Thanks again everyone. Will checkout Clark Rubber and get the ball rolling.
Vicki, can I ask where you are based?
Paul
--- In vickipowys <> wrote:
>
> Hello Paul,
>
> I got my dark grey foam from Clark Rubber. My nearest store is Dubbo =
> (4 hours drive away) so I had to get it by mail order. Clarks
> describe the foam as 'high load' open cell foam. It seems to be
> about the same density as the original black foam in my Crown SASS. =
> Clark will cut the foam for you, but they are not always spot on with =
> their right angles or measurements! Better to buy larger pieces and
> cut them yourself, use a craft knife. Extend out a full row of new
> snap-off blades, and cut carefully along marked lines. An electric
> knife would be good but I don't have one. When you have cut the foam =
> to size and rounded the edges as good as you can with a craft knife
> and scissors, you can do a final smoothing touch up with very fine
> sandpaper. But you need to do all the actual shaping with the craft
> knife.
>
> cheers,
>
> Vicki
>
>
>
> On 27/09/2010, at 6:40 AM, thesilverloon wrote:
>
> > Hello Vicki,
> > Can I ask where you sourced the foam for your nosepiece?
> > The density that Rob suggests does not seem to be easily found.
> > Most open cell foams
> > that I can find have a far higher density than what Rob recommends.
> > I live in Sydney by the way.
> >
> > Paul
> >
> > --- In vickipowys
> > <vickipowys@> wrote:
> >>
> >> All,
> >>
> >> For my various SASS clones I have been making stretchy covers from
> >> lightweight lycra fabric, which protects the mics from a light breeze
> >> and is acoustically transparent. Over this I use a fine-knitted
> >> beanie without any high frequency loss that I could detect. I've
> >> also tried a loose-knitted mohair scarf, 2 layers of it, which is a
> >> bit better at wind protection than the beanie and lets through hf.
> >> As Rob says, fur fabric seems to cut out too much hf, I have found
> >> this as well.
> >>
> >> I am just now knitting a large mohair beanie (green!) for a DIY 'fur'
> >> cover that is designed to be acoustically transparent.
> >>
> >> If you wanted to make something even more windproof you could
> >> experiment (as Rob has done) with a shield about the size of a large
> >> hatbox but with fabric sides rather than cardboard. That way you
> >> would have say 6 inches of dead air space between the fabric walls
> >> and the mics. Maybe try one of those collapsible laundry/ garden
> >> baskets and re-do the fabric? Endless possibilities!
> >>
> >> Vicki
> >>
> >>
> >> On 25/09/2010, at 3:57 PM, Rob Danielson wrote:
> >>
> >>> At 1:42 AM +0000 9/25/10, thesilverloon wrote:
> >>>> Rob, thanks for that info.
> >>>> There's now no good reason not to build one.
> >>>> Maybe except for one. Wind protection. How well can they be baffled
> >>>> against the wind?
> >>>> The original windsock supplied by Crown, would not appear to be
> >>>> that
> >>>> effective.
> >>>
> >>> The stretchy material cover works pretty good until the wind gets
> >>> into 15+ mph range. Vicki Pows adds a wooly layer to the stretchy
> >>> material she can comment about. A single layer of burlap in a full
> >>> surround of dead air is working pretty well for me up to about 25-30
> >>> mph. I couldn't get fake fur to work in proximity to the SASS body
> >>> without too much HF loss. Rob D.
> >>>
> >>> =3D =3D =3D
> >>>
> >>>
> >>>> I would be mounting my AT 4022'S into this setup if I were to
> >>>> build one.
> >>>>
> >>>> Paul
> >>>> --- In
> >>>> <naturerecordists%
> >>>> 40yahoogroups.com>
> >>>> Rob Danielson <type@> wrote:
> >>>>>
> >>>>> Hi Paul--
> >>>>> Can one make a baffle using high-density foam that will provide
> >>>>> comparable or indistinguishable performance? Its definitely
> >>>>> doable.
> >>>>> There are several types of high-density, _open cell_ foam out
> >>>>> there.
> >>>>> I tested four or five kinds and found they did pass pink noise =
> >>>>> with
> >>>>> very slight differences. A neat aspect of foam baffle is it
> >>>>> cleanly
> >>>>> passes some sound energy under < 1100Hz to the off-side mic.
> >>>>> These
> >>>>> frequencies are critical for time arrival differences. Michael
> >>>>> Billingsley doesn't mention this aspect of the baffle in his SASS
> >>>>> patent as far as I can tell. Would different types of foam make
> >>>>> audible differences? All we need to do is make some up and
> >>>>> compare
> >>>>> them to find out.
> >>>>>
> >>>>> Cutting and sanding the foam to fit snuggly into the crown
> >>>>> housing
> >>>>> would take some time. Vicki Powys discovered that sanding is a =
> >>>>> good
> >>>>> way to get the final shape and dimensions.
> >>>>>
> >>>>> Any open cell foam that has a density of 1.5 to 1.8 pounds per
> >>>>> cubic
> >>>>> foot and is at least 4 inches thick should perform to
> >>>>> Billingsley's
> >>>>> high frequency absorption specifications. I use "charcoal gray"
> >>>>> acoustic foam. A 10" X 10" X 4" piece should be sufficient to
> >>>>> make
> >>>>> a SASS baffle replacement. Measure twice, cut once. Rob D.
> >>>>>
> >>>>> =3D =3D =3D =3D
> >>>>>
> >>>>> At 11:27 PM +0000 9/24/10, thesilverloon wrote:
> >>>>>> Does anyone know how important using the correct foam for the
> >>>>> nose piece is?
> >>>>>> One can buy just the foam nose piece from Crown as a spare part,
> >>>>>> and
> >>>>>> then build the rest.
> >>>>>> Thats still $100 landed in Australia. But if any closed cell foam
> >>>>>> would work,that would make the project that more do-able.
> >>>>>>
> >>>>>> Regards,
> >>>>>>
> >>>>>> Paul
> >>>>>
> >>>>>
> >>>>> --
> >>>>>
>
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