Digital Phase Manipulation (0 to 360 Degree) Demos

[Skrasms]

I put together two little programs to show a couple points about uniform phase shifting.

A lot of people use tools like the IBP or uniform phase shifting plug-ins to fix problems with sounds recorded ?out of phase.? The sound we're all so used to when two mics picking up the same instrument at different times get mixed is comb filtering. It creates notches and peaks in the frequency spectrum (I'll spare the math for now ). Simple phase shifting does not remove comb filtering! It does, however, allow the filtering action to be shifted around. I made this interactive program to show that at work:

Download Here

The second program is to answer whether or not this kind of phase shifting itself is audible. In the program above you can hear big changes because it affects the way two signals are interacting. What happens when uniform phase shifting happens without any reference? The frequency spectrum isn't changing, so what is there to hear? On signals like square and sawtooth waves, the internal relationships of harmonics get altered audibly. On the other hand, try playing a wave file of a real instrument and listen for any difference at all.

Download Here

Hopefully there is something to learn from all that. Let me know if I can make anything clearer.

[Skrasms]

It looks like there haven't been any downloads. Here are a couple screen shots of what the programs look like:




They don't require installation, just unzipping. They should be completely self-contained.

[0-it-hz]

I think some people might argue that the snare drum is, in fact, a real instrument.

[ashcat_lt]

I downloaded the first one. No offense, but I scanned it before unzipping. Gave me an error (on XP) saying something about the "installion is incorrect". Suggested I might try to reinstall. Since I didn't see anything that looked like it needed installed, I deleted it.

[Skrasms]

I downloaded the first one. No offense, but I scanned it before unzipping. Gave me an error (on XP) saying something about the "installion is incorrect". Suggested I might try to reinstall. Since I didn't see anything that looked like it needed installed, I deleted it.

No offense taken, scanning anything from the internet is a good practice.

What did you use to scan it? I had a friend check it over (in case my system is messed up) and NOD32 reported no problems.

It's just a Max/MSP patch with a bundled runtime, so I'm not sure what would make it raise any flags.

[ashcat_lt]

Used AVGFree. I've got some version of Max/MSP runtime on this machine already. Could that make a difference?

I think it's cool that you bothered to do this, even though I can't see it.

[Skrasms]

Used AVGFree. I've got some version of Max/MSP runtime on this machine already. Could that make a difference?

I think it's cool that you bothered to do this, even though I can't see it.

Do you have the newest runtime for Max 5.0.4? You could probably load the .mxf files into that directly and not even need to worry about the .exe file.

[Skrasms]

I wonder if I should just make a couple quick videos

[47ronin]

On an unrelated note, I see you are in the Purdue/Indiana area...I might be going there for grad school; can you tell me anything about life in Lafayette Indiana?

[tomberdude]

yeah, it sucks there.

HOWEVER, there's a coffee shop near the courthouse that throws underground shows, and the great Sonic Iguana Studios.

-rl

[Skrasms]

On an unrelated note, I see you are in the Purdue/Indiana area...I might be going there for grad school; can you tell me anything about life in Lafayette Indiana?

Hey sorry, I completely overlooked this post!

I found Lafayette to be a little on the boring side, but the schooling was pretty good. There are always shows going on, but I never got into any of the scenes in the area.

I've got a couple friends in grad school there right now, and they're usually too busy to get out much anyway. If you're doing engineering there it is very intense and consuming.