In my next version of the cube I will try very dense absorbtive foam
and not use wood. The gain of the boundary does not seem to be true
hemispherical. I have read reports on both sides of this. But I
figure if I keep using the very quiet mics types I really don't need
the boundary gain from what I am seeing in the field. I am just not
finding my mics with there high outputs can be driven to +60db on the
preamp. I would say the mics have too high of a noise but they are
out performing my ears so I can not complain.
Rich
--- In "John Hartog"
<> wrote:
>
> Hi David,
> It's important here to distinguish boundary from other barrier
techniques.
> For boundary mics the direct and reflected sounds that combine at the
> reflective surface give several dB of wanted free gain. For other
> barrier techniques, like a Jecklin Disk, an absorptive surface is
> ideal to reduce unwanted phase cancellation between direct to the mic
> and reflected off the barrier sounds.
>
> -John Hartog
>
>
>
> --- In Secomb's <secowlet@> wrote:
> >
> > Hi all
> > There have been a variety of DIY projects that have been floating
> > around. Which material that is used is essential component of any
such
> > project. I have been under the assumption that harder and smoother
the
> > material, the greater the sound would be reflected. To me Rich
making
> > a cube array with wood made sense but a softer material such as
high
> > density foam will result in less sound reflected towards the mic.
> The
> > concept of emphasising a particular range of frequency is
interesting.
> > A little while ago, a mouse pad was used as a Jenklin disk (I think).
> > Again a softer material with a slight texture will give less dB when
> > compared to wood for instance .
> > With those more experienced in sound recording is there a rule of
thump
> > what are the reflective properties of a variety of material that is
> > used in DIY projects. It appears not only the degree of sound that is
> > reflected to consider, the tonal quality is also important.
> >
> > David
> >
> >
> >
> > --
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19/05/06
> >
>
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