Critic's Corner

Posted by unclestu52 (D) on June 05, 2007 at 23:46:54

In Reply to: RE: I agree... posted by rick_m on June 05, 2007 at 16:32:53

It is interesting that you two are questioning the microphone techniques. I do believe it further advances an understanding of the issue of polarity.

In the case of many 'pop' recordings, I believe you'll find your first statement to be true. Mikes are set up very close to, and actually within the instrument at times. Mikes are within a drum kit, and are often clipped to the bells of the various instruments, and thus they are often actually employing what you are advocating (in saying that the recording should be 'dry' as possible.

As far as orchestral recordings or large scale ensembles, the distance does become critical. Binaural, or single stereo mikes are very good and avoid most issues. Decca, as you are probably aware of, used a 'tree', a 'T' shaped jig upon which the various mikes were mounted with different patterns depending on what was required. Here, the mikes employed were roughly about 3 to 4 feet apart at the maximum.

TSP (truthseekerprime) is very correct in stating that the distance between the mikes present a potential problem in recreating a phase correct experience. Audio wavelengths can be very long, over 30 feet in length and also very short. Here a cue can be determined by the average distance between a set of human ears: say about 6 inches or so.

However, the situation of recording live is somewhat ameliorated by the triangulation of the placement. In the case of the Decca 'tree' the mikes are placed, say, 40 feet away from the ensemble. While the mikes may be a slight distance apart from each other, they are roughly equidistant from the ensemble itself. The result is manifested in the sound obtained: things are more coherent and more consonant with what you hear in real life. Use of a cardioid pattern will eliminate a certain amount of crosstalk between the mikes, which can help.

In contrast, listen to the Decca recorded Phase Four albums. They are heavily multimiked and the perception is that you are sitting within the orchestra. Many of the classic RCA's have similar sound, though maybe not as apparent. The highly lauded RCA Reiner/Scheherazade (TAS super disc list) falls in that category. I believe only the first three stereo recordings were minimally miked: The Reiner/Zarathustra [LSC 1806], the Fiedler/Gaite Parisienne [LSC 1817]and the Munch/Daphnis and Chloe [LSC 1893]. These are minimally miked recordings and sound very different from other RCA's which typically use 6 to 7 mikes.

In the case of the Scheherazade, the listener can hear anomalies in the three dimensional soundstage presented. The various solo instruments zoom to the foreground and when their solo is over, retreat back into the orchestral mix.

The most interesting microphone technique currently employed is the one designed and utilized by Ray Kimber. His operating principle was to try and recreate the typical loudspeaker set up but to avoid the phase issues by having mikes set up say 10 to 12 feet apart, the typical distances most speakers are placed apart.

It is not an inexpensive set up, but it has fascinating results and is very realistic. The set up is only available at Weber State auditorium, IIRC, but the recordings there are superb, although not all the University's music students may be quite deserving of the quality of the recordings. In addition, Ray employs several other 'tricks' in order to get very realistic recordings. I've seen him advertise the sample discs he has on AA with all proceeds going to the Weber State Music program. If you have not heard his recordings I would highly encourage you to try them. The technique obviously will not be universally adopted, but they remain as a fascinating experiment in the recreation of a live event, and a very realistic one at that.

Stu