LDCs in omni vs true pressure SDC omnis?

[jnorman]

gonna do a string quartet in a decent small hall soon. right now, all i have is a pair of AT4051s and a pair of AT4050s. i could use an ORTF pair with the 4051s, but i thought omni might be better for this session, so i thought i might use the 4050s set to omni. however, i have also been considering buying a mid-rnage pair of true pressure SDC omnis for this kind of work.

i know that the 4050s set to omni will still have proximity effect, so i will lose some low freq response at mid-distance, whereas true pressure omnis exhibit no proximity effect. how mugh difference would i truly hear between LDCs set to omni vs a pair of true pressure omni? also, what SDC omnis would you recommend? thanks.

[d_fu]

Originally Posted by jnorman

i know that the 4050s set to omni will still have proximity effect, so i will lose some low freq response at mid-distance,

I'd say this conclusion is not correct... Proximity effect means bass goes up when you're close to the mic, but not necessarily that you will lose bass at a distance. Some mics compensate for that by lowering bass response, but not the 4050. I've recorded with AKG 414s in omni and bass was just fine.

True omis will have more ultra-low bass, but with a string quartet, you don't have anything to worry about. I'd try the 4050s in omni or cardioid, whatever works best.

As for good omnis, it's all a question of your budget...

Daniel

[matyas]

I use 414s in omni for classical as well. I've had good luck with it. I've never used 4050s, but from what I understand about them, they should work well also. My best string quartet recording with the 414s, however, had them in Blumlein. I think 4050s do figure-8 - maybe you should consider that as well.

[John Brook]

But why omni? I've done small groups with both 414s and 480s; I've tried omni, wide cardioid, and cardioid. With the 414s, the wide cardioid was very nice. There is no bass to record below 50hz, so you really don't need the omnis, unless you like to pick up A/C noise, traffic rumble, etc.

Unfortunately, AKG doesn't make a wide cardioid for the 480 series (I've contacted Thomas Stubics at AKG several times pleading with them to make one), but I've had good luck with both their omni and standard cardioid.

Last night, I did a string orchestra using the 480/CK61 cardioid, set up in the NOS configuration, and the results were delicious.

IMHO, the 480s are a bit cleaner and clearer than the 414s.

[sonare]

Don't know the specific AKGs mentioned but agree that for a string quartet recording that imaging is important, so a coincident arrangement will likely work best, with an omni pair out and up to allow the sound to bloom.

Personally I do not care for the extreme stereo image from a quartet at a distance that will yield good presence so I use a Jecklin disc for such chamber things. However, subcardioids in ORTF would do the same thing, but you will still want to add an omni pair to the mix.

Anyway, you can make all the plans you want, but if you can't give the players a chance to listen and opine (and also have an option or two for them to hear) you will NOT be a hero to them.

And remember that the most important decision is not the mics or any of the downstream gear (assuming it is at least decent)-- it is the recording venue. The repertoire also determines an appropriate acoustic. Lots of difference between Ives and Haydn.

Rich

[Sonic Lush]

Originally Posted by sonare

... so I use a Jecklin disc for such chamber things.

How and where do you place this Jecklin disc in the hall?

Originally Posted by sonare

...The repertoire also determines an appropriate acoustic. Lots of difference between Ives and Haydn.

Would you speak a little more about how this might affect your choice of mics/techniques?

I would assume most folks with minimal kit (like me) don't have a ton of options for different scenarios..

Thank you,
Slush

[Corran]

A Jecklin disc is placed in between two omnis to block sound coming from one side, giving the omnis more directional characteristics.

As for repertoire, some music you might not want as much of a bass-heavy mix, like Haydn. Therefore the roll-off might work for you.

I hope sonare doesn't mind me answering those questions...feel free to expand.

[sonare]

Bass has nothing to do with any of this-- the issues are imaging and ambience. The use of the Jecklin allows very precise imaging using omnis, which generally have a smoother sound than cardioids. Using the JD allows you to get closer than with cards or subcards (so the presence is there) but the Jecklin tends to compress the apparent width, whereas a close ORTF would tend to exaggerate the L-R. Naturally the omnis are best at also capturing the room.

With a generous acoustic it is possible to do away with the second pair altogether. Listen to Simon Eadon's Grammy-winning recordings of the Takacs Quartet playing Beethoven on Decca. Schoeps MK2S with an M-B jecklin and a TLM170 "sniffer" on the cello-- only up enough so that you are vaguely aware that it is missing when removed.

The quartet disc I did for Naxos was in an awful acoustic and happened before I learned about the Jecklin. Schoeps Mk21 on an ORTF bar kept the imaging under control. In retrospect it was fortunate that I was not tempted by the Jecklin, or I would have had even more of the nasty room in the sound (which was rather dry and hard in the upper mids). Remember that any time you record classical you are also recording the room just as if it were an instrument.

In contrast, there is a German method of recording quartet where each instrument is miked and a very widely-spaced pair is a few feet out to "glue it all together"-- but again, acoustics and taste determine this. This method also takes alot of time to get the intial sound as well as to mix. Tempted with the ability to control ALL relative balances the musicians can go rather nuts with the potential.

For string quartet (or similar chamber ensemble) I try to get a clear and blended sound with precise and stable imaging. The repertoire comes into play with the acoustic. Earlier music can benefit from more ambience, because (with exceptions) that was the prevailing sound in the composer's mind. Later works (20th c for instance) can sound a little muddy, but all this is secondary to what the musicians themselves want. And whether right or wrong, this usually wins out. Use their training and instincts in the choice of venue-- if they LIKE playing in a certain room there is usually a good reason. Or not-- I recall that the quartet I mentioned above LIKED playing in the bad acoustic.

Your best hope of good acoustics are usually found in a church with minimal (ideally NO) carpet, pew cushions, etc. It needs to be large enough so that you can clap your hands and count to at least "two" before the sound dies out. Finally, it must be free of interioir or exterior noise. Very few churches are really good for recording, and some of them have conditions that make it impractical, such as too much noise, high rental fee, not being able to come in after hours, no suitable place for a control room, etc. The original post mentioned "decent small hall" which doesn't sound promising. Hope you have a good reverb program!

Sorry for the long-winded reply-- let us know how it all turns out!

Rich

[videoteque]

Thanks Rich for a deep answer!!!