Elevated sub woofer?

I’ve had a KEF KC62 for a few months, and it’s very, very good. After a few weeks of faffing around with positioning and orientation, I have it placed where I think it sounds best: on the floor in a particular place in my listening room.

Just reading some guy recommending elevating it, which I’m currently working out how to safely do, to test.

Anyone else do or done this?

The problem with elevating a subwoofer is that it makes it more difficult to attain secure placement on the ground. Room acoustics being what they are, it’s entirely possible though to find that certain designs may work better if you change the distance of the driver from the floor, in a particular room. However, in most case you should find that the manufacturers recommendation will work just fine. I find that starting out from a corner near the middle of a wall and then gradually moving towards the corner is a good way of finding the best position. It’s worth trying a different wall too as sometimes a particular wall will just work much better than another, including behind you. And don’t forget to try adjusting the phase…

1 Like

At the lower bass frequencies that are essentially omnidirectional a speaker, sub or otherwise, will be designed to work in one of a number of possible positions (based on an essentially rectangular room):

  1. free air (i.e suspended away from floor, walls and ceiling), essentially radiating spherically.
  2. half sphere = on floor away from walls, or against a wall away from floor, ceiling and other walls, or against ceiling away from walls.
  3. Quarter sphere = at junction between a wall and floor away from other walls, similarly junction between ceiling and wall away from other walls, or at junction of 2 walls away from floor and ceiling.
  4. 1/8th sphere = at junction of 2 walls and floor, or 2 walls and ceiling. (=Corner of room on floor or against ceiling.)

Within position types 2 and 3 the alternative locations can be swapped with nominally no difference to performance of speaker at those omnidirectional bass frequencies - so in theory a speaker designed for mid floor would be equally effective located mid wall (away from floor, ceiling or another wall) or mid ceiling, or one designed for floor against wall but away from other walls could be put at junction of ceiling an wall (away from other walls) or corner of two walls away from floor or ceiling.

However other room factors may have greater influence, making speakers sometimes perform better in positions other than those they were designed, and making it very difficult to predict effects of different locations. In other words try for yourself, and if it works well do it! Best assess by measuring using something like REW software and a measuring mic - quicker and more precise than just by ear, and facilitates phase alignment.

1 Like

I’ve got mine elevated, but that’s really only to dampen the vibrations going straight down to my downstairs neighbour. The position relative to the speakers was determined with the aid of REW, in a way that it compensates a little for the massive room mode I have close to 50Hz. For that compensation, it didn’t really matter if it was elevated or not. At the difference is not audible to me.

If that guy is Dennis Foley of Acoustic Fields then definitely take note of what he says.

Indeed, it was Dennis Foley.

I’ve tried a temporary elevated solution and yes, there’s something good going on here. I’ll have more time to compare with the previous on the floor position later in the week.

Interesting.

I have always had my sub raised from the wooden suspended floor to stop/reduce the bass being transmitted to my other equipment and causing vibrations. Initially I used an Aurelex Gramma platform designed for this purpose and it worked well but is not much to look at says the wife. I replaced that with a granite slab which also did the job. Recently as an experiment I replaced the 4 feet from the Velodyne sub with sub woofer designed feet made by SVS Subwoofer Isolation Feet which just screw into the threaded holes in the sub. They are very good sound wise.

1 Like

This topic was automatically closed 60 days after the last reply. New replies are no longer allowed.