Note to self. I still haven’t got an answer to my question why mechanical feedback in the audio system is dismissed, ignored or overlooked by tuners. Do tuners just sweep it under the rug?
Showing 45 responses by geoffkait
glubson catches on fast. Yes, the Sony Walkman is not (rpt not) susceptible to vibration. If you know what to listen for you can hear it. Way to go, glubson! 🤗 Not to mention my 12 ounce system does not have a whole lot of mass and stuff hanging off it to even vibrate. If you could hear what I hear with my ears.... |
I wood be remiss in not mentioning some other audiophile icons made of wood. The Shakti Halographs, Room Tuning devices, a classic. Shun Mook Spatial Control Kit (3 Mpingo discs on a wooden bracket. An awesome device. Shun Mook record weight, stack of dried ebony briar discs, very high on my wish list when my rich uncle gets out of the poor house. Shun Mook Diamond Resonators, audio footers comprised of a stack of ebony discs with a diamond tip, you know, for “instantaneous evacuation” of vibration. Me want. |
Michael, obviously my Sony Walkman and Sony Ultralight headphones system is not the same as “room listening.” However, I should point out that headphone listening, or “direct ear” listening as you call it, does have some very important advantages over in room systems. Let me list them for you here. I won’t dwell on COST SAVINGS, which is obviously enormous. I also won’t dwell on SPACE SAVINGS, either. Or even TIME SAVINGS. The primary advantage of my current system is SOUND QUALITY - purity, air, dynamics, coherency, and extremely low noise and distortion. 1. My headphone system is completely independent of room acoustic anomalies that plague room systems - echos, standing waves, comb filter effects, early reflections, phase issues,. I do not have to constantly tune my room, I.e., playing around with room treatments and adding/moving/removing them, as well as moving speakers to keep up with all the changes and tweaks. It can be an endless cycle, I don’t have to tell you. 2. I have no AC issues, or AC ground issues, since my system is battery powered. 3. I avoid the noise and distortion that accompanies power cords, speaker cables, interconnects, and digital cable. 4. I avoid noise and distortion that accompanies transformers, large capacitors and fuses. 5. I avoid distortion produced by speaker crossovers as my Sony Ultralight headphones are crossover-less. 6. I have greatly reduced the number of variables that affect my sound by going to a small, battery powered system. This makes things much easier to CONTROL. 7. Immunity to RFI/EMI. 8. Immunity to vibration. Quick Summary - More music, better sound, less audio nervousa. |
Getting back to Mpingo wood for just a second. I would have thought Tuners would be all over this thing like ducks on a June bug, jumping up and down at the mention of Mpingo wood or Mpingo discs. The Mpingo disc, African Rosewood + Gabon Ebony, and highly resonant, is a Tuner’s Delight. First it takes some considerable effort to find a place in the room where you get a Big Bang. Many of the suggested locations often don’t work or are overly subtle. This just seems like a Tuner’s dream. Once you get the hang of it there’ll be no stopping you. There are many locations in the room where a Mpingo disc will improve the sound. And what a sound! But the best part for Tuners is when you do find a location that works you can tune the disc since it’s directional. Hel-loo! If you have it upside down it won’t work and if you don’t have the azimuthal (rotational) direction tuned in it’s effects won’t be as pronounced. You can also play games with the soundstage with one or two Gabon ebony 12x1x1 stakes, or even rosewood, the kind they sell at hardwood stores. Just lean one or two ebony stakes up against the wall in various locations. A Tuner’s delight! 🤗 |
I realize MF is a big vinyl guy but geez, Louise, you can only get so much soundstage when you’ve got 10,000 records crammed into the listening room. No offense to anyone. I mean, come on! MF would be wise to place his entire record collection in a dedicated house or self storage unit somewhere and keep only what’s in current rotation in his listening room. That would put him miles ahead of whatever he’s got now sound-wise. Same goes for CDs, all you CD fanatics out there. They are bad for the sound - there’s no other way to say it. Am I even allowed to say that? Will I be banned for saying that? 😳 I have lived here before, the days of ice And of course this is why I'm so concerned And I come back to find the stars misplaced And the smell of a world that has burned |
My last concept for a isolation stand was a combination of viscoelastic material, bamboo and glass micro beads. Together these materials simulate the operational characteristics of the woodpecker’s head (bone, special absorptive tissue and flexible cartilage) which able to withstand tremendous negative g’s whilst pecking wood. Much greater negative g’s than a F-22 fighter pilot pulling a Immelmann maneuver. |
I probably mentioned this before somewhere - the type of wood matters much less when we’re talking about the top plate of an isolation stand. That’s because the top plate is isolated from vibration coming up fro the floor along with the component. Now, there remains residual vibration on the top plate - the percentage of seismic type vibration from the floor, acoustic vibration and vibration induced by the component (motor noise, transformer noise, etc.). Residual vibration can be dealt with effectively and easily using inexpensive damping techniques. No, not rubber, Michael! Also, all wood or granite or other boards or slabs should always be supported by cones. Carpets are an issue when placing iso stands on them because carpets behave like springs and can interfere with the performance of an iso stand. Cones that pierce the carpet are suggested. One issue with hardwood boards and plates that hasn’t been addressed so far is warping. Maple, aside from its sonic attributes, is very resistant to warpage over time. Other woods, like the cherry I used for the Nimbus isolation stand I built for Mapleshade Recording for CES, might not be so resistant. Cherry wasn’t. I also have used Baltic birch for load bearing sections of iso stands and Baltic birch ply for the top plate. I also like the high mass (inertia) and extreme stiffness (resistance to seismic type bending forces) of materials like granite and bluestone. At the Show in Vegas with Golden Sound I employed Italian marble slabs (beautiful stuff) made right there in Vegas, enough slabs for about five isolation stands, two slabs per stand, a spring sandwich as it were. 🥪 I have a customer in Aruba with a monster five foot long marble isolation stand for his Raven Turntable. I’ve also used laboratory grade granite slabs for some projects. 3” thick 18x18 Bluestone slabs from Home Despot are probably my fave, all things considered. One big advantage of my small independent springs is there is virtually no limit to the load they can handle. I have customers with seriously heavy things up on my iso stands. Upwards of 200 lb. My first iso stand, Nimbus was limited to a load of around 35 lb. |
midareff135 No wood here. I use sorbathane feet, spikes, lead weights and such. >>>>>You might want to peruse what I wrote earlier today here regarding Hard and Soft materials for use in audio situations. |
Glubson, there are steel coil springs, steel leaf springs, gas shocks, oil filled gas shocks, air springs. They’re all springs. To qualify as a spring they have to behave as a spring. And they certainly do behave as springs - otherwise they wouldn’t work. Proof by inspection. 🤗 I don’t mind running a class on remedial physics. |
Who is more obsessive compulsive, tweakers or Tuners? Let’s take maple platforms (boards) for example. You got your air dried maple from Mapleshade. You got your maple with grain running vertically and maple with grain running horizontally. There are varying thicknesses of maple, the thicker maple boards resisting bending forces better than thinner maple boards. There’s also the tricky issues of mounting the maple board and mounting the component on the maple or other material. So, what is the best way to mount the maple board and the component? The best way to mount the maple board (or any material) and the component is extremely hard cones. The harder the cones the better the sound - fuller, more open, more natural. As it turns out materials like aluminum 2.75 and carbon fiber and brass 3.0 and hardwood are actually relatively soft, on the Mohs scale of Hardness, where diamond is a perfect 10. Lead is 1.75. An excellent choice for cone material would be hardened high carbon steel 7-8 (like my Machina Dynamica springs) or NASA grade ceramic 9.5, both of which are quite high on the Mohs scale of Hardness. And we haven’t even talked about using springs with maple boards. The final frontier. |
glubson, please try to keep up with the conversation. I’ve been talking about the electrical signal, not the final acoustic signal. I trust you don’t think the final acoustic signal is not dependent on what comes before, you know, the electrical signal in the power cord, in the electronics, in the transformer, in the fuse, in the interconnects, in the DAC, CD player or turntable, and speaker cables. I don’t think anyone can be that obtuse. Not even you. No offense. |
glubson The issue that geoffkait, and maybe someone else, is clumsily bringing up is influence of some other environmental vibrations on those "pure" sound vibrations. They surely exist, try listening to music with or without jackhammering in the vicinity and notice the difference. Now, I will not go into how (un)noticeable tectonic movements would be during a movement of an amplified symphony. >>>>It all depends on whether you buy into the proposition that electrical signals in wire are vibrations. Apparently you do. It also depends on whether you buy into the proposition that the electrical signals in wire cannot be affected by vibrations from the floor, the acoustic waves or motors and such. Apparently you do. I’m rather shocked that you guys aren’t familiar with mechanical feedback. That’s the squealing you hear when the speaker cabinet vibration distorts the front end electronics. Gee whiz, isn’t that one of the first things beginner audio scouts learn when they start getting audio merit badges? If I didn’t viddy it with my own eyes 👀 I wouldn’t have believed it! Come on, guys! Let’s take the case that the audio signal IS a vibration, which it isn’t, but I’m going to humor you guys for a second. Even if the electrical signal IS vibrating don’t you think external vibration would affect the signal? Here’s an example. - consider the case of a car going down the highway with two (2) sets of shock absorbers for each wheel, one on top of the other. The external vibrations produced by the road surface would produce an extremely bumpy ride, not a smoother ride, as the two spring systems for each wheel would interfere with each other. It would be total chaos. |
michaelgreenaudio When you get to the place in your hobby that you start to realize the audio signal’s interacting with every thing around it a new hobby begins from that point on. >>>>Next step: get to the place in your hobby that you start to realize the audio signal’s interacting with the vibration that’s all around it. Then an even newer hobby begins from that point. There’s always another hill to climb. 🤗 Quick question: Did you ever consider why the sound improves when you take the big ol transformer out of the chassis and put it elsewhere in the room? You don’t think it’s just a question of lower mass, do you? 😳 First passenger, slightly inebriated, looking out the aircraft window: Hey, look, those people down there look like ants. Second passenger: Those are ants, pal. We haven’t left the ground yet. |
Jburidan Likewise, our friend geoffkait often misuses words and commits fallacies of equivocation. It’s no big deal, except that his posts serve to benight rather than to enlighten the reader. I’m not a physicist, but nevertheless even I know these simple things. >>>>I haven’t misused a word since 1975. Most likely the culprit is miscomprehension on your part. Have you given any consideration to going back to school for a physics refresh? Nothing is written unless I say it’s written. “If I could explain it to the average Palooka they wouldn’t have given me the Nobel prize.” |
tjbhuler Hi Geoff i just had a great listening and tuning session just now while commenting what i expreicned (sic) to Michael on what i did. Just to share what I did just now, I tuned the side walls and my floor by applying few pieces of wood beside the speaker stand and that brought out amazing image and better layering of my stage. I tensioned one of the bolts of my front wall and that brought out the stage more forward towards my listening spot. Now since you are a man of science and seems to be an amazing physicist would you care to comment on what is happening to my setup and tuning ? >>>>I was kind of hoping you or Michael would explain it to me. So far all I see is a lot of hand waving. By the way, in case I haven’t been clear, I don’t doubt that some or many or even all of Tuning principles don’t work. What I have been saying is those principles don’t go far enough. You know, what the the myriad problems produced by seismic type vibration as well as acoustic vibration and vibration from transformers, capacitors, motors, etc. follow? You guys can dodge and weave, ignore, Pooh Pooh, attack, evade, dispute all you want. It’s no skin off my nose. The arguments from Tuners against vibration isolation are either non-existent or incorrect. But I’ve said this all before. Something is fundamentally wrong somewhere with the whole Tuning manifesto, I submit, since Tuners embrace vibration, and want vibration to be free to roam anywhere, whereas most of the rest of the world embraces killing vibration. You are kind of the Branch Davidians of vibration. 😛 there’s a space between us big enough to drive a truck through. 🚚 |
Nope, same side. External vibration interferes with and distorts the electrical signal in wire. It does so whether the electrical signal is in the power cord, internal wiring, capacitors, transformers, speaker crossovers, speaker cables, interconnects, digital cable, what have you. As for the electrical signal in wire itself, it’s not (repeat not) vibrating. In an AC circuit it is alternating, but not vibrating. Follow? What you hear from the speakers under normal conditions is relatively distorted - unless you’ve taken steps to reduce or eliminate external sources of vibration in the audio system by incorporating a comprehensive program of vibration isolation and damping. That’s what I mean when I say, the only good vibration is a dead vibration. |
@jburidan when I use the term seismic vibration or seismic type vibration I’m referring to Earth crust motion (microseismic activity), as well as other very low frequency vibration produced by other sources, as I just explained. In urban areas cars, subways, buses, trucks are more important than Earth crust motion. Earthquakes are also seismic in nature, obviously, but they don’t occur very much so can be ignored. Follow? How can we be in agreement that seismic vibrations affect the tonearm and cartridge? You just said, “If tonearms and cartridges are engineered to have resonant frequencies circa 10-12 Hz, then it's absolutely illogical to conclude that isolating the turntable from seismic frequencies will reduce vibration of the tonearm and cartridge.” |
jburidan If tonearms and cartridges are engineered to have resonant frequencies circa 10-12 Hz, then it’s absolutely illogical to conclude that isolating the turntable from seismic frequencies will reduce vibration of the tonearm and cartridge. Whatever hocus-pocus you apply to your turntable, you won’t alter the resonant frequency of the tonearm and cartridge. Good rule of thumb: Don’t listen to your vinyl during an earthquake. >>>>>You must not have gotten the memo. Seismic frequencies include all very low frequency vibrations from footfall, traffic, subways, wind and the continuous microseismic activity, all of which affect the tonearm and cartridge natural frequencies. Earthquakes have almost nothing to do with it. Better luck next time. |
michaelgreenaudio If it’s not vibrating you would hear nothing at all. I personally have never seen or heard of an isolated audio system. I’ve only seen HEA marketing using the term isolation as a sales tool. Strawman argument alert! Obviously we’re not talking about the acoustic waves, at least I’m not. I’m talking about the vibrations that interfere or distort the pure signal produced by the speakers. This includes, again obviously, speaker cabinet vibrations, vibrations that interferes with the electrical audio signal running through power cords, fuses, wires, capacitors, speaker crossovers, etc. I’m not sure why some folks are so wrapped up on this false logic. It’s a mystery to me. Now, if by the word “tuning” you mean reducing vibration or changing the Fr by applying pressure I’m all for it. But, come on, people! Anyone who hasn’t gotten the memo regarding isolation of speakers yet is living in the proverbial Stone Age, gentle readers. This isn’t rocket science, folks! 🚀 The word isolation strikes fear into the hearts of pro audio enthusiasts. 👻 The only good vibration is a dead vibration. ☠️ Metaphors be with you! |
Ironically perhaps the type of wood is much less important when used as the top plate of an isolation stand due to the fact that the top plate is isolated right along with the component sitting on the top plate. Obviously, you still have to deal with induced vibration from motors, etc. as well as airborne vibration. But they are relatively easy to deal with by appropriate damping techniques. Marigo VTS Dots (constrained layer dampers), for example oh, and correct mounting techniques for the component and iso stand. Thus establishing a comprehensive vibration management program. Hint if you can’t decide on which type of wood to use, don’t fret as nice 3” thick slabs of granite or bluestone work very well, indeed, either as a support or as top plate for an iso stand. |
jburidan Isolating components from vibrations is an audio fetish IMHO that is exploited by charlatans marketing to the worst of the nervosa syndrome. Each object has a resonant frequency, and it’s going to resonate in the presence of that frequency, and there’s nothing you can do about it. You can change the resonant frequency, such as by putting sand or lead shot in a speaker stand, putting a bag of sand on top of a component, etc. >>>>Actually, there is something you can do about. That’s the whole point! Let’s take a straightforward example, shall we? Tonearms and cartridges are designed to have resonant frequencies circa 10-12 Hz. The reason for that is so acoustic waves won’t excite those resonant frequencies, as they well below the acoustic output of most speakers. But guess what? The range of Seismic frequencies which is 0 to 100 Hz includes the Fr 10-12 Hz so can obviously excite those resonant frequencies. You agree that’s not a good thing, right? So, isn’t it logical to conclude that isolating the turntable from seismic frequencies will reduce vibration of the tonearm and cartridge. No one ever said isolation is perfect but it’s a lot better than nothing. |
The oft mentioned analogy between an audio system and a musical instrument is completely wrong. A logical fallacy. The real analogy is between audio systems and electron microscopes. The audio system needs to be isolated from building structure vibrations for the same reason electron microscopes require vibration isolation in order to take photos of the specimen under the scope without the picture coming out all blurry. Unless you like your music blurry, gentle readers, better head on down to your local isolation store. The only good vibration is a dead vibration. RIP. And, no, speakers are not like guitars. Cabinets resonances are completely unwelcome in a high end system. Nor are the mechanical feedback from speakers welcome, either. I’m pretty sure we’ve known that since the 70s. Hel-loo! Wake up and smell the coffee, guys! ☕️ Go, ahead, give me your best shot. |
For audio cones there is a direct relationship between performance and hardness. Check it out. The Moh’s scale of hardness has diamond as a perfect 10.0 The best sounding audio cones are high on the Moh scale, less sonically effective cones are lower on the Moh scale. The NASA grade ceramics DH (diamond hardness) cones are right below diamond on the Moh scale. The Shun Mook Diamond Resonators use diamond tips on highly resonant Mpingo wood. Then we have hardened high carbon steel, with aluminum, carbon fiber and brass much farther on down the scale. Followed by soft rubber type materials, which by and large tend to store energy as opposed to allow energy to exist the system rapidly. https://www.alansfactoryoutlet.com/hubfs/hardness-of-metals-visual-representation-mohs-scale-5.png |
audionuttoo5 posts04-14-2019 10:04pmVisit anything to do with Michael Green Audio and you will learn much about the use of wood in audio to make proper use of those “good vibrations”! >>>>Hey, why be a shill? The discussion is right here on Audiogon. You’re welcome to join in. |
The entire building is vibrating. So, even if there were a material that didn’t vibrate much the component on the rack or platform would still be vibrating, right long with the entire building. Thus, the theory that wood is no good because it vibrates doesn’t hold water. The trick, gentle readers, is to decouple (isolate) the component from the building AND use very hard cone materials, I.e., not wood or carbon fiber or even brass, underneath both the component and the iso device to allow “residual vibration” to rapidly exit stage left. Cryogenically treated heat tempered steel would be a good place to start. |
I’ve had excellent results with maple and Mpingo discs which are Gabon ebony and African rosewood. But I agree with the previous post that wood can be tricky to work with. The reason you don’t see any cones made of wood with a couple notable exceptions is that wood is relatively soft and will therefore store more energy. Thickness is an issue when using wood for support as thicker boards will resist bending forces better than thinner boards. Note: thank goodness there are no more carbon fiber cones. No offense to anyone. Just commenting on the material, too soft and too funky sounding. |