So the laws of physics appear to have stopped working - cab response on stool vs on floor

noisepolluter

I’ve had my closed back, ported 1x12 up on a small wooden stool for playing at home because Any Fule Kno that having the amp up a bit more level with your fizzog means you can hear the high end more clearly. 

I put it directly down on the carpeted floor (albeit slightly further away) and suddenly not only am I getting much deeper low end, as expected, but the high end also seems more extended and prominent. I wouldn’t say the centre of the speaker is pointing more directly at my ears, if anything it’s less direct an angle.  

Anyone able to explain what’s happening? I’d previously just assumed that the cab itself was a bit dark sounding but now it’s clearer and punchier in a position where I’d expect it to be less clear. 

Perhaps with the amp on the stool, the wood of the cab is coupling directly with the wood of the stool and creating some kind of odd resonance with the space underneath, that appears to be cancelling some of the bass and treble from my perspective? 

Or with the amp on the floor, is the more efficient bass coupling dropping the overall resonance and un-gumming the low mids thus making the high end more clearly audible?

I should also add that the cab does have relatively tall rubber feet which keep it clear of the carpet by a couple of cm.

Nerine

It’s likely mostly room acoustics and boundary effects. Putting the cab on the floor will reinforce the low end, but changing the cab height also changes how reflections and cancellations interact at your listening position. Frequencies that were partially nulling on the stool may no longer be nulling on the floor, making the cab sound both fuller and clearer.

Winny_Pooh

Facing the centre of the cone to your ear produces the most treble. I'd try again until you figure out what's actually happening.

noisepolluter

Tried putting the amp on the stool in a different spot in the room and it was much clearer, so it must have been some kind of cancellation in the original spot. 

Nerine

For logistical purposes it’s sometimes easier to leave the amp where it is and move to a spot in the room where it sounds cool. 

BillDL

If you slice a rectangle out of your carpet and fill it with cement and swap the amp's feet to running spikes you would probably hear the inherent tone of the cab rather than as influenced by the carpet or the stool.  Keep the carpet cut-out in case you discover that placement and relative wall position was causing the difference in sound after all  

fretmeister

Direct contact with the floor is less important than many believe.

The issue is the boundary effect / wave form and the proximity to the floor. It's more obvious on bass cabs due to the longer waveforms.

A bass cab is still "coupled" to the floor * when it's nearly 3 feet off it.

* = boomy nonsense from hollow stages is a different problem

ICBM

fretmeister said:

Direct contact with the floor is less important than many believe.

The issue is the boundary effect / wave form and the proximity to the floor. It's more obvious on bass cabs due to the longer waveforms.

A bass cab is still "coupled" to the floor * when it's nearly 3 feet off it.

In theory… but in my experience that’s not true in practice - even a few inches up off the floor makes a noticeable difference, both good for guitar cabs and bad for bass. Three feet would completely change the sound. I always prefer guitar cabs up off the floor and bass cabs fully down, it really helps give a natural mix that rolls off the bottom end of the guitar and stops them fighting over the same frequency space (and prevents volume wars).

Putting my little Roland Micro Cube Bass on an angled stand so it was a few inches off the floor totally killed the bottom end. I thought it would make it easier to hear but it just sounded thin… it doesn’t when it’s fully down.