Date: Thu Jun 16, 2011 4:45 am ((PDT))
I hope this will help
I put ms mkh 30/40 in a fiber glass 65cm parabola that I made and the focus=
of the parabola was the line in the limit of the parabola not inside the p=
arabola, in the limit.
--- In "diesel33dsl" <> wrot=
> Thanks all dudes!
> Most of your answers can be synthesized with a 'try it and see' basis.
> Thats what I'll be doing then, once I have gear and mikes enough to make =
comparisons (and software and measurement tools too, we could give some wor=
ds here also about what tools you use).
> It is a pleasure to read your debates and opinions, specially now I am st=
arting to take it seriously.
> About using parabolas, i guess my decision is to gather some coins and tr=
y to ask one of those swedish to send me a telinga set :)
> Positioning a shotgun mic in a parabola seems quite an unexpected go sinc=
e I'd be combining two different caption ideas (thanks David B.) and probab=
ly locating the capsule in the focus is not easy due to mike size and so on=
... I guess the same happens when trying to locate there two isolated mics =
for a stereo take of a distant element.
> Thanks Raimund also, your Goshawk take makes worth the try with my approa=
> What's clear is that small/light mikes will fit best there and omnis poin=
ting to reflected sound are best choice...
> i guess the Telinga sets include good mikes on them, specially designed f=
or better performance, but has anyone of you got better results by swapping=
default Telinga mikes with others?
> Or, is my choice to get a Telinga set (dish, handle, mount) without mikes=
and put some specific models there?
> Which models/brands go well here?
> --- In "Avocet" <brini@> wrote:
> > > Question 2:
> > Is the parabola approach designed to be used with JUST omni mics?
> > Are other caption patterns allowed, or is it senseless to use
> > directional mics here?
> > Dani,
> > As a supplementary answer, try any mic with a parabola and see what it
> > does. However, bear in mind that a double mic or a gunmic will be
> > wider or longer than the high frequency focus of the parabola so the
> > basic parabola theory won't apply.
> > > Does this enhance directivity for a shotgun?
> > You would be combining two very different directional principles and
> > it is unlikely that they would reinforce each other's characteristics
> > but try it. And it is likely that they would reinforce each other's
> > disadvantages.
> > BTW I regard the MKH 416 one of the most useful mics available and
> > can't see how it can be improved on except for the MKH 816 (still
> > available second hand). If you have a bottomless pocket there is the
> > MKH 8070 which has an amazing spec but I can't afford two of them for
> > stereo. :-) I think the law of diminishing returns would act here,
> > money-wise.
> > Going to basic parabola theory:
> > a) The focus is finer at higher frequencies and virtually non-existant
> > at low freqencies.
> > b) An omni mic will pick up both direct sound and reflected sound and
> > at some frequenies these will tend to cancel out, but for most wanted
> > frequencies the reflected sound swamps the direct.
> > c) A cardioid theoretically avoids cancellation effect type b) but
> > other diffraction effects still apply. A cardioid is always more
> > susceptible to wind and handling noise. Take your pick on
> > disadvantages.
> > d) Stereo with a parabola is only possible using two points just
> > off-focus on either side. The theory behind this is complex so trial
> > and error is the best method of finding out what works.
> > David
> > David Brinicombe
> > North Devon, UK
> > Cogito cogito ergo cogito sum - Ambrose Bierce