phase issues

[bennychico11]

t=d/340

what's the 340 for? just out of curiosity?

 

[ericlingus]

see I can't figure out how to do that. I cant see both waveforms up close together. One or the other is on the screen.

 

[bennychico11]

see I can't figure out how to do that. I cant see both waveforms up close together. One or the other is on the screen.

then do this, is there a way to nudge the wave form by like 10 samples at a time or maybe a little more than that? just nudge the second one slowly back until it sounds the way you want it. or find a reference transient point in the time code on the first track, write that down, and place the same transient on the second track at that time code

 

[Farview]

sorry never noticed that someone else posted this.
phasing does result in attenuation, though. When the out of phase signals (out of time signals) are summed together certain frequencies cancel creating a comb filtering effect.

That isn't the attenuation I'm talking about. You want the mics 3 times farther apart than they are from the source. It helps with phase cancelation because the two mics are not hearing the same thing.

Separating by AT LEAST 3 times the mic-to-source distance creates a level difference of 9dB or more in turn reducing the comb filtering dips to an inaudible 1dB or less....

But if you turn up the distant mic to be as loud as the close mic, you just lost the advantage.

Using the 3:1 with a guitar when micing the neck and body is the same thing as micing the cabinet with a close and far mic, in my mind. In the acoustic guitar example, the neck mic is the far mic in relation to the body. It's still a further distance away from that sound source than the close mic is.

No it isn't, the neck is a different sound source. The sound doesn't come from only one spot on the guitar. The mics will be the same distance from their sources.

 

[ericlingus]

alright I have the audio part editors open for each track, then I just minimized the windows for both and put them under each other. I zoomed inall the way. I see a transient where the second track is further ahead. I just can't seem to figure out how to move the waveform. I know how the move the whole track. But not just the waveform if you know what I mean. The blocks I can move but not the inside of it. If anyone could teach me how to move the waveform back slightly while in the audio part editor i'd be grateful Thanks so far though guys.

 

[Farview]

see I can't figure out how to do that. I cant see both waveforms up close together. One or the other is on the screen.

Your zooming in making things tall, you need to zoom in and make things wide. It's the zoom slider in the lower right hand corner across the bottom.

 

[Zed10R]

I like to mic my amp with two mics. Right now im using one sm57 and one es57(copy of the original). I like to close mic one( about 3 inches away) and another one about a foot away. I put one on axix(the closer miked one) and one off axis. But I can't get rid of the phasing. I tried changing the mics around a little but it still doesn't work. The only way to get rid of it is if I both put them the same distance from the amp. But I dont want that sound. I play black metal and prefer a little more distance on my guitars. I have a mesa boogie F50,the two mics I mentioned going into a firebox. Cubase LE is my recording software with a pretty high end computer.

OK....you may not like this, but I strongly suggest that you record your tracks with 1 mic in position "A", then re-record all your tracls with one mic in posotion "B", and blend to tase. It takes more effort and you must play your parts TIGHT, but it WILL sound better. I promise. It's all about the music, right?

 

[ericlingus]

well I figured out how to do that but I realize the first wave form(mic number1) is streched out a little more than the second. What do I do in this case?

 

[ericlingus]

I really would rather use two mics at the same time. Once I get the phase issues dealt with I will have no problems with it.

 

[ericlingus]

farview thank you! This solves the problem. I have to eye it though. Is that what you have to do? I just see two transients and line em up the best I can with my eyes.

 

[Farview]

Yup. When you zoom all the way in, your entire screen is 1/1000th of a second. You can eyball it at that resolution.

 

[ericlingus]

Now this is being a bitch. i have to move the second one back but can't do that because they are both starting from the beginning. It won't let me move the second one any further. I can only move forwards. In that case i'd have to move the first one forwards to match the second. But then i'd have to move every track to match the first one which will be a bitch!

 

[Farview]

You need to grab the left edge of the clip and pull it right. (make it smaller) so you can move the second mic in time with the first.

 

[ericlingus]

okay NOW I get it! thank you very much Mr. Farview for sticking with me till the end.

 

[RAMI]

I have a question about lining up the tracks. Doesn't that defeat the purpose of having one further away, especially if it's 2 of pretty much the same mic. What's the difference between going through the trouble of micing one far and one close then lining them up...or...Just placing them equal distance from the source.

 

[Zed10R]

I have a question about lining up the tracks. Doesn't that defeat the purpose of having one further away, especially if it's 2 of pretty much the same mic. What's the difference between going through the trouble of micing one far and one close then lining them up...or...Just placing them equal distance from the source.

He's being lazy. That's all there is to it. I think. Is that all there is to it lingus?

 

[Farview]

The cabinet doesn't sound the same a few feet away as it does up close. I still prefer the close mic'd and doubled sound better.

If I use two mics, it's normally a 57 and a 421.

The lining up tracks thing will help when you are recording bass by micing and cab and running a DI.

 

[cpl_crud]

what's the 340 for? just out of curiosity?

speed of sound in air in standard units (ms^-1)
I come from foreign lands that have a much quicker uptake of international standard units :Þ
You can alter that to the speed of sound in feet/inches if you so desire- that much I leave up to you

And yeah, you've got to remember you've got a lot of different things happening with the sound at 10 cm and 30 cm. In fact, with your standard 8" cone (I'm meeting you half-way here, hippies) you're still going to be in the near feild of the cone with the first mic, which is going to have some interesting effects, not to mention the differences in the room between two points.
Recording at different points and then delaying is going to create a different sound than coincident micing.
Rembering that we're only talking a difference of about 1/1000 th of a second, there's not that much "audible" differnce in the timing of the sounds, it's simply to try to negate any phasing issues (Fun Fact: a group of humans can "synchronise" to roughly 1/100 th of a second when assisted by a steady beat, and, conversely, a change in tempo of the same order can be detected).

 

[ericlingus]

sounds different to me still doing it this way. As far as using the same mic, that'll change in a few days when I get a E609s. Right now i'm still experimenting. How is it being lazy using two mics? I still do multiple performances.

 

[Zed10R]

sounds different to me still doing it this way. As far as using the same mic, that'll change in a few days when I get a E609s. Right now i'm still experimenting. How is it being lazy using two mics? I still do multiple performances.

In my opinion, the end result will be better if you track one mic at a time, each in it's ideal location, and mix to taste. 4 tracks of guitar this way will sound better than 2 tracks the way you desribed.....but 4 tracks your way could sound better than what I just said....if that's closer to what you are doing...I don't know.....so my apologies for the lazy comment....