Huh? Reverse phase on ALL mics?

[Farview]

I guess my thought behind it is I want that speaker punching out at me with each kick and hit, and not pulling in when the Bass guitar is pushing out on the downbeats.

Wouldn't it depend on whether the bass player was using a downstroke or an upstroke?

When adjusting phase relationships, the two things have to have some sort of connection to each other. Otherwise it's just random.

 

[mrface2112]

Don't you find that that colapses the sense of space around the drums?

yes, i do. when i align the tracks, i usually pick the snare top or the inside of kick mic as the "reference" and align the rest of them to that. of course, i do it a lot more by ear than sight, b/c moving some mics too much (like the OH or room mics) will collapse the overall sound. so it's almost always an experiment, and in the end some tracks get aligned and some stay where they are.

i also almost always reverse the polarity on my overheads, tom tops, snare top and everything pointing "down", rather than reversing the polarity on the things pointing "up". don't ask me why, it just sounds better that way.


cheers,
wade

 

[tmix]

Wouldn't it depend on whether the bass player was using a downstroke or an upstroke?
.

Not in my experiance.
I have never noticed an upstroke registering any different polarity than a downstroke.

Have you?
To be honest, I can't say I have ever noticed anyway....

 

[TexRoadkill]

When I first heard about this theory it seemed to make sense but years later it seems like bullshit. I don't see how having the drum head go in a different direction then the mic diaphragm is going to suck the mic diaphragm towards the drum. The sound wave is simply generated from a point in the room and the wave will travel the same as any other sound wave.

 

[tmix]

I know.
For me ultimately.... If I like the sound of the drums... I leave it alone.
If I dont like it and suspect it might be a polarity issue (as opposed to sucky sounding drums) I start flipping the polarity and see if that helps.

 

[Farview]

Not in my experiance.
I have never noticed an upstroke registering any different polarity than a downstroke.

Have you?
To be honest, I can't say I have ever noticed anyway....

I've noticed that not every bass note begins on the positive slope. I assumed it was due to alternate picking (plucking).

Like I said before, in order for any two things to have an absolute phase relationship, they have to be somehow connected, (like the top and bottom head of a drum) or at least related (like two mics picking up the same source)

 

[Farview]

When I first heard about this theory it seemed to make sense but years later it seems like bullshit. I don't see how having the drum head go in a different direction then the mic diaphragm is going to suck the mic diaphragm towards the drum. The sound wave is simply generated from a point in the room and the wave will travel the same as any other sound wave.

The diaphragmm of a mic on (for example) a close mic'd snare will follow the same path as the drum head in the same direction of the drum head. A mic that is pointed at the top head will have it's diaphram extended out on the initial stroke of the drum. A mic on the bottom head (at the same distance and angle) will have the diaphragm pushed in at that part of the same stroke.

 

[TexRoadkill]

The diaphragmm of a mic on (for example) a close mic'd snare will follow the same path as the drum head in the same direction of the drum head. A mic that is pointed at the top head will have it's diaphram extended out on the initial stroke of the drum. A mic on the bottom head (at the same distance and angle) will have the diaphragm pushed in at that part of the same stroke.

Like I said. I've heard that before but it doesn't seem to jive with the physics of audio. Do you have any proof of this?

A drum head isn't big enough to create suction and pull the diaphragm forward. The sound wave will still radiate outward just like any other waveform. The only way it would start on a negative swing is simply chance in placement.

 

[Sonixx]

Like I said. I've heard that before but it doesn't seem to jive with the physics of audio. Do you have any proof of this?

A drum head isn't big enough to create suction and pull the diaphragm forward. The sound wave will still radiate outward just like any other waveform. The only way it would start on a negative swing is simply chance in placement.

look at the generated wave forms

put a mic on the top batter head and one on the bottom resonant head, hit the drum and look at the captured waveforms...

 

[Farview]

Like I said. I've heard that before but it doesn't seem to jive with the physics of audio. Do you have any proof of this?

A drum head isn't big enough to create suction and pull the diaphragm forward. The sound wave will still radiate outward just like any other waveform. The only way it would start on a negative swing is simply chance in placement.

What do you think the sound wave is?

When the stick hits the head, it pushes it away from the mic. That pulls air toward the head (away from the mic) as the head vibrates back and forth it pushes and pulls the air around it. That pushing and pulling of air (sound) is what pushes and pulls the diaphragm of the mic.

If the diaphragm wasn't following the movement of the head, we would not be able to recognize the signal coming out of the microphone as a snare hit.

 

[TexRoadkill]

Well I'll be damned. Looking at the close mics it does seem they follow the head. The farther mics don't seem to adhere so closely to that rule.

The only real problem I have with that practice is that while it makes the initial transients positive it would seem to reverse the fundamental tone. In the tracks I was looking at the close mics start with a small negative wave but the larger wave peaks on a positive swing.

 

[TexRoadkill]

Is the goal here to insure that initial transients are pushing the speaker out or in? Or is that we want the fundamental to be pushing the speaker out or in on it's first movement?

 

[tmix]

Good question.
I may be micro managing my tracks by concentrating on the initial transients and not considering the fundamental tone.
I guess with drums (which is what started this whole discussion) the wavform is so short there is not much after the initial big transient.

 

[Farview]

Is the goal here to insure that initial transients are pushing the speaker out or in? Or is that we want the fundamental to be pushing the speaker out or in on it's first movement?

It really doesn't matter whether the initail transient is pushing in or out. It only matters when things are combined. Even then it only matters when related things are combined. (like multiple mics picking up the same drum hit)

 

[Harvey Gerst]

The problem here is that the polarity you choose will determine how the speaker reacts - and that's what counts. Consider this:

You're in the audience and the drummer hits the kick drum. The initial pulse (the leading edge transient) is outgoing from the drum. Now, you interpose your recording chain in such a way that the listener's speakers push out in the same manner. That should maintain the illusion of the original acoustical signal.

The question remains this: Does it matter which way the speaker moves first?

Can you hear a difference? Should a positive voltage on the plus terminal of the speaker system cause the speaker to move out? The older JBL speakers were wired to move in, not out when a positive voltage appeared on the plus terminal. There was no industry standard.

If you consider that the kick drum's initial attack should create a positive pressure on your ears, than the pulse should be positive going (up) on your monitor.

But reversing the polarity of the kick does what? It simply simulates what the drummer is hearing from behind the drum. Is that wrong? I don't think the drummer would think so.

In many tests, people didn't hear any difference in the music, regardless of which way the polarity of the speakers was set up. Try it yourself. Listen to a song, then reverse the polarity of both speakers and listen again. I doubt you'll hear much difference.

What you all are really discussing is whether the music blows or sucks.

I submit that a lot of the music these days does both.

 

[NL5]

What you all are really discussing is whether the music blows or sucks.

I submit that a lot of the music these days does both.

LOL -

 

[TexRoadkill]

Thanks Harvey!

So it would seem that inverting all the mics except for the kick or just inverting the kick would yield the same net result as far as what sounds good.

 

[Harvey Gerst]

It gets too complicated when you start trying to figure out which way you want the attack to come out of the speakers. It hurts my brain just to even start thinking about all those drums and the initial impulse transient of each part of a drum set.

Let's all keep in mind that what we're really talking about is a guy that beats on a lot of shit with wooden sticks. In the end, it depends on whether you wanna hear that from the listener's perspective or the drummer's perspective.

Does it even matter?

 

[Supercreep]

Thanks, Harvey.

 

[Sonixx]

it doesn't matter positive going or negative going...

what does matter is how all this stuff sums before going to the speaker...