (including cables) weren’t designed and spec-ed out with tie wraps around them. Glue, tie wraps, shipping bolts, chassis and other common parts are not part of the parts manufacturers design. Audio parts are very specifically designed to meet spec and when you add materials (such as a tie or glue) you are of course changing the performance. I am sure some can’t hear the deference, but I have not met many of them. There is the problem of "over build" in component designing that is getting noticed more and more and causes many listeners to go with a designers basic models instead of flagship models. When you have too many parts too close together the parts are not able to perform at their spec. This actually causes blockage of the audio signal and makes the soundstage start to collapse or get congested sounding. I personally prefer listening to low mass components or at least ones that respond well to vibratory tuning. The Audolici A25M is an excellent example of a well laid out component. Still not light, Valeriy strategically spaced out his parts nicely. Other designers have also created works of simplicity as an art. I do not keep my chassis on any of my components. I don’t like that closed in sound. Plus if I want to do some tuning the last thing I want are plastic ties squeezing my parts. I want to use products at their point of spec design. Meaning I want to use their leads, stems and seals as close to factory design as possible. Very good posting Bill333 Michael Green www.michaelgreenaudio.net for a reference the 40 foot system, designed by us in Nashville |
The tube amp referred to is not point to point wired and all the components are certainly affixed pretty darn tightly to those boards. I much prefer point to point wired tube amps sonically. I looked at internal pics. If one does not glue, or bolt, or clamp a part it is not only vibrating with the music it is potentially dangerous in a high voltage amplifier. The best sounding capacitors are made highly damped such as the Duelund CAST caps. How these realities all work together is most interesting. Removing crossover parts from the bombastic bass cavity of a speaker and placing them outboard does improve the sound. This I have also walked the talk on with experience. Why do they sound better outside the speaker cavity? Two main reasons. You correctly state one now has the room to properly space all the parts - particularly inductors. Also, the parts are no longer vibrating, but are now isolated from the cabinet. |
michaelgreen, The walk here is the fact that caps and the other parts (including cables) weren’t designed and spec-ed out with tie wraps around them. Have you ever considered that this is because tie wraps are irrelevant to the performance of caps? Computer circuit boards/drives etc are spec’d for a certain performance, and yet they can be put in any number of different casings, and affixed any number of ways, and the performance will be the same. (You could of course mount them in a way so poorly that connections break or over-heating occurs to failure, but there is a wide spectrum of installation possibilities none of which alter the performance of these items). If you claim that tie wraps actually change the performance of a cap, what is your actual technical explanation and what is your evidence? Can you show us measurements before and after a tie wrap has been removed? And given you have thrown around the word "empirical" and "scientific" in your op, can you tell us the steps you have taken to control variables in your evaluations of these effects - obvious variables such as human bias and error? You recognize these concerns to be an important part of being a good, careful empiricist, I hope? Audio parts are very specifically designed to meet spec and when you add materials (such as a tie or glue) you are of course changing the performance. That’s an assertion without evidence, and it doesn’t follow at all. In industry, ties, glues and all sorts of other parts of a device are used that do not change the performance - if they did, they wouldn’t be used, or the device would be designed with interaction of all the parts taken in to account. (That is, in good design - one can always find examples of bad design - but not everything is badly designed, of course). I’ve used ties, glue and solder to, for instance, fix or adjust wires in various devices I own (both AV and audio equipment) and it has never changed the performance in any noticeable way (nor is there any reason to have expected any change, so long as I wasn't doing something stupid like running fine signal lines in close parallel with power lines, etc). In fact, I completely re-arranged all my cabling, with all sorts of different ties, plastic, metal, etc. Did this change the audio performance of my system? No. Not one bit.
Again - I see no actual technical explanation you’ve given in support of that claim. Instead it seems, as I mentioned to bill333, a type of folksy association - "congested electronic parts yield congested sound." If you are really the empiricist you claim, surely you understand how your explanations are wanting. Michael, you were the one who made a big deal of testing, empiricism, and science. I’m just wondering if you are actually "walking the walk" in terms of being a careful empiricist. |
Michael Green, Why wouldn't an, for example, amplifier work to manufacturer's specification once received straight from the factory? Ties, rods, rings, whatever else, in place as manufacturer left it. I am not talking about some packaging material, but about a finished product taken out of the box? Why shouldn't we expect that manufacturer, when tweaking and finalizing before releasing to the market, is testing the product as customers would use it? In fact, why would not manufacturer do it? I have a hard time believing that someone engineers a half-baked product and never pays attention to how it sounds when finished? I am sure it is possible, but why would anyone put time and effort into engineering something that she/he would not adjust as the finalized product? Regardless of personal opinion what does or does not sound "better" (tied or untied, etc.). Or, did I completely misunderstand your post, which is also very likely? If it is only about removing vs. not removing shipping material (as it seems is the case in your example), why would anyone not remove it? Even if you forget the sound, which may or may not be different to someone's liking, the machine would not look the same as what you envisioned when parting with money. When you have too many parts too close together the parts are not able to perform at their spec. This actually causes blockage of the audio signal and makes the soundstage start to collapse or get congested sounding. This is an interesting one. It seems that when parts inside some equipment get congested (capacitors etc. closer together), the virtual image of the performance, as heard from your listening position, also gets congested (musicians closer together). Serendipity at work? It would be interesting to know why would that happen just like that. I do not doubt many things (including this) can happen and that is why there are good audio equipment engineers out there who think of all the details, but this one is, kind of, funny. Almost makes me think that, if amplifier is turned to one of its sides, I should expect to hear a cellist sitting on top of a violinist. |
glupson, Nice to see people like yourself bringing critical thinking to MG’s claims. They apparently don’t allow too much critical thinking on Michael’s forum. Skeptical challenges to their ideas - simple things like asking for measured results for some of the more controversial claims, listening tests constructed to control for the variables of people’s imagination etc - are frowned upon as "bad vibes" and a sign one is not being sufficiently open minded. (You’ll find exactly this attitude on any number of fringe medicine, New Age, psychic medium, astrology, etc groups...funny enough). There isn’t the luxury of of fan-worship and lack of skepticism when he brings his claims here. (Though I’d like to be wrong insofar as he could actually substantiate some of his claims). So I’m sure it’s not as comfortable for those claims to be brought here. But then: A wise university professor pointed out: Discomfort is a sign that something that you think is right, is being challenged. And that should be exactly what you want, because that’s exactly when you are most likely to be on the cusp you are learning either that you are wrong - or by taking on the challenge you gain more confidence you are right. One can either take that opportunity to be challenged and learn from it, or use the discomfort to declare those who challenge your claims as "trolls" as a way of running from the challenges. As for how the crowding of the electronic parts producing crowding of the soundstage, you’ll find quite a bit of these folksy-level "explanations" in MGs stuff. For instance he’s written how running wires close together would produce a "tighter" sound, a bit more apart will yield a bit more open sound, moving further apart yielding even more open sound. As I said, it’s something of a piece of the folk-wisdom behind homeopathy - the same conceptual appeal of "like cures like" (even though there is no actual basis for the claims made on this hypothesizing). |
Hi glupson I don't want to answer for HEA companies, but I will say, that when listeners start to tune their views change quite a bit toward manufacturers. I also know for a fact that many guys and gals who start tuning sell off their massive components and get products that tune easier. Michael Green www.michaelgreenaudio.net |
prof, Thank you for your compliments, but I do not think I deserve them. I do not even think I am using any kind of critical thinking here (this forum), if I even ever do it anywhere except at work. I am approaching these things with some lightness and open mind. Still, I do notice and then ask. I try to stay neutral which means that I keep my mind open that there may be something to whatever someone is claiming. That is why I ask these questions, to clarify what seems odd to me at first reading or to add what I think is the answer to what someone was asking about in some conversation. Enough about me as me. When it comes to tweaks, lovers of tweaks fiercely defend them and seem to dismiss anyone who is not a follower. Too much time, too much cost, too much uncertainty, too much emotions (at least around here), simply not worth it for some. Some people dedicate their free time and disposable income to tuning/tweaking/perfecting their system (room included) to match the ideal they hold dear. Some cannot care less and intermittently pick and choose what to focus on. I would be a hard sell for tunable cable elevators, or demagnetizers for a piece of plastic injected with non-magnetic material, but if someone likes them and thinks they are worth it, even as a placebo, so be it. It is good for them and it sounds suspicious to me. I would like to know their explanations and maybe become a convert, but that is about it. Sadly, more often than not, any discussion ends up in Internet hostilities and observers, such as I, do not get enough "data" to make our own opinion. However, I do have to admit that about 25 years ago, a friend of mine and I borrowed Cardas speaker jumpers (those little things connecting inputs on biwireable speakers, a couple of centimeters long), that were costing way more than we could have ever dare to spend, from the local store. Neither was our amplifier anything special (so-called mid-fi at best), nor were the speakers anything great. We tried it for fun as, for all we knew, we could have connected those inputs with metal buttons and it would have been the same. Well, the difference was audible to both of us. We were sure it would not be, but it was. Repeatedly. Another day, same result. I have no idea why it was, even if it was just a bias of some sort, but we heard the difference. Having said that, I have no plans to ever buy "upgraded" speaker jumpers but remember those anyway. I am more of a talker (am I a faker once I admit I am a talker or I become genuine walker in the field of talking?), but appreciate those who try and tell me how it was. I appreciate even more if they explain why it was. Of course, financial disclosures are sometimes needed, but rarely seen in these woods. |
Gurus also like baby back ribs, so I'll see you guys either later on tonight or tomorrow. Prof, we should also talk about your hard on for me. Shouldn't you just ask me out. I mean I can check with my girlfriend, or maybe the three of us can catch a movie. Seriously though I have a question for you, are you really May Belt cause you sure sound like her in your writing? Seriously you sound just like her. Your like one of those "no answer can be the right one kind of internet troll". I'm flattered but honestly I like women. That shouldn't stop you from getting a picture of me to hang on your mirror, but just so you know we can never have anything meaningful long term. Michael Green www.michaelgreenaudio.net PS: Prof Fridays no good for me maybe Saturday :) |
So name calling is all you have, Michael? And you think this is a good look for you? Your refusal to answer challenging questions is ever more conspicuous. You can toss all the "troll" accusations you want - as is your modus operandi - but what you can’t do is justify them. You can’t point to anything in my first reply to you that isn’t reasonable or pertinent, all the way to the questions and points in my recent reply. That’s why you aren’t answering them - and anyone here can see the pertinence of my questions and comments on your claims. I even took up an idea in your OP, about the nature of empirically based evaluations, and explored the roll of empirical claims, in a way you just ignored. In contrast your replies to me have been evasive and bereft of argument or substantiation of anything you wrote, often comprising passive-aggressive disses, and finally in this last post...you fall to pure trolling. (See, I can justify that description because your post actually fits: The method of a troll is to ignore the arguments made against his position and respond instead with baiting insults - precisely what you just did). So your hypocrisy could not be more vividly on display. And all the more so because your bluff has been called; when you are asked if you are in fact walking the walk of employing good empirical methods, you evade, evade. BTW, no date for you. I don’t date anyone Geoffkait has dated, and your torrid affairs on other forums are legion. ;-) |
prof, As much as I feel that many of the "improvements" floated around in audio community are not worth much, if at all, I am aware that no technical explanation for something does not necessarily mean that said something does not exist. That has happened throughout the history and is, I think, the culprit for development of what we these days call science. As science progresses, more answers become available and what used to be magic then becomes a well-understood knowledge now. Who knows, maybe we will all be feeding capacitors with organic gluten-free electricity one day to make them happier after someone discovers a CHF-inhibitor (capacitor happiness factor-inhibitor) in electricity produced close to wheat fields. I cannot agree more that just claiming something and trying to get points for it without more structured challenge to own's observation is pretty useless and reeks of lack of credibility (Like my Cardas jumpers, although we tried a few times on different days to exclude too fast of a conclusion. The study was aborted because there was a much more interesting party in progress nearby and we never regretted it.). I know that Michael Green did not elaborate on this crowded capacitors and musicians thought, but I put him in a very similar category as that friend with Cardas jumpers and myself. Probably noticed something, believed in it, and possibly not really thought too long and too deep about why that is. For one reason, or another, I did not expect overly elaborate answer. With all due respect to Michael Green, just a glance on his website made me think he is not a seasoned electronical engineer, but is pursuing different avenues in this hobby/business. I may be wrong on that one and I apologize if it is an unacceptable assumption, but that is how I saw it. If I wanted to get deep to the core of this crowding business, I would go straight to Accuphase engineers (or pick any other heavy-duty manufacturer) and ask about it. However, as Michael Green mentioned it, I thought it was worth dropping a word here, too. I never know what someone may know. The statement about listeners getting biased towards manufacturer seems simplified, but quite plausible, though. As I write this, I started thinking that problem with these tuning/tweaking supporters and those against them may be in tuning/tweaking crowd trying too hard to gain credibility and then using words and statements based somewhere in current science, but not having it all baked well-enough together. That way, anyone with a minor knowledge of physics or whatever matter is discussed, can reasonably start running laps around them. Now, as Michael Green is some sort of a host in this thread, or at least the lightning rod, I could use him as an example. I have no doubt that his room-manipulations change how the room sounds (sound in the room) and that it is often, if not always, for better. Anyone who has ever entered a cave and a family living room would have to agree that they sound different. In theory, placing a toothpick in a room will change a sound in there, refraction, absorption, change in volume, whatever. He, from what pictures show, places very big toothpicks, so to say. Of course it will change the sound. Now, if you take a bunch of big toothpicks and have enough time for trial and error set-up process, you may get great results. Eventually, you will place them where they work the best for you and that room. If you go all the way, you can experiment with toothpicks made of different wood, too. That is all easy, provided enough time and resources. However, then you want to convince the world how great it is and you start talking after walking. You start using serious words to give legitimacy to your findings and even construct a theory or two why it is so good. That is like throwing a whole bunch of banana peels in front of you. You believe in what you say, and to many it seems quite right, but then there is a guy you did not see coming. He is on the other side of your screen, you have no idea where he really sits and how he looks like, but he reads your posts carefully. And he has PhD about laminar flow and has been dealing with intricacies of the flow for decades. Of course, he could annihilate you on that topic, he'd better be able, but he may not be interested. And then, there is an engineer fully dedicated to capacitors and he is a jerk. And the obnoxious professor who sits on IRB of a major teaching institution demanding structured answers. And on and on and on. In the end, it would have been better if you toned it down from the start than exposing your weaknesses. Who knows, maybe those demagnetizers work. I personally doubt it. |
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Hi glupson OK, Laminar flow, effect or line. You & Geoff were on target for the name even though my use of the words had to be bent some as I looked at what to call the energy there. If you look on TuneLand you can see the drawings and more description but for the short version here laminar effect works like this. When a source produces the oscillatory motion in a room it stimulates the already established patterns of pressure. Meaning the info contained in the new motion may be different but the pattern has been in play since the enclosure (room, house, dissipative mingle) was built. Part of these mechanics is the room's walls, ceiling and floor. Your room is electronically charged by the Earth's fields. It's actually a continuum capacitor, not only because it is enclosed but also because most homes have electrical wiring surrounding the internal structure. Geoff talks about "time of day" listening. This is a very real event that never stops. Not only does the cycle have certain shifts but also seasonal shifts change the Earth's fundamental interactions inside of every room. Your not hearing things, or should I say you are hearing things. Your hearing things and your feeling things all the time and even though you might think your standing or sitting still watch what happens when you have an inner ear infection, you loose your balance. That's all part of the power your system has. To listen to your particular laminar effect in your room is simple. Pick a wall with not much on it. If you start talking aloud in the center of the room and move toward that wall, when you get about 8" or so from the wall you will hear a sort of splashing sound that travels along the wall heading toward the intersections (seams) of the room. Back away and move forward a few times and you can pin point where the on coming sound pressure engages with the pressure coming back off the wall. This is called the laminar line. From the laminar line to the wall itself is called the laminar flow. Every suface in your room that is able to produce a reflection has a laminar effect. As I said earlier it's a continuum. You don't turn it on or off it's always there. Walk inside of your house and listen to the different sounds of each of your rooms. They all sound different. That's because the materials and their structure (LxWxH) are all different. There's more but I usually break things down to 4 variables, size, material, gravity and charge. How much does the laminar effect play in this? Get 2 friends of yours and try this free experiment. Cut 2 pieces of cardboard out 5"x24". Place your ear about 5" from that wall we were listening to. Have your friends from either side approach you with the cardboards edge touching the wall (the cardboard will be out from the wall about 5"). If you look on TuneLand you will see this. As they approach you from either side you will hear the Laminar zone shrink and as they get right up to you it will sound like the rest of the room has somewhat disappeared. Have them move in the other direction and you will hear the zone open up again. Once you start playing with this you can make your own Sound Shutters out of cardboard or hobby wood and you will be shocked by the control you will gain over your walls. Michael Green www.michaelgreenaudio.net |
All this makes interesting, if not debatable reading. I have been to what is one of the acoustically greatest stages in the world, the Sydney Opera House. The magic that happens there is truly a wonder of the world. If I could get my music room to sound 10% of that I would be a happy man. If I could afford I could a worthy stereo, I'd be happy. I read recently about the work Franck Tchang did with his static resonators with different metallic properties. Fascinating. Then there is the SOH with its phenomenal acoustic properties. I haven't travelled to the majestic concert hall of the world, but I will freely admit that acoustics can be changed using all sorts of materials and placement. I would not think there is one spot where a stereo system is perfect in placement in a room. What does change though is the listeners perception of change. I can sit in one chair or another in my lounge and the same LP will sound perceptively different, or the hearing in my ears are way different. Probably the way the breeze passes from one and out the other... :) |
The Tunable Speakers I’ve been making speakers a long time like many of you. Early on in my adventures I noticed a problem. Everytime I walked into a different recording studio the same speakers sounded different and I ended up spending all kinds of time playing with the EQ to try to find a reference point between the "Live Room" and the "Control Room" and than there was the playback or "Mastering Room". Guys would take the recordings and play them in their cars, and some used headphones and some just decided to suffer through the control room monitors. You’ve all seen pictures of the recording console with several different pairs of speakers. Many times JBL, NS10’s and one or two others on stand by. In the late 70’s I finally got tired of having to deal with this when I was doing the setups, and I started playing with the idea of making a speaker that I could use with some kind of consistency. For years I would build custom speaker stands and speakers and speaker clamps until I finally landed on something that worked for me. The first tunable speakers were crude torture looking things, but they worked and studios started using them for main mix down monitors the "studio 5". Time went on and I was asked to be the acoustician for UMI (United Musical Instruments). This opened up the door to work more closely with the actual making of horns, wood winds, cellos, guitar, violins, violas and the coolest of cool, building rooms for Steinways. Around 1989 or so I started to make my speakers out of instrument woods instead of MDF and found tons more tone to play with. This put into action the next 15 plus years in design hunting for the right drivers and parts and pieces so that I could make the most simple to drive speaker that I could (and low mass). For tweeters I used ribbons, silk domes, horns and pretty much the full range of everything I could find. Every time I went more complicated I ended up needing crossover work done and my goal was to go crossoverless. I had found the sound of the cap I wanted to use but drivers were a bugger. Finally I threw out everything and started from scratch. On the cabinet side I was doing pretty well as I got the inside tuning bar down to a science. The Tuning bar works like this. Instead of building heavy cabinets the tuning bar applies the force from the inside and the tuning bolt and washer on the outside supplies the inward force. Because the cabinet has both inside and outside force going on you can adjust the cabinets tone. Where most cabinet designs push outward mine equalize the pressure. The wood of the speaker is low mass compressed board treated with instrument finish. Except for the front baffle board which is a guitar body board. The whole speaker is then veneered in cherry. The drivers however were a pain. I didn’t like anything I heard. There use to be some nice stamped drivers made in Europe but lately nothing that was what I wanted. I decided on modifying the standard Vifa D27 or ScanSpeak but still I wasn’t happy. Then it dawned on me to make my own baskets. This changed everything. I saw Kosst said I used 3.5" paper tweeters (stamped) as if that was a bad thing lol. Well it would be a bad thing except my baskets are redwood. Again the "walk" Kosst. All my drivers are redwood voiced drivers. The tone is out of this world. Ask the folks who have them. They’re pretty darn snappy pappy:) The tuning is just as cool as the speaker. Lets say I’m playing cymbals and they are a little loose sounding. Lets say the halos are a tad too wooly. All you do is barely tighten the Tuning Bolt and the cymbal will tighten right up. The new Revs are pretty special. And yes if someone wants the ribbon or silks we do custom sets. We’re doing a set of ribbons right now. Michael Green www.michaelgreenaudio.net |
I can see some confusion that many people are facing concerning words like laminar flow or pressure zones. Well not to worry even initially I too had a though time trying to wrap my head around it. How would one define the meaning on laminar flow or pressure zones? Where are all these found in a given space or room? What is the first step should I do in order to have an understanding on them? Well these were all the questions that I was asking to myself again and again. After years of practicing hopefully i could shed some light to those who are still not clear on them. It has got to do with pressure build up by your room itself. For an example if you walk out from a room to an open space your voice will sound open, less focussed and the loudness will be lesser as in comparison when you are in an enclosed space. This is a simple example on what a pressure in a room is causing towords our speakers when they are singing away and activiating or loading a given room. Of course speaker to room size ratio and thier placement is important as that will also determine how much of pressure zones will it activate in a room. Now what we are tuning here are these pressure zones. To give them a much more effective and organized way to work with our speaker and room itself. Pressure zones will be more towards acoustical space within the room itself and laminar flow are the pressure build up around the corners travelling along the walls of the room. I tune them by using my voice which i hear and feel the resonance within me. Hearing a change of tone and openness in my voice dictates if the flow is moving away or concentrated in that one particular area. Now I'm not here to argue or prove myself at all. Bringing in physics and other methodological manner is not what im interested as what im doing is more than enough for me to understand and make it work for me. But what I would love to hear from others here is to give it a try by voicing yourself in your room and listen for the changes this itself should give you some idea on what is tuning all about. Now from what Michael has mentioned above concerning those simple cardboard excersises was exactly what I did a few years back which brought out a whole different way of thinking and mind set to me in this hobby. Now onto what Bill has mention concerning on addressing mechanical and eletrical side this is another level of tuning that is equally important. I have removed most of my cable ties in my equipments that I can get my hands on and to be honest I was shocked with the improvments heard and it was a big improvment. As I said I came in with an open mind to what Michael has to offer and was very happy with the results. What got me thinking was how much of improvments I got just from listening to Michaels advise which was tottaly free. Of course knowing that he has such great depth of knowledge eventually gained my trust and of course I looked onto his products to augment my system more. |
prof said "Have you ever considered that this is because tie wraps are irrelevant to the performance of caps?" prof, why would I use a part without researching it? Prof, it’s my job to not only consider but to test. Also many of the producers of these types of products are happy to exchange info, like folks doing field testing for them. Can I ask you a simple question so we can see if we can get on the same page somewhat? How would you describe the difference in sound between the Vishay 1813 (yellow) and the ERO 1822? 3.3 of course. |
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Someone just mentioned Franck Tchang’s Acoustic Resonators. I mentioned them the other day while discussing mapping the 3D space of the room for sound pressure levels in connection with a number of room acoustics solutions. Since we are discussing pressure zones, sound pressure and air it might be worthwhile to take a gander at what the Stereo Times article says about the Acoustic Resonators. I am posting excerpts from the Stereo Times article below. The entire article can be found at, http://www.6moons.com/audioreviews/francktchang/resonators.html Franck Tchang Acoustic Resonators (review at Stereo Times), excerpts “The resonators also become focal points for intense overtone radiation. That is denser at their points of origin than in the surrounding air. As directional organs, our ears key into these radiation sources and our acoustic perception of the space we’re in is altered. Again, no music needs to be played to sense this spatial overlay. Speech will do, or the sound of our own foot fall. Being completely passive, the resonators can only be activated by received energy. As HF modulators, a full-range input obviously isn’t needed. Franck Tchang has used a spectrum analyzer to corroborate this action up to 3GHz. By affecting the ordinary acoustic damping through adding parallel values from the resonators, original HF content reappears. It becomes audible again and rebalanced against the LF energies. Treble decays improve and the subjective impression of audible space deepens. The resonators equalize air pressure differentials and can be installed in a fridge, mailbox or outside a room. Distance will not affect their efficaciousness. That’s quite a fatal blow to common sense but there it is according to the maestro. Franck has treated recording studios, performance venues, bars, living spaces and entire buildings. His demand as an expert tuning maestro is growing. That brings to mind Combak Corp.’s Kiuchi-San who enjoys a similar reputation in Japan. The moment you think air exchange where an entire building is submerged in, permeated and surrounded by air (except under the foundation of course), the picture begins to focus. That’s how these resonators defy distance. They’re equalizing the ocean of air that surround us, rechanneling certain turbulences, sync’ing up patterns. If you’ve got a massive geometry-induced pressure zone outside your house for example -- an area where gusty winds get trapped to apply structural pressure -- relieving this pressure must have an audible effect inside. It’s all connected. The mind cracker is simply the clash of scale. Big pressure, tiny devices. LF issues, HF solution. That’s where the mind hangs up. We’ve become conditioned to equate acoustic treatments with <300Hz attacks. That means bass traps. It means huge Helmholz resonators as notch filters. It means giant absorbers and diffusors. Time and again we’ve been told that low frequencies require large devices to counteract. That’s why Rives developed an elaborate in-ceiling address. The ceiling tends to be the biggest blank surface in a room. If high enough, you can hang in a faux ceiling and hide your monster traps in-between. Think about it. If you sound proof a room by sealing it shut, you increase its internal air pressures the moment music starts. You’re effectively making the room smaller than it was before. That compounds the issue. It’s out of phase with Franck’s views. His isn’t a brute force approach. It isn’t about dominating and straight-jacketing nature. It’s about helping acoustical energies flow again. It’s about dissipating clusters so that like water which always finds its own level, air pressures level out and equalize. This is a franck response: "I view my room as a bass guitar body, the resonators like strings and the air movement as the player’s hand." According to him and how far I can follow thus far, excess LF energy gets converted to HF radiation by making his resonators work. Work means getting them to oscillate. These devices are passive. They’re not perpetuum mobiles. To keep ringing, the resonators must continue to consume acoustical energy in their environment. However, they’re not drains. Energy isn’t killed by absorption or damping (actually, heat conversion to be technically correct). Acoustic System simply upsamples energy from lower to higher octaves. Bass energy enters the resonators. They oscillate. The resonator in turn puts out harmonics. LF goes in, HF comes out. That seems terribly oversimplified of course. Doubters will point at the fixed resonant frequency of the tiny oscillator and wonder how things add up.“ |
costco-emoji wrote, “And just like good ole’ Roger, it looks like Mike is loosing his cool under scrutiny and resorting to sophomoric insults and attacks. It’s rather pathetic.” >>>Whoa! Hey, didn’t he get the memo? I was under the distinct impression you are supposed to be the only one who’s permitted to resort to sophomoric insults and attacks. What’s up with that? |
Hi Kosst I'm sorry, were you talking about these speakers? https://www.michaelgreenaudio.net/tunable-speakers So I'm listening to Michael Franks "The Art Of Tea" what are you playing? Since you asked about my speakers I'm playing the Rev6 Signatures & Rev SW-15 Combo. And by golly they do sound pretty smooth around 6KHz. You know how I can tell? Because the splashing of the cymbals have that immediate attack but then there's that ultra smooth cymbal float that covers the room. I'd be happy to describe the soundstage to you. Michael Green www.michaelgreenaudio.net |
Speaking of vibrating capacitors and chassis covers, allow me to point out one of the dumbest things ever in all of audio is the bad habit all amplifier designers and manufacturers have of bolting down the large transformers to the amplifier chassis. I mean, come on people! Yes I realize transformers must be bolted down for shipping purposes. But the vibrating transformers should be decoupled from the chassis rather than strongly coupled to it. The best results will be achieved by isolating the entire amplifier from the transformer, even removing the transformer. The transformer can be decoupled using rubber grommets and loosening up the boots or removing them entirely. The transformer can be placed on viscoelastic squares of even placed on springs. But keeping them bolted down is like shooting yourself in the foot. Capacitors vibrate in operation so they should all be isolated from the printed circuit boards, etc. as well, or damped. It’s not really rocket science. 🚀 |
I’ve always suspected high end amplifier manufacturers were just about the farthest behind the audiophile power curve of any of the major food groups. They always seem to be the last to get the memo for just about every major audiophile development from fuses to wire directionality to power cords to transformer isolation or the myriad other tweaks and concepts audiophiles hold dear, from tiny little bowls to Rainbow Foil to Graphene to Mpingo discs, HEA designers are the last to find out, assuming they ever find out. Help me out, I can’t figure out, are they mildly retarded or are they just very conservative? 😀 |
Pop Quiz. That’s right, boys and girls, it’s time for another pop quiz! Yeah! Pop Quiz (3 parts) part 1 The Stereo Times article on the tiny little bowl acoustic resonators I linked to earlier this morning mentioned that the operation of the aforementioned tiny bowls was measured to extend as high as 3 GHz. How can these tiny little bowls that are about 7/8” diameter operate at frequencies up to 3 GHz? Hel-loo! part 2 One of the more incredible and puzzling aspects of the tiny little bowl resonators is how much they affect very low frequencies. How can three or four of these little guys do that? part 3 Another bizzare aspect of the tiny little bowls is they affect the sound even when they not located in the room. How can that be? |
