Topic: What pattern when off center and close?

[acidjack]

I'm recording in a venue tomorrow with a strange setup, where the SBD area is on the right side wall near one of the stacks.  The place where I can put a bag is just in front of it in a "DJ booth", which is maybe 10ft from the right stack. 

Normally when I am in this place I do a long cable run from a pole in the center of the room, but honestly it is a huge PITA, especially on a Friday when people are all drunk, and I am feeling lazy.  Instead, I think I may try and run a clamp to the table in this "DJ booth".   I will have an SBD feed. 

I'm thinking the best sounding thing from that spot is probably just omnis, but as the 414s can do every pattern, I was also wondering whether wide cards might work.  Obviously the channels will be somewhat unbalanced with the stack being right there, but it seems that'd be the case with the omnis, too....

Any thoughts?  Before anyone asks, onstage is not really much of an option either. For one, it'd mean another long cable run, and two, there isn't a great place to clamp - meaning the mics would have to actually be placed on a little stand on the actual stage.

[jlykos]

If it's your average bar, XY hypercardioid, pointed shading toward the sweet spot.  No perfect solution to this issue, but it's what I do.  You may want to try to slightly compress one channel in the post to even out the signal.

[page]

If it's your average bar, XY hypercardioid, pointed shading toward the sweet spot.  No perfect solution to this issue, but it's what I do.  You may want to try to slightly compress one channel in the post to even out the signal.

Thats basically it. AB at the one good stack is an option I've seen used as well with moderate success. The problem is your left side may be too far off axis to get any real meaningful signal compared to the room reverb/crowd noise.

[Gutbucket]

Tough call, especially without seeing/hearing the postion.

How good is the SBD feed? is it the same as what comes out of the PA?
If the SBD is very good and mostly balanced and all you really need from the mics is room sound, crowd reaction,  liveness, and bottom end, you might try a configuration that reduces pickup of the 10' close stack as much as is practical, otherwise the result is sort of like matrixing a stack tape and a SBD.  If all that rings true, then maybe try something radical: spaced parallel figure-8's, with the whole deal turned 90 degrees so that the side null of both mics points at the near stack.  That way the mics focus on the room and crowd and maximally exclude the close stack.  If you want some stage sound you can turn the array slightly toward the stage, mics still parallel.  That will allow more direct pickup of the far stack and stage sound but help balance to the far off center position.  However, turning much past the 90 degree orientation will let the close stack dominate again pretty quickly. 

This is an unusual application of Tony Faulkner's 'phased array' technique which he thought up as a way to greatly reduce most side wall reflections in a problematic hall.  In this case though, the whole array is turned sideways to reduce the direct sound from the stack appears 90 degrees to the right of the mics, allowing pickup of the room ambient sound and crowd reaction.  I'd use more spacing between the mics than Tony suggests for this though.

[acidjack]

The SBD feed varies... it's a "small club" feed so guitars are sometimes lacking, though the feeds usually at least include every instrument.  But I would need some guitar.

I suppose one advantage is, the mics aren't too hard to change config of on the fly, so...

[Belexes]

I'd only run omnis in a bar on the weekend when really close to one of the mains, otherwise, I like the X/Y suggestions above.

[F.O.Bean]

Hypers PAS

[yltfan]

I have a very similar situation for Thurston Moore and Kurt Vile on Saturday night. SBD is off to the left, but not as close to the stack...probably 40'. Leaning towards hypers, but open to suggestions.

[Gutbucket]

Leaning towards hypers

Probably an appropriate direction to lean.

[page]

Leaning towards hypers

Probably an appropriate direction to lean.

agreed, if you're still far enough back to be getting good sound from the opposite stack, then Bean's recommendation of hypers pionted at each stack is what I'd do. If I'm too close to be getting good sound from that second stack (greater then 35 degrees in my experience), then I give up on the second stack and point both trending toward the one good stack.

[Gutbucket]

If I'm too close to be getting good sound from that second stack (greater then 35 degrees in my experience), then I give up on the second stack and point both trending toward the one good stack.

I think that's very good advice, especially using standard configs.

Let me try and better explain my thinking behind the seemingly off the wall suggestion for parallel figure 8's- The reason I suggested such an unusual configuration is exactly the insight Page notes above.  There are two unusual things about this config which could be advantageous in this situation:

1) Rejection. Because both mics are oriented parallel to each other, without any angle between them, their polar patterns are aligned.  That is important because their composite stereo polar pattern, the combined pattern of both mics together, becomes essentially the same as one mic alone. That's very unusual and doesn't happen with any standard configuration except spaced omnis, in which case the individual mic orientation doesn't really matter.  What makes that especially useful here is that the region of minimal sensitivity (the figure-8 'null', 90 degrees off-axis) of both mics line up with each other, and is located as far 'forward' towards the front of the polar pattern as possible.  That means as a combined stereo pattern, this configuration has the most off-axis rejection to the sides of any other possible stereo configuration by far.

2) Left/Right stereo balance between channels.  Any stereo mic'ing configuration that uses an angle between directional mics exaggerates the level difference between channels when recording from an off-center location, regardless of which direction the stand is pointed.  The larger the angle between mics, and the farther off-center, the bigger the problem.  With the polar patterns parallel aligned, signal level decreases evenly in both channels as sound arrives from off-axis.  That helps significantly by simply not making the problem worse than it already is.  A far less significant benefit is that by pointing the array toward the far side, the close, ‘too loud’ stack is then more off-axis to the mic pair and it’s direct sound is picked up with slightly reduced sensitivity.  That effect is probably insignificant with any pattern other than a figure-8 arranged at a pretty large off-axis angle to the near-side stack.  For a decrease in level of 10dB for the near-side stack (giving it half the perceived loudness it would have if on-axis, to better match the level of the far side stack that is on-axis) the near-side stack would probably need to be about 70-80 degrees off-axis.  That would not be typical in many situations, but does apply to the unique situation described in my first post.

It's those two unique attributes which makes this parallel-8 configuration an exception (possibly the only one?) to "Page's guiding rule of stack proximity".


I think the reason why POS can work better than other typical configurations when far off center and /or further back is that it typically uses less angle between mics than other ‘standard’ configurations, which helps by reducing the near-side louder problem and reducing the overall stereo pattern sensitivity to off-axis room sound. In that way POS is a move towards a spaced, parallel configuration. What would be beneficial for most POS setups is making up for the reduced mic angle by introducing more distance between mics when possible. I think people recording from far back (off-center or not) in situations with compromised acoustics might do well to experiment with parallel spaced directional mics.

Hypers PAS

^^
..with a bit more space between mics than is typical. 

[page]

If I'm too close to be getting good sound from that second stack (greater then 35 degrees in my experience), then I give up on the second stack and point both trending toward the one good stack.

I think that's very good advice, especially using standard configs.

For a decrease in level of 10dB for the near-side stack (giving it half the perceived loudness as the far side stack that is on-axis) the near-side stack would probably need to be about 70-80 degrees off-axis.  That would not be typical in many situations, but does apply to the unique situation described in my first post.

It's those two unique attributes which makes this parallel-8 configuration an exception (possibly the only one?) to "Page's guiding rule of stack proximity".

Correct, I don't have any fig8s anymore and forgot about the 414's ability to do that. In this instance, I'd be tempted to try what you're suggesting, at the very least with one of the mics.

One other idea would be a modified blumlein (or a blumlein MS) where one of the positive lobes is directly pointed at the primary stack and the secondary channel is then "re-positioned" via M/S decoding in post to maximize either signal/noise ratio or stereo soundstage depending on what the sbd provides.

I think the reason why POS can work better than other typical configurations when far off center and /or further back is that it typically uses less angle between mics than other ‘standard’ configurations, which helps by reducing the near-side louder problem and reducing the overall stereo pattern sensitivity to off-axis room sound.

Bingo. I've got some examples where I've been about 25-30 degrees to one stack and almost 50 to the other. Trying to distance mic that other stack is rather futile (IMHO) since you're getting a ton of room reverb. I might as well either point it straight ahead and catch more of the left stack or go for a more AB pattern with the idea of spacing the mics so that they are perpendicular to the primary sound source (in an attempt to keep realtivly it in phase), not the stage as we normally do.

[acidjack]

Well hell, I showed up tonight and this was canceled. So I will have to wait to see if this works. Tomorrow, though- my first blumlein recording!

[Todd R]

I think the reason why POS can work better than other typical configurations when far off center and /or further back is that it typically uses less angle between mics than other ‘standard’ configurations, which helps by reducing the near-side louder problem and reducing the overall stereo pattern sensitivity to off-axis room sound. In that way POS is a move towards a spaced, parallel configuration. What would be beneficial for most POS setups is making up for the reduced mic angle by introducing more distance between mics when possible. I think people recording from far back (off-center or not) in situations with compromised acoustics might do well to experiment with parallel spaced directional mics.

Lots of good info in this short thread.  Thanks esp to Page and Gut for the detailed responses.

I definitely agree with the parallel spaced directional mics.  Makes me wish I had Fig8's available to try Gut's recommendation for this type of set up in small clubs (we've got one here in Denver that is a good candidate for this).  Truthfully, I've never tried parallel spaced directional mics (cards in my experience) in small clubs, only in larger venues.

Back in my earlier days of taping (when I was less lazy apparently), I did this a lot, and it worked out great.  I hadn't been doing it as much, perhaps because instead of having fixed cards only I now have had hypers at my disposal for many years and just went with those.  Using techniques like parallel spaced cardioids when the situation calls for it is one of the reasons I'm in the camp that says if you can only afford to have one pattern of mics, get cards instead of hypers or omnis -- just more versatile.

I was convinced (thankfully) by a friend last fall when recording Phish in a smallish, 20K person arena to run my Milab cards along with my Gefell m210 hypers from the taperssection, which was pretty far back on the floor.  I ran the Gefell m210's DIN and ran the Milabs A-B, parallel spaced about 2 - 2.5 feet apart.  The spaced cards sounded great even far back in an arena this size -- I even liked that source better than my Gefell m210 source.  Actually this was part of the reason I sold the Gefells, for good or bad.

At any rate, off the topic of this thread, but parallel spaced cards can also be a great way to run far back in arenas if you don't have hypers at your disposal (or even if you do).

[acidjack]

What I don't get about the spaced Fig-8 suggestion is what about the rear lobe of the Fig-8?  I get why the side rejection is good if you're off center because the speaker you're closer to won't be as heavy in the mix.  But won't you get strange reflections from the rear lobes, particularly (as in this exact case) where you're off center and also near a wall that is immediately right of the speaker?  What is the advantage of Fig-8 over simply spacing some cards or hypers A-B?

[Gutbucket]

I definitely agree with the parallel spaced directional mics.  Makes me wish I had Fig8's available to try Gut's recommendation for this type of set up in small clubs (we've got one here in Denver that is a good candidate for this).  Truthfully, I've never tried parallel spaced directional mics (cards in my experience) in small clubs, only in larger venues... parallel spaced cards can also be a great way to run far back in arenas if you don't have hypers at your disposal (or even if you do).

FWIW, I haven't used parallel spaced directionals farther back in a small club either, but I think using hypers that way could work especially well as that pattern and config would provide the maximum forward sensitivity and the minimal room pickup possible.  The figure 8 recommendation was to specifically address the far off center, close to one stack location. But generally, when farther back in a small room I'd think spaced hypers or cards would probably work better than 8's because they pickup less from behind.  Exception might be a situation with bad slap echo or nasty reflections from the side walls but relatively benign sound arriving from behind.

[edit- you posted while I was typing.. sounds like we're on the same page, acidjack]