Pulling Then Pushing

[Nu-tra]

I've been having polarity/phase problems in my studio... I have been going through my drum tracks and noticed at first that my snare top needed flipping. I later read that oktava's are pin 3 hot instead of pin 2. So I flipped the polarity on the overheads and they sounded better on their own then I noticed the snare top was in phase but my toms needed flipping and it sounded so much better and focused. Is this normal? Can anyone confirm if Oktavas are this way? I am going to go through all my cables tomorrow after NAMM. I also noticed my kick drum waveforms visually push while and my snare top and toms and overheads pull on their initial hits.

[Nu-tra]

Here is the snare top

[Nu-tra]

Well Michael from Oktavamod.com was cool enough to verify that Oktava's are pin 3 hot. This explains a lot.

[dbbubba]

I just did a live recording where I mixed API, Sphere and the mic pres in a Midas console.
I built the cables that interfaced the APIs and Spheres to my converters and I thought hard about all of this while soldering away last week.

I am listening to the material we recorded starting today.

While I was recording I noticed that flipping the under snare mic didn't produce the result I expected.
The snare top and bottom mics were both SM57s, but the top was in an API and the bottom mic's pre was the Midas.

Now you have me worrying about THIS!

[Nu-tra]

Haha! Well I narrowed down some of this... Confirming my oktavas are pin 3 hot helps. Looking at the photos shouldn't the sound waves rise first then drop before you decide to invert them?

[wrekdahouse]

do you mean all the oktavas, or one model in special ?


interesting

[Nu-tra]

He said that Oktavas are wired pin 3 hot.

I would assume all of them. This is the first time I used them as overheads and it made me start to question why I was having problems with polarity.

[juniorhifikit]

this is why the good lord gave us ears and the polarity button on the console...

[Nu-tra]

So true. I am learning a lot about this since I have to investigate my problem. I dont run a commercial studio. I have adequate equipment and I like to record. I haven't recorded any of my projects yet since I recently finished building the room so I am still trying to get the kinks out. Should the snare and tom waveform be pulling like that?

[rhythminmind]

You have to check phase of everything thats not a isolated single source. There isn't a "proper phase" Theres only the phase relative to another source. The phase of miced audio is determined not only by the polarity of the output but more importantly the time the audio hits the mic. example: moving your overheads even a foot will change the phase relationship of the signal. Phase flipping is common place. Making sure gear polarity the same dosen't stop the need.

[juniorhifikit]

Originally Posted by Nu-tra

So true. I am learning a lot about this since I have to investigate my problem. I dont run a commercial studio. I have adequate equipment and I like to record. I haven't recorded any of my projects yet since I recently finished building the room so I am still trying to get the kinks out. Should the snare and tom waveform be pulling like that?

sometimes the first "lump" you see in the waveform isn't what we perceive as the transient. Again, try not to "see" phase, just listen, in mono even.

[MarkRB]

I read someone say on here a while back about transient sources sounding different when you reverse the polarity.
I was very sceptical but tried it on a recorded close mic'd kick drum and was really amazed to hear a difference. It was subtle but there was a small but noticeable loss of sub energy when I reversed the phase.
Can anyone verify this?
It could be I was just hearing some deficiency in the desks flip switch so I'd be interested if anyone has noticed anything similar.

[rhythminmind]

Originally Posted by MarkRB

I read someone say on here a while back about transient sources sounding different when you reverse the polarity.
I was very sceptical but tried it on a recorded close mic'd kick drum and was really amazed to hear a difference. It was subtle but there was a small but noticeable loss of sub energy when I reversed the phase.
Can anyone verify this?
It could be I was just hearing some deficiency in the desks flip switch so I'd be interested if anyone has noticed anything similar.

Yeah you should keep the attack transient on the positive.

[kafka]

Originally Posted by Nu-tra

Should the snare and tom waveform be pulling like that?

Originally Posted by rhythminmind

There isn't a "proper phase" Theres only the phase relative to another source.

What this guy ^^^ said. Out or in first - it could be either. It could be different on every note. The only important thing is what it is compared to what you're mixing it with.

[stuntbutt]

Originally Posted by MarkRB

I read someone say on here a while back about transient sources sounding different when you reverse the polarity.
I was very sceptical but tried it on a recorded close mic'd kick drum and was really amazed to hear a difference. It was subtle but there was a small but noticeable loss of sub energy when I reversed the phase.
Can anyone verify this?
It could be I was just hearing some deficiency in the desks flip switch so I'd be interested if anyone has noticed anything similar.

I've found that trying to hear absolute phase on speakers in a room can fool you. Test again with phones.

[dbbubba]

They way to check is to get a "phase checker" that puts out an impulse with one module that plug in at the beginning of your signal chain.
There is receiving device that looks at the impulse after it travels through your signal path and tells you if the phase is reversed.
They are not that expensive and Rolls Music makes a rather in-expensive ($150??) unit.

You actually DO want the speaker to move in an outward direction when a positive pulse is fed to it.
It is especially important when you deal with large diaphragm speakers like 18"s in a large sound system.
You want the initial impact of things like kick drums to push the speaker outward not only because it causes the initial wavefront of the sound to travel outward, but because you don't want the positive going and often stronger peaks to cause the voice coil to bottom out.

THERE IS A RIGHT WAY AND A WRONG WAY TO PHASE SPEAKERS!
I don't mean having the left and right speakers in phase with each other either.

In live situations we often use phased array subs to create a cardioid pattern of dispersion to focus and control the low end.
This set up requires very close attention to phase.
Also, many live system speakers have VERY specific phase settings.
This is especially true of newer design sub enclosures.

There really is no relative phase between mics, but you do need a starting point and you might as well have the wavefront moving in the proper direction.

It IS hard to look at waveforms and know what you are seeing unless you are really trained and really experienced at interpreting what you see.
I don't think you could really determine the phase of OHs that easily, but a kick drum is another matter.

Using your ears is important as the final test, but you would be wise to work hard to see that the positive pin is wired to the positive lead and phase stays consistent through any sound system.

[Idiophonic]

Nutra,

To respond to the bit about the kick, toms, and snare...

I also noticed my kick drum waveforms visually push while and my snare top and toms and overheads pull on their initial hits.

This is to be expected based on the position of the mics and the way the drums are hit. The head of the kick drum moves toward the diaphragm of the kick mic when struck (assuming you are micing the inside or front of the kick). Conversely, the stick hit on the snare and toms initially pushes the head down, away from the top mics and OH mics, resulting in air moving away from the mics' diaphragms...

As far as nudging and flipping, trust your ears. I generally try to use the OH mics as a reference and get the close mics to be in agreement with these.

[dbbubba]

How did guys like me do this before we could see the waveform?

My advice? Don't confuse yourself with too much information.
Don't look at the waveforms!
Listen to the sound coming from your monitors.
All the information you ever need is right there.

[Nu-tra]

Aha! This is th answer I was looking for.

Thanks to everyone! I am still gonna make sure my wiring is good. I tell you those damn oktavas kinda surprised me. I figured people would spread the word that pin 3 is hot on their microphones. There's reason I asked is because I noticed Peeder posted about pin 3 a year ago. I decided to confirm it. HEY EVERYONE OKTAVAS ARE PIN 3 HOT!!!!

Originally Posted by Idiophonic

Nutra,

To respond to the bit about the kick, toms, and snare...



This is to be expected based on the position of the mics and the way the drums are hit. The head of the kick drum moves toward the diaphragm of the kick mic when struck (assuming you are micing the inside or front of the kick). Conversely, the stick hit on the snare and toms initially pushes the head down, away from the top mics and OH mics, resulting in air moving away from the mics' diaphragms...

As far as nudging and flipping, trust your ears. I generally try to use the OH mics as a reference and get the close mics to be in agreement with these.

[DesertDawg]

Idi and Danny are BOTH right... on one hand your kick is going to exert a different transient waveform than your toms or snare because you (usually, anyway) have the kick mic accepting the transient from the head on the positive cycle, while your toms & snare are (usually, again) accepting the transient either on the negative cycle or some kind of combination of the positive & negative, depending on how fast your chosen mics & preamps are able to react. At the same time, use your ears, not your eyes... what sounds more "right" to you? The kit is both many instruments unto themselves, and one aggregate instrument at the same time. Do you really want to phase-flip & nudge tracks, and all kinds of shit like that? Or does it sound fine just the way you've mic'ed it, assuming you've done a good job there?

[Waltz Mastering]

For me the best way to check phase is to monitor in mono. If the low end disappears and the sounds gets thinner, its out of phase. 101

TW

[AnthonyRochester]

oh good, it doesn't surprise me that oktavas are pin 3 hot, I am often flipping the phase on them when i use them as overheads..

[A LaMere]

well, I for one was certainly surprised when using them as drum overheads recently...

I'll be honest... it bugs me.

Among the many things that bugs me about the Oktava's.... they're freakin' quirky, I gotta give 'em that I guess.

For anyone reading this... read:
You must flip the phase of the Oktava's when using them as drum overheads due to the fact that they are wired pin 3 hot.

It took me about an hour of screwing around, re-positioning before finally drinking a cup of coffee, waking up a bit and flipping phase at the pre...