Left side staggered spaced pair - waste of time?

TBman · #1 11-27-2020, 09:17 PM

I was reading last night that a 3:1 distance ratio helped reduce phase issues.

I tried it tonight. One mic was about 11 inches from the fretboard (about the 7th fret) and the other, back at about 28 inches from the 7th fret. (Both mics were AT-2035 large condensers. I may try the same mic setup with the sdc mics that I have.)

I'm using the Avalon, which is a big guitar and rosewood. It can be a little boomy so in the eq I had to do a hi pass. I also used the built-in hipass of the mic which helped a little.

I also recorded the same thing with my Guild D-120, but the Guild records a little tighter and less boomy so I think a closer mic setup would benefit that guitar. I didn't bother to eq and post that track.

Is there anything odd that you hear with this mic setup?

Avalon with 2 at-2035 mics, staggered spaced pair. (fretboard side):

sdelsolray · #2 11-27-2020, 09:50 PM

If you put one mic at 11" and the other at 28" in a straight line of sight from the source (i.e., in a straight line), all frequencies (not just some) generated by your guitar will arrive at the farther mic later than they arrive at the closer mic, causing time delay influenced comb filtering effects (what you call "phase" issues).

That may not be a bad thing. Then again, it may sound weird. How does it sound...to you?

TBman · #3 11-27-2020, 09:59 PM

Quote:

Originally Posted by sdelsolray

If you put one mic at 11" and the other at 28" in a straight line of sight from the source (i.e., in a straight line), all frequencies (not just some) generated by your guitar will arrive at the farther mic later than they arrive at the closer mic, causing time delay influenced comb filtering effects (what you call "phase" issues).

That may not be a bad thing. Then again, it may sound weird. How does it sound...to you?

To my ears it sounds ok which isn't saying a lot. I get the delay though. I'll have to figure out how to delay the closer mic.

rick-slo · #4 11-27-2020, 11:52 PM

Quote:

Originally Posted by TBman

I was reading last night that a 3:1 distance ratio helped reduce phase issues.

As far as recording a guitar that's no and no again. Got so tired of hearing this that I did a little youtube thing:

https://www.youtube.com/watch?v=ryw8v4okgLc

Doug Young · #5 11-28-2020, 01:08 AM

Lots of room sound, mics are too far back for your room acoustics. Sounds a little odd due to the different distances. Be sure to watch Rick's video. the 3-1 rule has nothing to do with stereo micing of a single instrument.

Wrighty · #6 11-28-2020, 03:02 AM

Hi Barry - I don’t understand why you have staggered the mics? The 3:1 ratio that the others have said is irrelevant is the width of the mics apart vs the distance from the instrument as far as I know so the mics are not staggered.

I think that by doing this the sound is always going to be slightly off given the obvious difference in sound travel to mics.

Why not settle on an equally spaced pair about 8-12” from the guitar and play with the vertical levels (Point one up and one down for example) and also the angle of the mics (Parallel to pointing in or out) I am sure you can get a decent sound out of the 2035’s in this way?

Good luck.

Peter

TBman · #7 11-28-2020, 08:13 AM

Ok, got it, thanks everyone.

MikeBmusic · #8 11-28-2020, 09:58 AM

'At the 7th fret' - seems way too far from the guitar body to me.

AcousticDreams · #9 11-28-2020, 10:56 AM

Really looking forward to watching your video Rick-Slo...unfortunately the video does not seem to be coming up.

M19 · #10 11-28-2020, 11:16 AM

Quote:

Originally Posted by Knives&Guitars

Really looking forward to watching your video Rick-Slo...unfortunately the video does not seem to be coming up.

There's no audio. Just a slide to read.

AcousticDreams · #11 11-28-2020, 12:37 PM

Just had to clear out my browser for You tube to come back..
All Righty then...

Thanks Rick-Slow for posting that. Wow, totally clarifies which I am sure that so many(me especially) misunderstood.

And I can see why Drums this would apply as each part of a drum is a different sound source. And for Piano...it is a super large sound source, not like a guitar where most of the sound(but not all) comes from the soundhole.

So now, I think we really need to clarify how to avoid Phasing on acoustic guitar. We need to dive deeply into this subject matter.
To quote one site:
"Phasing can be defined as timing differences from identical (or nearly identical) signals. This can result in a static delay between signals"

It is possible that the popularity of cardiod & Hyper cardiods...is for good reason. As they focus in on different parts of the guitar and thus creating NON identical signals?

Myself, since I am using Wide cardiods are working on other techniques that use angles to avoid Phasing.

But I think this is a topic that can use a lot of clarifying on how to avoid phase issues. I am hoping we can really get into this on a technical side, via this thread or starting a new thread.

rick-slo · #12 11-28-2020, 01:11 PM

Quote:

Originally Posted by Knives&Guitars

Just had to clear out my browser for You tube to come back..
All Righty then...

Thanks Rick-Slow for posting that. Wow, totally clarifies which I am sure that so many(me especially) misunderstood.

And I can see why Drums this would apply as each part of a drum is a different sound source. And for Piano...it is a super large sound source, not like a guitar where most of the sound(but not all) comes from the soundhole.

So now, I think we really need to clarify how to avoid Phasing on acoustic guitar. We need to dive deeply into this subject matter.
To quote one site:
"Phasing can be defined as timing differences from identical (or nearly identical) signals. This can result in a static delay between signals"

It is possible that the popularity of cardiod & Hyper cardiods...is for good reason. As they focus in on different parts of the guitar and thus creating NON identical signals?

Myself, since I am using Wide cardiods are working on other techniques that use angles to avoid Phasing.

But I think this is a topic that can use a lot of clarifying on how to avoid phase issues. I am hoping we can really get into this on a technical side, via this thread or starting a new thread.

Stereo sound (R versus L) is out of phase. That gives it depth, directionality and fullness. That is a good thing. Totally non out of phase would be essentially mono. Plenty of prior threads on this topic in this section of the forum.