johnthemiracle said:
actually i have yet to hear an ortf recording with a hole in the middle. said holes are unfortunately far easier to achieve with ab micing. far easier.
and why should the two cardoids be out of phase even with a solo instrument? i don't think so. they're maybe not 100 percent in phase, since they're angled but certainly not completely, or mainly out of phase.
john, john, john...
I think you know enough about recording to be dangerous, but the simple fact is you are not providing proof for your argument, just "I have never heard..." There's a reason you've never heard an ORTF recording with a hole in the middle. 1: No reputable recording company records classical music using an ORTF mic position. 2: Record labels very rarely tell you what kind of set-up they are using, so how would you know what kind of mic set-up they are using.
johnthemiracle said:
well...greater. 1.5 meters or more. (especially for large sound sources such as orchestras). therefore the a/b mics for orchestra recording usually hang from ropes from the ceiling or balconees...i've neither heard nor experienced good things from recordings with small ab.
1.5 meters??? Wow, no wonder you are getting a hole in the sound with A/B. 20-30 centimeters for your main pair should be sufficient. If you haven't heard any good recordings from A-B small A-B then you haven't listened to a single Telarc recording. Check out their info about mic'ing here:
http://www.telarc.com/about/history3.asp?mscssid=H0P5LR4MR1M09L5CVH907VFEF94R7T4E
Also, hanging mics from balconies or from ropes? Who does this? I have had the pleasure of working with some seriously good engineers (including numerous projects with Bruce Leek) and happen to be one myself and I have never seen this done! Yes, permanently mounted mics for general purpose recording are mounted like this, but the recordings are awful. Mic placement is crucial and if you permanently mount the mics like this, how can you make minute adjustments?
johnthemiracle said:
Huh???
[quote="johnthemiracle]
1. proximity effect? not necessarily that close...but don't forget, some soloists move significantly when playing (half a meter and more from left to right), especially in a concert situation...
2. that's right. i'm not so much worried about sound coloration than about panning the instrument around due to the spaced mics...
[/quote]
1. Yes proximity effect - you will get proximity effect of a classical/acoustic instrument noticable from about 12 feet and closer. The omnis will represent the entire frequency regardless of spacing. To pick up the lowest overtones of the flute, you have to get very close with cardioids. This is not a problem with omnis. And regardless of moving around - that's what omnis are good for! Do you know the concept/definition of an omni microphone.
2. You aren't worried about coloration? Of a classical acoustical instrument? You have displayed by this one sentence that you should not be working with classical musicians. Please for everyone's sake, I hope you were kidding. Panning is easy and you can play with infinite combinations of placement after the sound is recorded. Coloration can and will ruin a flute recording!
johnthemiracle said:
that's the reason why you'll have most phase issues with ab, it's built on that...
No, no, no! That's why A-B is so good for phasing. Perhaps a course in orchestral mic'ing is in order!
[quote="johnthemiracle"
i agree that xy is probably the most phase friendly setup. the stereo width however is not as impressive as with ab. ms should have absolutely no phase issues with a soloist placed directly in front of the m mic...btw. i've heard good ms recordings even with different mics...[/quote]
I will agree with most everything you said here, there are valid points. However, it is physically impossible to not have phase issues when you introduce a second mic into a setup. For that matter it is physically impossible to not have phase issues with a single mic set-up. That is, of course, unless you are performing a venue with absolutely no reflective surfaces. Hmmm... a recording in outer space...
johnthemiracle said:
yes...they also often use a decca tree to avoid the hole caused by widely spaced ab's...after all that's how they came up with that idea...
WHAT??? None of these recording studios ever uses a Decca Tree! The Decca Tree was not invented to subvert the issues with A-B, it is simply a modified A-B, one used to give greater depth to recordings. I only know of a handful of studios that use Decca Tree anymore for recording orchestras. It doesn't pick up natural reverb and therefore must be processed. Though it works acceptably well in movie scoring studios for that reason!
johnthemiracle said:
this is a myth. ortf has been found by mathematic calculation. it just so happens that the 17 cm are close to the width of our heads...and the angle has absolutely nothing to do with our ears but with the recording angle you are trying to achieve....
john...if you read the journals made during the discovery of ORTF, you will discover that measurements of the human head were an integral part of the creation of ORTF. And the 110 degrees is the best angle to recreate the positioning of the outer lobes of the ear. While it may not have been the only factor involved, it certainly was a factor.
johnthemiracle said:
omnis in an ortf setup are not a really good idea since you get super small ab...i tried that once by accident, it didn't sound right...very poor spatial resolution...
I agree with you, I was simply making a factual statement. However, I would encourage you to adjust your distance to the orchestra. omnis spaced at 17cm and angled at 110 degrees should give more than adequate spatial resolution as long as the distance to the orchestra is great enough. Agreed though, it is not optimum.
johnthemiracle said:
when i think about it, i like your idea of using ab for a soloist. you won't get a hole too easily because the soloist is actually in the middle. and you'll capture the full room sound. i just don't see why you couldn't achieve that with ortf in a more mono compatible way...
Mono compatible...why? If, in this particular recording you want a mono flute, mic with just one good omni. If you want stereo, record in a good stereo pattern. Mono compatability has a great advantage for an entire recording of a rock/pop/jazz group, but is nowadays useless when recording a single instrument that will be panned to a stereo field within a recording.
I don't want to enter flame territory here, so I will respect any last post you wish to retort with, but will not respond. If you would like to take this offline, I would enjoy further discussing this with you and perhaps even share some demos of good A-B micing. My e-mail is
jeremy@sssweb.net.
J...
