In Praise of Gearsluts own Michael PM

[bcgood]

Awhile ago Michael was kind enough to send me a cd that he had recorded of the Santa Clara University Music Departments performance of Faure's Requeium, Opus 48. He recorded it with a DAV and an AEA R88. It is an amazing performance and recording. I just wanted to start this thread to give him major props. I love the recording Michael, you rock!

Here's Michael's avatar so you know who I'm talking about.



bcg

P.S. I've included one of the shorter performances from the recording as an mp3 at 256 kbps Constant Bit Rate. Let me know if you want me to take it down Michael.

[boojum]

Very nice. Nice hall, too. It all works very well.

[bcgood]

Originally Posted by boojum

Very nice. Nice hall, too. It all works very well.

Yep, it sure does.

[MichaelPatrick]

bcg, thanks for your overly-generous words.

I try to capture the emotion of music and it's easy when performers deliver it up like this, as they so often do. I'm far less consistent but occasionally do get lucky.

[bcgood]

Don't be shy Michael you deserve some kudos. Seriously this is sonically up there with some of my favorite recordings, I absolutely love it. The music puts me in a contemplative, spiritual mind set of relaxation. It strikes a chord, powerful stuff!

[Remoteness]

Besides the excellent work he does, Michael is a very positive and forward thinking kind of guy.

Kudos to you!

[bcgood]

Hey Michael, I was wondering if you wouldn't mind providing some details as to how you recorded this. Maybe some pics or you could tell us where it was recorded, type of building, where you placed the mic, Blumlein or MS etc.

Thanks in advance!

[MichaelPatrick]

I only recall it was a Blumlein setup in the back of California's Santa Clara Mission Church. It was some time ago and I don't think I could find the notes if I tried. I think I had Shure KSM-141 (omni) outriggers for spaciousness. In any case at least 85% is straight from the AEA R88.

[didier.brest]

Yes it's nice but I wonder whether it would have been better with the mic further because on the most part of the clip, before the brass section income from about 1'30'', there is nothing in the middle of the stereo field. I'm listening on AKG701 headphones.

[MichaelPatrick]

Originally Posted by didier.brest

Yes it's nice but I wonder whether it would have been better with the mic further because on the most part of the clip, before the brass section income from about 1'30'', there is nothing in the middle of the stereo field. I'm listening on AKG701 headphones.

I agree. That can be a drawback of ribbons in Blumlein depending on placement. I'm doing more with them now in M-S for this reason, plus it's more flexible in post production regarding proximity.

[bcgood]

Either way it sounds good to me. Thanks for the info Michael.

[MichaelPatrick]

Originally Posted by didier.brest

Yes it's nice but I wonder whether it would have been better with the mic further because on the most part of the clip, before the brass section income from about 1'30'', there is nothing in the middle of the stereo field. I'm listening on AKG701 headphones.

Your comment refreshed my memory about this program and I now recall there were two instrument ensembles and the choir riser was split, left and right, with a ~12 foot gap between them for the instruments. I think this explains the hole you hear in the choir. Given the setup I believe the mic distance was about right.

Nevertheless, Blumlein does have to be used carefully, as you say, as it can produce a hollow middle without any help from the musicians!

[bcgood]

Originally Posted by MichaelPatrick

Your comment refreshed my memory about this program and I now recall there were two instrument ensembles and the choir riser was split, left and right, with a ~12 foot gap between them for the instruments. I think this explains the hole you hear in the choir. Given the setup I believe the mic distance was about right.

Nevertheless, Blumlein does have to be used carefully, as you say, as it can produce a hollow middle without any help from the musicians!

For all new recording engineers a camera should be a mandatory part of the recording rig. Just a few shots once everything is set up and the musicians are playing for sound check would be a nice way of documenting things.

I was reading an article in last months Tape Op and the professor was saying how a big part of scientific research is just documenting everything that you do so that someone else can repeat it. This could apply to recording engineers as well. Even if that someone else is you!

[MichaelPatrick]

Originally Posted by bcgood

For all new recording engineers a camera should be a mandatory part of the recording rig. Just a few shouts once everything is set up and the musicians are playing for sound check would be a nice way of documenting things.

I was reading an article in last months Tape Op and the professor was saying how a big part of scientific research is just documenting everything that you do so that someone else can repeat it. This could apply to recording engineers as well. Even if that someone else is you!

Great points. I'm only good at documentation I need to get a good mixdown, so when questions like this come up later my memory is often useless. Fortunately, I have a new colleague who's good at documentation. He takes pictures!

[rumleymusic]

That is one smooth sounding mic. I love it.

[David Spearritt]

Originally Posted by MichaelPatrick

Nevertheless, Blumlein does have to be used carefully, as you say, as it can produce a hollow middle without any help from the musicians!

Please explain!

Blumlein reproduces the soundfield accurately across the entire L-R space, the only way to get a hole in the middle is to have no musicians there.

[Audiop]

And if anything one would expect emphasis on the center since the pick up at 90 degrees is about zero and the pick up at 45 degrees is down only a couple of dB.

In plain swedish this means something like +2 to +3dB or so for a centered source compared to a source on axis to one mic and 90 degrees to the other.


/Peter

[Tom McC]

Originally Posted by Audiop

In plain swedish this means something like +2 to +3dB or so for a centered source compared to a source on axis to one mic and 90 degrees to the other.

Yes, centered equidistant sources should theoretically be up 3dB, in Blumlein with ideal mics. This though only applies to the direct arriving sounds, and takes no consideration of hall reverb.

Gerzon (1) pointed out that a major virtue of Blumlein is that it excels at giving a flat, even spread of reverberation energy between the playback speakers. This reverb spread is significantly flatter than what can be achieved with coincident cardioids (flattest at 120 deg.) or MS (flattest with virtual angle 140 deg.). And the reverb spread is very sensitive to angling: if the Blumlein pair is (inadvertently) angled wider than 90 deg., or the cardioid pair wider than 120 deg., then the reverb collapses into a puddle around the speakers, leaving a 'reverb hole in the middle'. (For MS the reverb puddles into the speakers when the virtual angle is decreased, i.e. M increased.)

But presuming Michael's mic angling was exactly 90 deg., the simplest explanation of any perceived hole is that "there were no choristers actually standing in the middle" :-). In such a staging, one must then guard against the mics being too close - to prevent the choristers clustering into the speakers because they were standing outside the Stereo Recording Angle of ca. +/- 75 deg.

1. M. Gerzon "Stabilizing stereo images", Studio Sound, 1974, p 60-64.

[MichaelPatrick]

I appreciate this discussion of Blumlein theory because it's a pattern I like using. I don't know what accounts for some of the "holes" I've heard from Blumlein arrays, I can only guess. Could it be that choirs I work with often array themselves in an arc, putting the center sources at greater distance? Or off-axis response in the center reducing HF details?

In any case, it's comforting to know that the pattern itself is not inherently weak. I've always loved the imaging.

[PlugHead]

Originally Posted by MichaelPatrick

In any case at least 85% is straight from the AEA R88.

Imaging with that mic is remarkable - it's my fave point-and-shoot stereo mic for many sources: piano, kit, choral, chamber orch., horn section, etc., etc.

[Tom McC]

Originally Posted by Tom McC

...because they were standing outside the Stereo Recording Angle of ca. +/- 75 deg..

Oops, obvious typo: the SRA for Blumlein is ca. 75 deg....not +/- 75 deg (= 150 deg.)

[bcgood]

I always thought that a single Schoeps CMC6/MK4 pointing straight down the middle and in front of an R88 would be cool to try. Then use two Radial Phazers to align the R88 signal to taste with the center Schoeps mic.

Almost like a decca tree or MS in that you could adjust to taste the center signal with the ambience that the blumlein captures.