M/S question...

[Phildo]

Here's something that's just occurred to me, two bottles of Chardonnay down the line:

Could I achieve M/S recording with 3 cardioid mics?

Surely if I position two cardioids at 180 degrees - i.e. to give me a figure-8 pattern - and another as I would normally in an M/S setup, record them to 3 tracks, pan the "edge" cardioids and flip the phase of one of them, would that not result in essentially an M/S arangement?

Just a thought...

 

[hairylarry]

not quite

Hi,

When you use a figure eight mic you get one channel with both sides of the mic, front and back. So take your two cardiods and mix them together into a single mono signal. Then phase shift that signal to another track.

Thinking high impedance cardiods you could Y the opposing mics together into one signal and then Y them back out with one of the outputs reversed.

So the two channels you get from the figure eight contain both sides of the pattern. Just one of them is 180 degrees out of phase.

This is why they zero out when you match volume levels.

The third mic, pointing at the source, can be cardiod to hypercardiod. Even an omni works for the third mic.

It does work with three mics. I have done it. I used a little mixer to mix the opposing mics together and then took two outputs of the same mono signal and phase reversed one of them with my DMP-2. Say tracks 1 and 2.

Record the center channel mic into track 3 at the same time.

When mixing leave three down and listen to 1 and 2 mono. By themselves, not mixed together. They should both be full and clear and sound identical.

Bring them both up to about the same volume level and adjust them until you can't hear them. Still mono. Because 2 is 180 out of phase with 1 this really happens. The purpose of this is to get them both at the exact same level so your stereo signal will be centered.

Pan 1 left and 2 right. Bring up the center channel. You should have full rich stereo. Adjust the center channel for sound and stereo image. I listen through a JVC with a mono button. When I push the mono button it still sounds good. Just not stereo.

I did get a figure eight mic so I am interested in trying that too. Next Month.

Thanks,

Hairy Larry

 

[dgatwood]

Here's something that's just occurred to me, two bottles of Chardonnay down the line:

Could I achieve M/S recording with 3 cardioid mics?

Surely if I position two cardioids at 180 degrees - i.e. to give me a figure-8 pattern - and another as I would normally in an M/S setup, record them to 3 tracks, pan the "edge" cardioids and flip the phase of one of them, would that not result in essentially an M/S arangement?

Just a thought...

Sounds familiar.

https://homerecording.com/bbs/showthread.php?t=144396&highlight=mid-side+cardioid

 

[ofajen]

It does work with three mics. I have done it. I used a little mixer to mix the opposing mics together and then took two outputs of the same mono signal and phase reversed one of them with my DMP-2. Say tracks 1 and 2.

There is one small but important step missing (or at least not mentioned) here. If you take opposed cardioids and mix them, the result is omnidirectional, i.e. with no angular info. This is, in fact, exactly how multi-pattern mikes produce the omni setting. If on the other hand, you mix the two opposed cardioid signals together, one with polarity reversed, you will get a figure-8 response. This is, in fact, how multi-pattern mikes do figure-8.

So, you need to add that one step into your procedure: mix the two opposed cardioids together, but with one reversed in polarity, to produce the figure-8 pattern. Then you take the mixed output of the opposed cardioids and add it (+S) to the left output and add a polarity reversed version (-S) to the right output, as you mentioned, while the middle signal (M) goes equally to left and right.

I hope that clears things up.

Otto

 

[hairylarry]

I get it

Hi,

Thanks for the clarification. On a ribbon mic the back side is physically 180 degrees out of phase with the front side.

To simulate this with two cardiods mix them to mono with one of them phase reversed.

Then split that signal to two tracks one phase reversed, one not.

Record the center channel at the same time.

Mix as above.

One more thing to watch for. Some mics get noisy in the presence of other mics. Be sure to listen for noise if you are placing your mics close to each other.

Thanks,

Hairy Larry

 

[slidey]

hmmm

I'm..........

well

shucks that was educational

I thought I was achieving M/S with 2 mics

well, well you live & learn huh

 

[Farview]

hmmm

I'm..........

well

shucks that was educational

I thought I was achieving M/S with 2 mics

well, well you live & learn huh

YOu are supposed to be using two mics. A figure-8 and a cardioid. This thread is about getting around not having a figure-8.

 

[slidey]

YOu are supposed to be using two mics. A figure-8 and a cardioid. This thread is about getting around not having a figure-8.

boing boing boing

& things get ever clearer

 

[ofajen]

YOu are supposed to be using two mics. A figure-8 and a cardioid. This thread is about getting around not having a figure-8.

Precisely. The thread started with a question about simulating a normal M/S two mike setup with three mikes, where two cardioids are used to simulate the figure-8. M/S works best with a really good figure-8 ribbon mike for the S position.

Otto

 

[slidey]

WIKID

I was missing vital info up till now & look forward to recording M/S properly albeit I don't have a fig.8 mic but there's other ways as have been discussed earlier