I am trying to reorganize my equipment since my search for an above TV shelf for my equipment is not working out too well. As I was moving my Sub I was wondering how close to my equipment I should consider placing it. Does the vibration created by a sub threaten audio equipment, TV, speakers etc ?

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Desperado - 1050 Owner - Reviews - Harmony SST-659 Remote

I would think the general rule here would be that if the equipment "rattles," you're too close.

There are some big proponents out there of "vibration" control of all equipment. Take note about how many audiophiles spend tons of money on doodads that float their equipment to get them to the next stage of nirvana. For turntables, this makes sense. For optical disc players, yeah, ok. For amps....well, the jury is out on that one.
In other words, I would try to keep your sub from directly blasting on top of your equipment but as long as you're not completely rattling anything, IMHO, you should be good.

Getting too close to your TV is another issue because most subs use big magnets on their drivers. Thus, keep well away from all CRTs. Projectors and plasma screens should be immune from this issue.

As a side note, I have a friend who added isolation devices under EVERYTHING in his system and swears it was the best move he ever made. FWIW, I think it made his system sound a little sterile if anything else but that's probably more related to his new SACD player than anything else.

you could get yourself a dB calibration meter and test it out. i have just recently put my sub on a stand, i would say deisolation platform, but i made it custom for my sub so stand it is :-); and i have noticed a little less bass. now this could be because i (or the sig. other) adjusted a knob accidentally, etc. or i dont have it in exactly the same spot, but as i have to make some minor adjustments to the stand, i will test my theory out. even if it does sound a little thin, i did save it from possible water damage since our water heater just crapped out and water spilled out during its replacement right where my sub would have been about 1/4" off the floor. i still dont see why velodyne put on these cheap plastic over-sized thumbtacks on their top sub (well top two years ago), however i do see now that they have provided feet. my stand/platform is pretty spiffy and it cost about $10, and looks like about $300. well to answer your question about placement, i would put it where it sounds best and vibrates the room the least. obviously never by a door, window, or hallway if possible.

also, i needed a stand for height adjustability more than i needed it for deisolation. our flooring is pretty out-of-level in some spots and was where my sub is, so i needed to be able to level it, hence the stand. most subs are magnetically shielded these days.

[This message has been edited by curegeorg (edited March 31, 2004).]

The bridge on an acoustic string instrument serves to couple the strings to the sounding board at a particular point. The design of the bridge can determine how effectively different types of vibrations are transferred from the strings to the sounding board. The construction of the sounding board determines how well it responds to various frequencies.

Any loudspeaker has at least three means of putting acoustic energy into a room. Its main means are the driver(s) and/or port(s). To a lesser extent, however, the vibration of the surfaces of the enclosure and the vibrations transferred from the enclosure to other surfaces, which in turn vibrate, also contribute to what you hear.

A subwoofer sitting on carpet is, for the sake of vibration, partially coupled to the floor. If your floor is a poor sounding board at low frequencies, “spiking” your sub to the floor increases that coupling and will allow extraneous vibrations to be dissipated. This can be a good thing. If your floor is a good sounding board at low frequencies, coupling with the floor may help or hurt the overall sound, depending on how the flooring reacts and how that interacts with the room and the sound coming from the sub itself.

In my case, isolating the subs from the floor helped in two ways. One, I liked the resulting sound better. I have no empirical data to pinpoint what changed exactly, so I can’t state with certainty that I have less erroneous acoustic information in the room, but that is my guess. Two, because I live in an apartment building, having less energy transferring to the floor means I disturb my neighbors less.

I isolated the subs from the floor by placing them on top of two other surfaces, one “mushy” and the other “stiff but springy.” This brought the sub about three inches above the floor.

Some people have a combination of things to deal with vibration. They may couple a sub, perhaps via spikes, to an object with sufficient mass to provide some damping of vibration while at the same time isolating both the mass and the sub from the flooring by means of material or materials that have some “give” in it.

A word about isolating or dampening non-acoustic devices, such as processors or amplifiers, from potential acoustic vibration: if you, by means of spikes or whatever, couple an amplifier to a surface that is vibration prone, you may actually be increasing the internal vibrations within the device you are seeking to protect from vibration. Spikes and other means that increase physical coupling allow a more effective transfer of kinetic energy from one object to another – in both directions! Depending on where the vibration is coming from and where it is going, this may help, or it may hurt, or it may not have any resulting effect on what you hear at all. If my vibrating floor is causing acoustic problems, coupling a massive amplifier to the floor may not help the amplifier, but it might improve the sound by changing the vibration behavior of my floor! (I have purposefully not coupled any of my devices to the floor any more than is necessary to support them, and in some cases made an effort to isolate vibration, not transfer it.)

When people tell you how a certain device or tweak will help, you’ve got to take a few minutes to think about what that device or tweak will do, or won’t do, or will do differently than expected in your particular situation.

Have some fun finding out what works for you. An example from about a year ago in the saloon: someone noticed something wrong with a rear projection television image in conjunction with sound from the center speaker resting on the top of the television. Both electrical/magnetic and mechanical/vibration issues were discussed. How to tell which issue was the culprit? I suggested placing a folded towel between the center speaker and the television. This would physically de-couple the vibrations of the speaker from the television, but not affect the electrical/magnetic interaction. The towel cured the problem, showing that it was vibration and not electrical emissions that caused the problem. Now that the problem and cure were known in principle, a vibration isolation tweak that looked better than a folded towel was purchased. Money was not wasted trying many different things.

Do some experimenting with placement and such. Have fun and be safe doing it!

I had mine set in front of my RPTV and it actually shook the picture out of alignment.
I moved it. :-)