BillFitzmaurice.info

TimpBizkit wrote:http://www.youtube.com/watch?v=zMzws30ZluI
This time caused by the difference in arrival time from the mouth to 2 different microphones

Very cool man. Thanks for the link.

TimpBizkit wrote:http://www.youtube.com/watch?v=zMzws30ZluI
This time caused by the difference in arrival time from the mouth to 2 different microphones

That's not comb filtering. When the hand held mic is brought close to his mouth there's a major bass boost that's caused by microphone proximity effect.
They're selling something. Caveat emptor.

Bill Fitzmaurice wrote:

TimpBizkit wrote:http://www.youtube.com/watch?v=zMzws30ZluI
This time caused by the difference in arrival time from the mouth to 2 different microphones

That's not comb filtering. When the hand held mic is brought close to his mouth there's a major bass boost that's caused by microphone proximity effect.
They're selling something. Caveat emptor.

True about the bass proximity creating the extra low end. The other issue is phase cancellation that happens when two mics are picking up sound from a single source.

That video shows both things happening.....but, they totally blew the description of what's actually happening. It's not comb filtering as Bill says.

If you want a real world example of how to see the difference phase cancellation can cause - mic a snare drum on the top....then put another mic on the bottom. Bring up both channels and listen. Then flip the phase reverse on the bottom mic channel. You'll hear an instant volume increase and it really fattens up.

This happens a lot with micing choirs etc. with multiple mics. It's hard to catch sometimes....it just sounds dull and listless. Move 'em farther apart to overcome the cancellation......or just use two mics instead of three or four.

Here's a link to what Ivan Beaver and Mike Hedden of Danley Sound Labs will identify as "finger lobing."

The time effect on line arrays. This was a demo of a DSL Jericho (J1) vs. a Meyer Mina. Pretty cool.
http://www.youtube.com/watch?v=cPHpusei0jQ

That just shows to go ya' that you can skew data/tests to give just about any result. At the correct listening distance versus array height that does not happen. No one listens to an 8 box pro-touring array that close.

The issue with arrays is that it takes a certain distance from the array for the individual wave fronts from each element to coalesce into a single coherent wavefront. My 40 inch high TLAHs loaded with 4 inch woofers and 3/8 inch tweeters do so about eight feet out. A massive pro-touring array may need 50 feet. This applet shows how it works:
http://www.acoustics.salford.ac.uk/fesc ... fract4.htm

Cool. Plus, unless is the park is empty, no one is walking their way to the stage.

TimpBizkit wrote:http://www.youtube.com/watch?v=fbn2cGJHB9Q more comb filtering, love that phaser pedal effect!
Let him off, he's just testing!

That is comb filtering, and proves that no matter how much you spend it's money wasted if you don't know what you're doing.