Posted by: "stoatwizard"
>>> Ok, so what happens when you take a copper tube and just screw the
>>> math and start cutting slots into it to build a interference tube
>>> shotgun mic?
>
>
> don'tcha have to cut about 50% of the material out of the tube, ie wide
> slots not skinny? I could see your saw blades won't appreciate that,
> but take a look at a Sennheiser MKH70 or even the ME64 and you see the
> slots seem to be as wide as the non-slots. Might help the frequency
> response. There agan I know jack about the maths - it's just an
> observation from every shotgun mic I've ever seen.
The slots are probably easier to cut with a milling machine where all
diameter of cutters are available and extreme control is available, but
not everyone has one of those. I suspect the commercial interference
tubes are cut on a CNC setup. Which is a computer controlled milling
setup. Train it once and it will churn out the precise shapes fast.
There is a lot of variation in the holes in shotgun interference tubes.
Which to me indicates it may not be as critical as it seems. The metal
of the tube could be important too.
I plan on someday doing the multitube setup just to see what it's like.
It's math is a bit easier to understand.
Walt
|