[sidders]

Would a 244 4 inches from the wall, do a similar job to a monster flat on the wall?

Thanks.

[Glenn Kuras]

mmmmmmmm that is a very good question. My guess would be no. Fiberglass absorbs more then air. Might start to get close though.

[sidders]

Thanks Glenn.
                 Are there any plans for a monster version of the freestand?

[Alex Reynolds]

Thanks Glenn.
                 Are there any plans for a monster version of the freestand?

We can do a custom one. Note that the FreeStands have thicker wood on the sides than the wall mounted panels, so they're heavier and putting them on the small feet for the FreeStands they may be a bit flimsy if we made them large.

[Glenn Kuras]

Thanks Glenn.
                 Are there any plans for a monster version of the freestand?

We could do it, but if you have carpet you would have to be careful. The feet are a fixed length so there will not be as much support like there is on the 2" and 4" ones. Also because it is larger the shipping would be a bit more. Email me though our website if you would like a quote.

[JoshK]

mmmmmmmm that is a very good question. My guess would be no. Fiberglass absorbs more then air. Might start to get close though.

Funny, I am no expert on this, but the physics would suggest it would work better, as in do more further away from a wall then right up against it.   Since essentially we are talking about standing waves within a finite space, the wave dynamics would suggest that up against a wall you have the least amount of airflow, so the trap isn't very effective at impeding the standing wave.  Out further from the wall air velocity is no longer static, thus air flows and the trap is more effective.   I think this is why Hemholtz radiators have to be out into the room.

I'd like to ask someone like Dr Geddes his take on this.  I have heard it said a few times that traps in the corner actually do the least good contrary to standard audiophile beliefs because of this depending on whether you are trying to trap LF or HF.   Corners are bad for HFs obviously, but traps in corners isn't going to do much for bass issues because of the highest pressure lowest velocity problem.  Traps require air moment, i.e. velocity to be effective and do nothing for pressure. 

I've seens some papers by the BBC and Canadian national center that showed this. 

[Glenn Kuras]

Well your thinking is right, but even with a trap just a few inches away from the wall it helps a lot. 

As far as corners that is the reason we straddle corners or make the bass trap large when it is broadband. The further out the lead edge the better the performance, but there is also a  point that you can do this.  Basically fiberglass is going to absorb more then air so thicker will most always trump just leaving a large air gap. 

[JoshK]

Thanks for the response.   I am still learning all this stuff. 

[Alex Reynolds]

A bit older of a thread but just wanted to clear up something..

Funny, I am no expert on this, but the physics would suggest it would work better, as in do more further away from a wall then right up against it.   Since essentially we are talking about standing waves within a finite space, the wave dynamics would suggest that up against a wall you have the least amount of airflow, so the trap isn't very effective at impeding the standing wave.  Out further from the wall air velocity is no longer static, thus air flows and the trap is more effective. 

Yes, you get more efficiency when the device is farther from the wall, but a panel that is less thick will not dampen the wave as much, either. Also, sound moves slower through fiber, which changes the point of maximum efficiency (a little).

I have heard it said a few times that traps in the corner actually do the least good contrary to standard audiophile beliefs because of this depending on whether you are trying to trap LF or HF.   Corners are bad for HFs obviously, but traps in corners isn't going to do much for bass issues because of the highest pressure lowest velocity problem.  Traps require air moment, i.e. velocity to be effective and do nothing for pressure. 

This isn't due to beliefs, it's due to measurements which always show increased efficiency in the corners for absorbers. The velocity is at a minimum at the actual boundary but even a small bit off still shows more absorption than this view implies. The interaction is a bit more complicated because room modes terminate in the corners, which makes the velocities much more distributed than they are in the middle of the wall.

I've seens some papers by the BBC and Canadian national center that showed this.

Could you please link? AFAIK I have all the BBC R&D reports and their Guide to Acoustic Practices and have never seen them mention that corner absorbers are somehow bad performers. Of course, this isn't to say that pressure based devices work very well in areas like corners, or even more efficient, but velocity based absorbers still perform very well in corners.