Topic: BLUE mics for taping/large diaphragm condensers in general

[twoheadedboy]

I have a home studio set up with a BLUE Baby Bottle and Robbie pre-amp. I am absolutely thrilled with the quality of both. Looking at the specs, this mic can take up to 133dB. What I'm wondering is if I was to duplicate this setup and run them as a stereo pair, how would that work with taping live concerts, say with an ORTF or XY set up? Would this be good or is there some "gotcha" that I'm not considering?

[notlance]

XY is kinda hard to do with LDC mics (especially with shock mounts) but ORTF, DIN, NOS, etc should work just fine.  The polar pattern looks more like a hypercardioid, so technically you would not be using ORTF or DIN or the other near coincident setups since they call for a cardioid pattern.  However, your recordings will probably sound fine, perhaps with a few adjustments to the microphone angle.

[hummat]

I've been using Bluebirds for the past 7-8 months and really like'em.  I am not running from the section though.  I am on-stage, ORTF, snaked back to the booth where my DR-680 is.  In addition, for the other 6 channels, I am either taking instruments directly and/or subgroups from the board. 

EDIT:  Here's a show with the Bluebirds in a more standard SBD/mic matrix usage:
http://www.archive.org/details/jsdn2010-03-20

-jay

[Brian Skalinder]

XY is kinda hard to do with LDC mics (especially with shock mounts)

Nah, it's easy.  Just gotta run 'em vertically:  http://taperssection.com/index.php?topic=51606.msg1068595#msg1068595 

[notlance]

Yes, I thought of vertical XY right after I hit "Post", but I was sure someone would point out my oversight.  This also indicates how often I run XY.

[DSatz]

In ordinary studio recording the majority of sound energy reaching a microphone arrives more or less on-axis, and the off-axis sound quality of the microphone mainly affects how the room sound is picked up, but not the direct sound.

With the usual types of two-microphone stereo recording setups used by tapers, however, the microphones are aimed away from the center of the direct sound sources at some significant angle. Because of that fact and the pickup distances involved--which cause a rather large proportion of the sound to be reflected off of walls, ceiling and floor before reaching the microphones--the majority of the sound energy that the microphones receive is reaching them from significantly off-axis angles. Approximately half the total sound energy at typical "taper" distances is arriving from effectively random angles all around the microphones; in many cases it is even more than half. So in stereo taping, a microphone's off-axis response takes on a considerably greater importance than it usually has in the studio.

That fact changes everything, since basic acoustical physics dictates that the off-axis frequency response of a large microphone can never be very much like its 0-degree frequency response unless it is a pure dipole (= a figure-8) or very nearly so. The typical large cardioid, for example, is only really a cardioid in the midrange, with a narrow pickup pattern at high frequencies and an increasingly broad pattern at low frequencies.

Two-microphone stereo methods with closely-spaced or coincident microphones rely on having the same directional pattern throughout the audio frequency range--which translates into a constant frequency response across a wide range of incidence angles. And large microphones in general do not have that characteristic, particularly dual-diaphragm cardioid or switchable-pattern microphones which are the most common type in studios.

With small single-diaphragm condensers these problems don't go away entirely, but they are are lessened considerably. For this reason among others (sight lines, ease of mounting), small microphones are generally favored for two-microphone stereo recording.

--best regards

[Shadow_7]

One issue might be bulk and weight.  That's a lot of weight to be flying high.  Not a problem with a good stand, but with a bad one...   BOOM!.  I've been toying with the ideal of 2x HM7u's myself.  But not in the market just yet. 

The 133dB SPL might be problematic.  Depending on the group and your location (mic location) to it.  Some mics change character as they approach their max SPL.  And that's kind of a low one for live events.  Not that any one source will be pumping 140dB.  But the combination of several with door slams, mic accidents and applause, you can peak that level more than you'd like.  Depends on the group and the venue though.

The other issue is that it's harder to protect large profile mics from the wind.  Not impossible, just harder.

[twoheadedboy]

This is all great info. Thanks guys.

[SmokinJoe]

I think the best answer is "try it and see if you like it".  Even if it's only one channel of that and one channel of something else.  That's why we have "opening acts"... so you can try stuff.

It really comes down to what YOU like.  I run LD's most of the time, generally cards/DIN, but other patterns on occasion.  I have found from recording at the same places week after week that particular mics (ADK-TLs and AKG414's) are pleasing to my ears, more so that other SD's I have tried, and/or other SDs that are set up next to me.  This is primarily at clubs where I'm 5-20 feet from stage.   In my case I'm close enough to the stacks that I'm getting stack energy, and some on-stage energy, but probably not too much radiating off the side and back walls.  I don't mind the LDs when I'm outdoors too (where I guess there isn't much reflective energy), but if I'm at a big arena I would take the SD's.

DSatz is correct in saying that most LDs generally do not have great off-axis response.   But this isn't always a bad thing.   In particular one venue (The Stone Church in New Hampshire) we tend to clamp to a beam about 3' over the heads of chatty wookies.  I had Earthworks SR-77's which have exceptionally smooth off axis response, which resulted in very crisp and clear chatter.  I didn't particularly like that.  I'd rather have colored chatter which is slightly easier to ignore.