Vibration - What are the Main Sources?
All things in our universe are constantly in motion, vibrating. Even objects that appear to be stationary are in fact vibrating, oscillating, resonating, at various frequencies. Resonance is a type of motion, characterized by oscillation between two states. And ultimately all matter is just vibrations of various underlying fields. As such, at every scale, all of nature vibrates Sorry but I can’t post the link to this. Phones is so stupid |
Meantime: practice makes perfect. A major source of vibration distortion is generated within the component itself. The entire audio signal is itself a vibration, oscillating back and forth positive to negative just constantly vibrating one transient after another. Everyone knows about the transformer that physically vibrates when there is DC offset. No one stops to wonder, why does the transformer vibrate? It is after all just electricity going through it. So we only notice when it gets real loud and annoying. But the same thing is happening all the time everywhere constantly the whole time the component is turned on. Not just in the transformer either. Everywhere there is a music signal, there is vibration. People tend to be real superficial and see only the obvious. Speakers vibrate- it must be the speakers! https://youtu.be/eXRM3lFRwRI?t=3 We need to look a little deeper. The real detail we are looking for in recreating music is extraordinarily fine low level detail. The smallest squiggles on a record are on the order of the size of a large organic molecule. Even by the time they are amplified to a very high volume level still it is not enough for anyone to see a tweeter moving back and forth. Yet it is. Same thing in our components. They all vibrate, even supposedly no moving parts DACs, preamps, and amps. If speakers are the problem then why does vibration control work with headphones? Riddle me that one, Batman. So the whole component is vibrating. There are a couple ways we can deal with this. One is try and control it at the source. That is why so many expensive high end components use beefy construction, thicker circuit boards, and so on. This is a form of vibration control. You can also apply materials like TA-102 fO.1 tape inside, directly on the chassis, boards, caps, etc. This works great. But too much trouble and risk for most to bother. We can use things like cones, spikes, various footers, mass loading, shelf and rack construction, etc but all these things really do is shift or channel the vibrations into resonating at different frequencies. Some try and shift this into ranges we are less sensitive. Lots try and fool us into thinking the ringing we are hearing is actually improved detail. Lots and lots of them work exactly this way. Almost all in fact. The exception, other than super expensive laboratory gear, is springs. The ringing so many misinterpret as detail is actually component vibrations going into whatever the component is sitting on, exciting that material to vibrate in sympathy, which then in turn vibrates right back into the component. The component, the shelf, rack, floor, the whole system is then vibrating, ringing. You can see this quite clearly on the seismograph iPad in this video. https://youtu.be/7ew4dRUEm-k?t=30 Please note where he says this is a concrete floor. So much for the idea concrete is some magic solution. It is not. All concrete does is channel the vibrations and transmit them faster than other materials like wood. There is nothing special about concrete. In fact it rings a lot worse than wood! Don’t take my word for it, watch the video. DYODD. Putting the component on springs does not prevent anything from vibrating. What it does do is isolate the component from its environment. This has two very important benefits. First, it allows the vibrations generated within the component itself to be dissipated within the component itself. This greatly reduces vibration distortion by eliminating ringing interactions with whatever it is sitting on. And secondly, it isolates the component from vibrations generated elsewhere in the room, such as by the other components. Speakers benefit hugely because they obviously generate the largest amplitude vibrations. Large enough to excite the entire room into vibrating resonant behavior. This is something that is very hard to appreciate until you put them on some Townshend Podiums, then it instantly becomes very obvious. A surprisingly large proportion of what people consider acoustic or "room problems" is in reality due to mechanical vibrations from the speakers exciting the floor, walls and ceiling. So there you go. Maybe one of the haters is having second thoughts and might want to get off the silent treatment and join the civilized world. Go through all my posts, organize them by subject matter, send me the spreadsheet or whatever. Do a good enough job I may even cut you in on a slice of the profits when we turn it into a book. May. I did say "may". |
With something like photography it’s obvious that keeping the camera as still as possible is of great benefit. You only have to look at 100 year old photographs to see just how much detail any camera on a decent tripod can capture. With audio playback the vibration phenomenon seems less clear. For example, with equipment that has no moving parts, are there any measurements that can reveal differences between signal output between isolated and non isolated products? Of course there are plenty of measurements detailing the differences when it comes to mechanical devices such as loudspeakers and turntables. Those devices have by far the highest rates of measurable distortion and by nature must also produce vibration of their own accord. To this day some will insist that belt drive turntables have the advantage over the so called direct drive because the isolation properties of placing the rubber belt between the motor and the platter. In my experience there’s no doubt that some form of resonance control is essential when it comes to speakers and turntables but the rest I’m not so sure. For me there’s also no doubt that solid floors in buildings situated away from busy main roads must be of great advantage. Unfortunately I don’t have those advantages, but I have heard systems in rooms where they have. The result is usually a palpably cleaner sound. With or without any additional isolation. It's also worth bearing in mind that most HiFi equipment does come with some form of prior decoupling, usually it's the almost ubiquitous rubber feet. Therefore it can get tricky to work out whether you might need some more, and if so, just how much more? |
