Subwoofer / Low Frequency Optimization

[ohnonotagain]

And a reoccurring diagram (because I'm a visual person).

https://ledgernote.com/reviews/best-studio-subwoofers/

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In an attempt to correct a nasty bass null at 79Hz in my desktop listening setup, this is how I ended up with a subwoofer attached to the underside of my desk.

Now, the diagram I can understand. I don't quite get why having the sub attached to the underside of the desk firing forward instead of on the floor firing down made such a difference to the bass null - it didn't make much of a difference to the rest of the frequency range - but it brought it within a range where EQ can take care of the rest without horrible clipping.

 

[ThatSoundsGood]

In an attempt to correct a nasty bass null at 79Hz in my desktop listening setup, this is how I ended up with a subwoofer attached to the underside of my desk.

Now, the diagram I can understand. I don't quite get why having the sub attached to the underside of the desk firing forward instead of on the floor firing down made such a difference to the bass null - it didn't make much of a difference to the rest of the frequency range - but it brought it within a range where EQ can take care of the rest without horrible clipping.

How high off of the ground is the sub? Moving it away from the floor can have the same effect as moving it away from the walls.

 

[ohnonotagain]

How high off of the ground is the sub? Moving it away from the floor can have the same effect as moving it away from the walls.

It's attached to the underside of the desk, so at a height of about 70cm. One might think that the desk would behave in a similar way to the floor, as it's about 6cm thick and pretty solid.

 

[ThatSoundsGood]

It's attached to the underside of the desk, so at a height of about 70cm. One might think that the desk would behave in a similar way to the floor, as it's about 6cm thick and pretty solid.

It's going to be less about the thickness and more about the distance between the sub and the floor/walls. There might the some resonances in the desk and floor but we're really dealing more with 1/4 length and 1/2 length waves in the room.

 

[richardm]

In an attempt to correct a nasty bass null at 79Hz in my desktop listening setup, this is how I ended up with a subwoofer attached to the underside of my desk.

Interesting... My primary sub is under my desk. Looking at REW's room sim, lifting it 2-3ft off the floor cleans-up a bunch of the "crap" happening north of 50Hz (shows up on the sim in addition to real life). Unfortunately it pushes a massive suck-out at 40Hz down to 30Hz without correcting it in the slightest.

This has me pondering a swap... Putting a secondary sub under the desk and moving the main somewhere else. My secondary is actually a modified, re-purposed 3-way speaker. I could stick it under there upside down which would elevate the driver off the floor. I must try this...