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Re: some questions about equipments.

Subject: Re: some questions about equipments.
From: "revery" reveryus
Date: Sun Oct 13, 2013 12:21 pm ((PDT))
I'm using an MKH30 as the figure 8 which is a side address mic so it's length 
points the same way as the 8040's.
I'm definitely going to give it a try. Some mechanical stuff on getting the 
multiple cabling through the windshield system still to be done, plus the 
taping together'.

Scott, I'm using SpectraFoo to measure the sample offset only. Correction is 
done by shifting the microphones relative positions physically.
The microphones sound interesting, but I'm already poor after the Sennhiesers!

Thanks to you both.

Ray.

On 14/10/2013, at 12:25 AM,  wrote:

>> For single MS, I use SpectraFoo to compute the delay between between the M 
>> and S microphones ad try to adjust their positions so that is 1 or zero 
>> samples. Perhaps that is overkill, and maybe say an overlap of 0.5cm can be 
>> achieved for taping overlap (giving a coincidence error of .25cm either side 
>> of the S capsule) would not be too bad? A full wavelength at 10KHz is about 
>> 3.4cm but I would think even a quarter wavelength non-coincidence is going 
>> to give some significant effects (.85cm)? 
> 
> Ray, 
> 
> I did some experiments for a stereo article, and with white noise bandpass 
> filtered around 1kHz, 3 samples were about the minimum to produce a stereo 
> shift. However, at a path length difference between two mic capsules, 
> equivalent to 3 samples (23mm) the first extinction frequency is about 7kHz, 
> so that is more of a priority with a multiple mic rig than stereo placement. 
> 
> It depends on what you are recording, but you may well get away with a 
> "notch" like that within a stereo image as there are larger effects in many 
> commercial stereo setups - ORTF for one example. That works as our ears 
> "interpret" the effect, but with sum and difference matrixing as with double 
> M/S, it may show up at important directions. 
> 
> What are you going to use as the fig-8 element for the double M/S? The 
> problem with the MKH30 is that it is end-on and will thus stick out 
> sideways. 
> 
> David Brinicombe 
> 
> 
> 
> 
> ------------------------------------
> 
> "While a picture is worth a thousand words, a 
> sound is worth a thousand pictures." R. Murray Schafer via Bernie Krause.
> 
> Yahoo! Groups Links
> 
> 
> 







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