naturerecordists
[Top] [All Lists]

Re: Binaural vs DSM microphone; here's DSM explained; patent link

Subject: Re: Binaural vs DSM microphone; here's DSM explained; patent link
From: Walter Knapp <>
Date: Fri, 07 Nov 2003 16:04:41 -0500
From: tony baylis <>
> 
> Thankyou for bringing this site to my attention, I
> have been away so have only just looked at it.  I do
> remember reading all I could find at the time c.15
> years ago, when I first started using my disk system,
> about various "Binaural Systems", the sources of which
> I have long forgotten.  There was a consensus then
> that there was no discernable difference between the
> systems using disks or dummy heads, something the
> Sonic Studios dispute.  I will have to listen to some
> recorded pieces on speakers and see if their claim
> holds up.
>   
> Tony Baylis.

I think we need to remember that these various mic setups are defined by 
the physical configuration of the setup rather than the sound we can 
record from them. If we start defining on sound quality the descriptions 
will actually have little helpful meaning as far as making a setup. In 
terms of what we call them, two mic setups can produce exactly the same 
sound quality in a particular recording instance, but still be called by 
different names. In some other situation the sound quality they produce 
may differ a lot, but their setup names do not change.

Call it binaural only if it meets the physical criteria for that mic 
setup. This has been greatly blurred by many folks who fail to 
understand that it is the name of a very specific mic setup, making the 
term less and less useful with time. A true binaural mic setup can have 
really awful mics in it, or really excellent ones. The sound quality 
will vary accordingly, but all will record true binaural, which has 
certain characteristics of it's own. In binaural you are carefully 
defining the sound path so that there is no overlap in sound path 
between the record and playback paths, and the soundpath is that of a 
unaided ear, it's as if the entire recording process changed nothing in 
the soundpath. At least in concept. I think it get's used a lot as a 
name because it's a more catchy name. But it causes great confusion to 
do so.

Two mics mounted somewhere on or near a real (or dummy) head is just a 
pair of near coincident mics with a baffle between, unless they meet the 
very specific requirements of binaural. Depending on how it's done, 
there can be considerable variation in the sound even with the same mic 
capsules.

The same applies between disks and dummy heads. Some dummy head setups 
are binaural setups, but not all are. A generic term is "head spaced 
stereo mics" for all these various setups. Then you have to define which 
one you are talking about. After all that also includes things like the 
SASS setups. Even the SASS setups come in two flavors. One, the original 
design, is a pzm setup with the diaphragms facing the barrier in a 
calculated gap that modifies frequency response characteristics. The 
second, which includes all the modified SASS, is a boundary mic setup, 
the diaphragm is even with the boundary facing outward. The sound you 
get from these two types is very close, but not quite the same, there 
are differences in the soundpaths. I have heard folks calling a SASS a 
binaural mic (I've probably even done that at some time), and it's sound 
has a lot of the same qualities, but not all. It's incorrect to call a 
SASS a binaural mic.

Once we have classified a hardware setup, then we can haggle over it's 
sound quality. And how much of that is due to the setup and how much due 
to the particular mics used.

I would certainly expect that there is some difference between dummy 
head and disk setups as to the particular quality of the sound. Stuff 
that's independent of which mics are used. Heck, there is a fair 
difference between the two modified SASS I have, and they differ only in 
which MKH mic is used, which is the other side of the coin. Enough 
difference that I'm still carting both around. Different dummy heads, 
and different disks will also give results that are not the same in the 
same way.

Of course it all depends on how picky you are and what sort of sound 
reproduction system you are using. For someone playing a boombox out in 
a noisy street they will hear none of these differences.

Walt







________________________________________________________________________
________________________________________________________________________



Your use of Yahoo! Groups is subject to http://docs.yahoo.com/info/terms/ 


<Prev in Thread] Current Thread [Next in Thread>
Admin

The University of NSW School of Computer and Engineering takes no responsibility for the contents of this archive. It is purely a compilation of material sent by many people to the naturerecordists mailing list. It has not been checked for accuracy nor its content verified in any way. If you wish to get material removed from the archive or have other queries about the archive e-mail Andrew Taylor at this address: andrewt@cse.unsw.EDU.AU