5121cdd@houxm.UUCP (C.DORY) (03/29/84)
Some interest was expressed to me in exactly what sort of tricks recording engineers play. I will try to explain a few to give an idea on just how "unpure" the recordings we hold near and dear to our hearts really are. One good example in documented in a well-respected book written by John Eargle. In his book, Mr. Eargle explains how there is a high-frequency roll-off due to air absorption. This phenomenon exists and is humidity dependent (the lower the humidity, the less absorption -- this is correct even though it is contrary first thought). Anyway, Mr. Eargle proceeds to explain that do to the air absorption of high frequencies, a 10 to 12 dB rise around 10K Hz. was required when recording organs to compensate for the distance from the pipes to the mikes!! I recorded Anthony Newman in the Cathedral of the Sacred Heart last week. This organ is very large (140 ranks in nine divisions) and so is the Cathedral (reverb time of 4 seconds). I was one hundred feet from some of the pipes. I guarantee you that if I had boosted the high end on the recording, my client's ears would have bled when Anthony Newman kicked in the trompettes (very brash wooden pipes -- lots of overtones). Other "solutions" to the air absorption "problem" is to use mikes that have a rising high-end -- Telarc goes this route. The omnidirectional Schoeps that Jack Renner uses have a 5 dB peak around 10K Hz. Yet another method is multimiking (sacrilege). Something strikes me funny in that all these "tried and true" methods attack a problem that should not be solved. When a symphony plays a concert, the best seat is in the middle of the orchestra section not on top of the musicians. The only seats in a cathedral are the pews -- the organs are designed to play for that audience. One can easily see, then, why many of the CDs sound "awful". A great majority of the masters made today are recorded by "engineers" that use too many of the wrong kind of mikes and then equalize the whole thing right before running it through a limiter (or is it peak limit before running through an equalizer). In any event the CD, in theory, does not suffer from some of the losses that LP does and these sins become more prevalent on the CD. This brings us down to money. The record companies that have the capital to make CDs use the wrong engineers (with exception to Telarc -- Jack Renner is very good even though he uses too many mikes). I was overjoyed in seeing only twelve(!?) mikes on the New York Phil at a recent performance being recorded for PBS. Craig Dory AT&T Bell Laboratories Holmdel, NJ