Topic: Side mic from two Core Sound Cardioid Stealthy mics?

[TheJez]

Hi everyone,
Just for fun & experimenting, I consider trying to create a side mic by putting my two Core Sound Cardioid Stealthy mics back-to-back. The mics are joined to a 3.5mm stereo mini-jack, so common ground at the sleeve, left=tip, right=ring (or vice versa, don't know for sure).
My mid mic will be an SP-CMC-4U mic with XLR connector.
Unfortunately I don't have a multitrack recorder. I do have a Tascam FR-AV2 (2x XLR/TRS in, mini-jack in) and an Edirol R09-HR (mini-jack in).
My plan is to record to Core Sounds into the Edirol, then afterwards in DAW, invert the phase of one channel and sum them to a single side channel. The mid channel would be recorded by the Tascam. Then, afterwards, sync the mid and side and do the m/s stuff to play with the stereo image.
Especially needing two recorders and having to sync afterwards isn't very convenient for my intended setup. Ideally I'd somehow want to connect the two Core Sound's to a single input of the Tascam. Would it be possible to connect left and right to pin 1 & 2 of an XLR connector to establish this? Or am I missing something then (e.g. the phase inversion)? If so, how could this be fixed? Any thoughts and suggestions would be appreciated!
I can't/don't want to spend much money on this experiment, so buying a multitrack recorder or getting a true figure-8 mic for this is not an option, but buying a female mini-jack and an XLR connector and do some soldering is not a problem, as long as I don't have to cut-up the existing wiring of the Core Sound's. I'd like to achieve the best possible results with my far from ideal set of equipment at hand.
Thanks!

[grawk]

assuming you can power them via an external bb, you could make a cable that goes minijack -> xlr and combine the 2 mics into 1 channel.  pin 1 = ground, pin 2 = left pin 3 = right.  It still won't be a figure 8, but it might be interesting to try.

[TheJez]

assuming you can power them via an external bb, you could make a cable that goes minijack -> xlr and combine the 2 mics into 1 channel.  pin 1 = ground, pin 2 = left pin 3 = right.  It still won't be a figure 8, but it might be interesting to try.

Thanks grawk for responding/confirming.
Yes, I have bb for the core sound mics! I was thinking the same wiring but mixed up the pin numbers and was in doubt about the correct phase. Now I'm thinking of it: Let's say left mic is pointing left, mic right pointing right. If a positive wave arrives from left to right, it will generate a positive voltage on pin 2, and a -more or less- equally negative voltage on pin 3 (or vice versa). The recorder records the delta between the two and Bob's your uncle :-)
Sounds good, I will give it a try when my SP-CMC-4U arrives and I get an XLR connector...

[grawk]

The side channel definitely won’t sound like a figure 8 but it may process down close enough.

Back in the day when I was first playing with midside I used an at stereo mic as a figure 8

[TheJez]

The side channel definitely won’t sound like a figure 8 but it may process down close enough.

Back in the day when I was first playing with midside I used an at stereo mic as a figure 8

Yeah, I know it won't be perfect... I thought it may be an interesting experiment to try once I have my new SP mics...

[grawk]

I will warn you that the logical end to the midside journey is a schoeps double mid side rig

[TheJez]

I will warn you that the logical end to the midside journey is a schoeps double mid side rig

Haha, I probably can’t afford that! I don’t even dare to check it out… 

[robgronotte]

Why would you want to pick up more side noise?  The point of having cardioid mics is to not record much of that.

[grawk]

Why would you want to pick up more side noise?  The point of having cardioid mics is to not record much of that.

If this is a serious question, there's a microphone technique called "Mid-Side" which is mathematically equivalent to XY, but instead of 2 mics each 45 degrees off the center axis, one of the mics is on the center axis, and the other is a figure 8 microphone that captures the "side", + on the left and - on the right.  You combine the side signal with the mid to get the left channel, and the inverse of the side channel with the mid to get the right channel, which you can then control in post to vary the perceived width.   There's a LOT of writing about this technique.

[robgronotte]

Huh, seems like a lot of complication to make for a worse recording, at least for what I want in a live recording. I try to get the annoying crowd on the sides of me completely out of my recordings.

[TheJez]

Huh, seems like a lot of complication to make for a worse recording, at least for what I want in a live recording. I try to get the annoying crowd on the sides of me completely out of my recordings.

(I'm not an expert on this, so I may be talking nonsense, but I'll give it a try:)
Yes, so do I... However, somewhere in the past I was unfortunately forced to record some shows with a single (cardioid) mic. Although I managed to get very decent recordings without much of the annoying crowd, the recordings sounded rather dull. Although I really hate people near me discussing the latest office gossips during a show (and they really have to shout to make themselves heard), the mono-recording made me appreciate the sense of spaciousness of a two-mic recording. At a typical rock show the sound coming out of the PA's left and right is usually about the same. There, the sense of spaciousness is provided by the reverb of the venue, and yes, by the people making noise (hopefully not too much relative to the music you want to record) around you. With a classic X/Y setup, the balance between the sound coming from the front and the sound left/right of you is fixed at recording time. When doing a mid/side recording, you can change this balance in post production.
I have no immediate intention to start doing M/S recording during shows that I matter much about, but I am a bit intrigued by this recording technique and would like to experiment with it without directly spending much on the equipment. A figure-8 mic as side-mic is what would be needed to do this properly, but I don't have one laying around. However, putting two cardioid mics back-to-back construct a more or less similar signal.

[grawk]

Huh, seems like a lot of complication to make for a worse recording, at least for what I want in a live recording. I try to get the annoying crowd on the sides of me completely out of my recordings.

Then you shouldn’t try it.

[robgronotte]

Huh, seems like a lot of complication to make for a worse recording, at least for what I want in a live recording. I try to get the annoying crowd on the sides of me completely out of my recordings.

(I'm not an expert on this, so I may be talking nonsense, but I'll give it a try:)
Yes, so do I... However, somewhere in the past I was unfortunately forced to record some shows with a single (cardioid) mic. Although I managed to get very decent recordings without much of the annoying crowd, the recordings sounded rather dull. Although I really hate people near me discussing the latest office gossips during a show (and they really have to shout to make themselves heard), the mono-recording made me appreciate the sense of spaciousness of a two-mic recording. At a typical rock show the sound coming out of the PA's left and right is usually about the same. There, the sense of spaciousness is provided by the reverb of the venue, and yes, by the people making noise (hopefully not too much relative to the music you want to record) around you. With a classic X/Y setup, the balance between the sound coming from the front and the sound left/right of you is fixed at recording time. When doing a mid/side recording, you can change this balance in post production.
I have no immediate intention to start doing M/S recording during shows that I matter much about, but I am a bit intrigued by this recording technique and would like to experiment with it without directly spending much on the equipment. A figure-8 mic as side-mic is what would be needed to do this properly, but I don't have one laying around. However, putting two cardioid mics back-to-back construct a more or less similar signal.

Yeah, it might be interesting to try, but if you really are wanting to recreate the ambiance of the room, wouldn't it be easier just to use two binaural mics?

I agree that mono recordings generally sound a bit dull, and I like there to be some significant difference in the two channels.
I'm a fan of the sound of the Core Sound cardioids and have used them for years. But I don't generally point them both straight forward. I'm typically pretty close to the front of the room, not dead center, but a bit to one side or the other, roughly equidistant of between the band and the PA on that side. Then I try to point one mic at the band and the other at the PA.
That way I get a somewhat different mix in each channel, with the main difference being that more vocals are in the channel with the mic pointing at the PA.  Sometimes there is a significant volume difference between the two channels, but that's really easy to balance in any music editing software.

I know my method isn't common, as I've never heard of anyone else doing this, but my recordings generally turn out great (to my ears anyway), and I've received lots of compliments on my recordings over the years.

If you're interested in hearing any of them, there are a few on archive.org, some on TTD, and lots on DIME. All made with CSC or other small cardioid mics. If you need help to find any, just send me a message.

[aaronji]

At a typical rock show the sound coming out of the PA's left and right is usually about the same.

Almost all of the shows I go to are mixed in stereo.

In my mind, one of the conveniences of MS is that it is an easy low-profile set-up.

[goodcooker]

Your biggest challenge is going to be how to mount the mics so that the side mics are oriented exactly 180 degrees from each other as close as possible and that the mid mic is 90 degrees perpendicular to it.

This is one of those scenarios (unlike other stereo arrangements that are a little more forgiving of a few degrees of inconsistency) where if the mics move AT ALL it will drastically change the sound of the results.

The other challenge you face is not having enough clock synced channels. Using two recorders from different brands and decades is probably not going to work out very well but, hey, stranger things have happened.

Give it a shot. Experimentation is fun. Like many, I learn by doing.