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by William F. Ruck, Jr. How does a Person start making location recordings? THIS SEEMINGLY INNOCUOUS QUESTION has many answers. I am tempted to reply, ''Like one pets a shark: carefully," but this does not help the questioner. Actually, there is no easy answer to this question. Every location recording I have done has been a totally different experience from the last-even ones made in the same location. For me to even pretend there are a few universal truths in this area would be incorrect; on the other hand, I can certainly share the results of many years of making location recordings. In my opinion, the best and easiest technique for making a good location recording of a live performance is to use one of the variations on ''single point'' microphone techniques. This is possible, I should point out, only when no (or very little) sound reinforcement is used. This is the method because it uses only two microphones that can directly feed your tape recorder. You also have only two ''easiest' microphone cords to run and one microphone stand to carry. It is also the '"'best'' from a realistic result standpoint, because all the variations on the ''single point'' technique will provide a realistic stereo image. (For more information, read Charles Repka's article in the November 1978, issue of Audio magazine. AKG also had a good article on M-S Stereo Recording Techniques?, which featured the legendary C-24 microphone and included a lot of the mathematics behind the various patterns.) The method's only major disadvantage (other than not being able to use it well when sound reinforcement is employed) is you cannot correct for any performance problems: the weak soloist during the performance becomes a weak soloist on the recording. HYPERCARDIOIDS & BLUMLEIN Note that Brian Preston uses hyper cardioids, as discussed in his article in Studio Sound and reprinted in TAA?, not the cardioid microphones most of us own. If you are lucky enough to have true hyper-cardioid microphones, the two microphones at 90° will work; but I have found that the French "ORTF'' method of two microphones facing apart at about 110° and spaced about seven inches apart provides a very lifelike stereo image when using the more commonly available cardioid pattern microphones. The ultimate best are two velocity microphones (''figure of eight pattern'') in the Blumlein configuration (90° to each other and as close together as possible). However, the B&O stereo ribbon microphone is hard to find and has a very low output; the few condenser microphones available with this pattern are extremely good and extremely expensive. For this reason I recommend using the ORTF configuration with your cardioids. I mount my microphones on a cut-down Atlas TM-1 microphone bracket. The new mounting holes for the microphones are now spaced about five inches apart. To do this requires a 5/8 x 27 tap, which is rare; the entire job is best done by a machine shop. Radio Shack had available some years ago a dual microphone stand adapter (catalog number 33-331) which has not been in the catalog for a couple of years but still might be in a store that has been in business for several years. Shure makes a Stereo Microphone Adapter A27M that looks strange, but can be made to do about any stereo configuration imagined. AKG, Neumann, and Sennheiser also make various styles of stereo mounting brackets. PLACING MIKES The best location for the microphones is impossible to predict, but it has been my experience that it isn't critical to the inch. Most of the time you can be off many feet and have only a slightly different stereo image. The best place to start from until you get a feel for both the room and your microphones is centered, 10-20 feet behind the conductor and at least 10 feet up with the microphones ''looking down" at the performers. In general, the higher you can get the better off you are. Since most stands do not rise very high, you will either have to build your own or assemble stands from available pieces. I carry two different stands. The first is made up of Atlas CS-1 stands with an AKG KM211/2 boom. This stand all by itself will go up about eight feet, and I have an extension made from a destroyed Atlas BB-1 arm threaded 5/8 x 27 on both ends and coupled with a female 5/8 x 27 coupling. This gives me another 31" but the result is literally a little shaky. However, this combination doesn't get high enough for the really big things, so I have another stand, a folding studio boom, the AKG KM212. I have removed the counterweight and use the boom to go straight up. This gives me a stand that reaches over 15 feet safely and has a stable tripod base, but still folds up and fits in the back of my VW Rabbit (a prime consideration-I don't have a van). Another alternative is Shure's S15 tripod microphone stand, which is basically a modified photographic light stand. If at all possible, try to attend a rehearsal. While the acoustics in most large buildings change dramatically between ''empty'' and ''full,"' the rehearsal gives you an idea of what will be happening; where the orchestra/chorus/soloists will be; where you can set up your equipment; where you can find AC (unless you run totally on batteries); and at least hints on levels and microphone placement. The "fudge factor'' I use in placing microphones is about 25 percent experience, 25 percent instinct, and 50 percent luck; I have no secret formulas. Just remember, the 'echo' will decrease when the building is full and the high frequencies will also decrease at the same time. Both effects are due to the differences between empty seats and people with clothing on. The most dramatic difference will be in churches because you will then change from hard wood/stone/concrete to soft people. WHICH MIKES? What kind of microphones should you use? I do not want to infer that only the following are good microphones; but in general spend as much money as you can. If you can afford them, Schoeps microphones are, in my opinion, the best available today. A pair will cost at least $1,500 (ouch!) depending on what patterns you desire and what accessories you get. Since few of us (including myself) are able to afford microphones of that calibre (I am fortunate to be able to borrow them), a very good reasonably priced microphone is the Sennheiser MKE series. This microphone has omni, cardioid, and ''shotgun'' modules (the latter is not too useful for recording music), and can be purchased for about $400 the pair. Shure's new SM81 is called "The Neumann Killer" by my local professional audio supplier. It is an excellent cardiod microphone and is priced about the same as the Sennheiser MKE series. It will only operate with phantom powering, however; the Sennheiser will work with internal batteries. Both Sony and Radio Shack sell stereo microphones that have basically two cardioid electret elements inside a club-shaped head. These are inexpensive, make respectable recordings, and are the most painless way to begin. Don't neglect dynamic microphones. The better ones are almost as good as condenser microphones don't need power and don't pick up RF. Unless you have professional quality microphones with balanced outputs, you will find yourself hunting mysterious hums and buzzes. Keep your microphone cords as short as possible and experiment with placement if necessary. Actually, even balanced microphone lines (especially "phantom powered condenser'' systems) will pick up noise at times. The worst offender in San Francisco, where I live, is TV RF which sounds like a buzz that changes pitch. Locally we have a very high powered UHF station that gets into everything. Often moving the lines by a foot or so will change the RF pickup so the noise will disappear. GEAR TOTES Unfortunately, most home tape recorders are not packaged for taping on location. The easiest and surest death for a tape deck is to have it fall onto its ''face'' which invariably bends reel spindles and pinch roller mechanisms. If you want to take your reel-to-reel out, be very careful it gets transported on its back with nothing on top of it. If you are thinking of buying a new one, find out if it has a case with covers for the front. Most of the cases aren't excessively ugly and will save you time, money and grief. A cassette deck's front also dislikes being banged. Make sure that while in transit it is packed in a way that the controls (the transport keys) are protected. Check garage sales and flea markets for used typewriter or musical instrument cases. With a little ingenuity with foam, these often make inexpensive cases for your cassette deck. And now some bad news. Due to the way world-wide import tariffs are set up, the main distinction between consumer and professional tape machines is the presence or lack of microphone inputs. Most manufacturers, unfortunately, will tack microphone inputs onto an otherwise good tape deck just to get the consumer classification. While some of the top end machines have microphone preamps that were designed to be used as microphone preamps, you will do better by obtaining or building your own. When you build one, use a good input transformer (best choice is a Jensen JE-115K-E). The Advent MPR-1 microphone preamp is a real bargain. There are better designs, but all for a lot more money. HOW MUCH GEAR? Don't bring everything you own on a field recording: the extra work takes the fun out of making location recordings. I would recommend only: tape recorder; microphones; microphone stand; microphone cables; AC extension cords; masking or duct tape (''gaffer's'' tape is too expensive); recording tape and a couple of empty reels; headphones; a couple of patch cords in case someone wants a copy (courtesy); a flashlight and just enough tools to get by. Until you do it often, make a check list and use it. The most practical transportation device for accessories is a catalog case. These are large rectangular boxes with hard sides that open on the top and will hold a lot of small items; they are also inexpensive. The best monitoring situation is speakers and amplifier in a separate room. If you want to do this, you will have to arrange some form of communication so you can follow the performance. It is a lot of extra work, especially for a one-time recording, so I normally use headphones. While the "'open air'' styles are most comfortable and generally sound better, the ''totally sealed' types are most suitable for location monitoring: you want to hear only what the microphones are doing, not what sound is coming to you at your recording location. Of course, the stereo image is wider with headphones than with speakers, but with a little practice you will be able to ''calibrate' your hearing and make a recording that might sound a little wide on head phones but be perfect on speakers. If you are using a reel-to-reel machine, bring along extra take-up reels. When you need to change reels in the middle of a performance you won't have time to fast-forward or re wind to free up your first take-up reel. Instead, just take both reels off, put them aside, and thread th= next full reel onto a new empty reel. I can change 10%' reels on my Nagra IV-S in less than 10 seconds. Practice at home! TAPE TIP Find out what tape works for your
machine, or have your tape deck calibrated for a given brand/oxide and stick with it. Unless the bias, record level, and equalization are properly set you will be wasting your money and time with other tape types. Read Craig Stark's articles on tape recorder set up , and do it yourself. Don't buy reel-to-reel tape at a hi-fi dealer. For instance, Scotch (3M Co.) has two price structures and the difference is enormous. The typical price for 206 in the fancy box with leader tape (black box with gold letters) is now more than $25, but the "'pro-pak'' package should cost less than $15 (I just bought a case at less than $12 each). Try to buy the tape in case lots as you should get a price break, and the industrial suppliers will be happy to deal with you in that quantity. You may be able to split a 12-reel case with a friend or two. Check with your broadcasting or recording professional friends. They usually know who has the best deal on tape at any given moment in your locale. Once you get a feel for your equipment you should be able to pre-set the recording level and then basically leave it alone. Don't try to ride gain throughout the performance, as you cannot anticipate everything. A short amount of saturated tape is better than drastic and obvious gain changes. Most performances are fairly consistent (after all, you went to a rehearsal) with the exception of female soprano soloists-they somehow can belt out a note 20dB above anything else! PROPERTY POINTS Although I am not a lawyer and this is not legal advice, here is a word or two about the legalities of making a recording. The rights to a performance belong to the performers and nobody else. If they are kind enough to let you record their performance you should reciprocate by not making copies for anybody else without the performers' prior (preferably written) consent. Don't plan on getting rich making recordings. Most of the location recordings I do are for later re-broadcast, and the ''overhead'' comes from other sources. I do charge $15 per hour for 4-track stereo or cassette dubs, but this won't even make the payments on my Nagra IV-S. If you try to make any profit, the performers will simply find somebody else who will be happy to do it for free. (Quality apparently doesn't count if the price is low enough.) You will also find that most performers of any quality are union and generally have restrictions on recording: they expect to be paid extra to be recorded for any purpose. You can then either (1) record it and not tell them-risky at best, (2) pay the price if you have the money, (3) try to talk them out of it, or (4) record something else. Which runs into another problem: musical quality. Most non-professional (and non-union) groups that welcome someone taking the time to record them are inconsistent at best. You may end up with a technically perfect but musically flawed recording. Don't give up for two big reasons: (1) no matter how bad they were, you probably learned something you can use next time about the room or your equipment or the instrumental group, and (2) maybe next time they will be a lot better and will let you record them again if you were nice to them before. It doesn't pay to make enemies. I didn't mean this essay to be a comprehensive guide to 'how to make a location recording.'' To cover this subject in complete detail would take many volumes. However, I wanted to provide some advice from my experience and, I hope, motivate you to get out and make some recordings. It's a lot of fun, and your recordings always sound better! ------- About the author: Bill Ruck is a native San Franciscan, currently engineering manager for KFOG (FM) and Chief Engineer for KUSF (FM), both in San Francisco. At KUSF he built the entire station from "microphone input to antenna,'' including consoles and 3.5kW FM transmitter. He's been interested in sound and audio for about 15 years, starting on location recordings with Ampex PR-10's and slowly graduating to other equipment; currently a Nagra IV-S with QGB 10.5" adaptors. He produces programming for KUSF and provides technical support for live recorded concerts for KQED-FM in San Francisco. He also worked with location sound reinforcement in the late 60's and early 70's in San Francisco. He previously taught ''Radio- Television Broad cast Engineering'' in San Francisco and holds a teaching credential for that subject issued by the State of California, but is now a victim of Proposition 13! His other interests include photography and computers/data communications (not microprocessor based, but full scale systems). ----------------- REFERENCES 1. A Guide to Coincident Mikes, by Charles P. Repka, Audio, November 1978; pp. 40-50 2. M-S Stereo Recording Techniques, AKG Acoustics, 91 McKee Drive; Mawhaw, New Jersey 07430. 3. A Coincident Microphone, Brian Preston. Studio Sound, November 1977; pp. 34-36 and also reprinted in TAA 4/78; pp. 26-2 4. A Tall, Portable Microphone Stand, by Alan S ot Douglas. TAA 4/76; pp. 26-2 5. The Advent MPR-1 Microphone Preamp, by Frederick M. Gloeckler, Jr. TAA 2/1979, pp. 5-10 6. A to Z Tape Recorder Set-Up, by Craig Stark. Part 1, TAA 3/76 pp. 6-9. Part 11 TAA 4/76 pp. 16-25, 27 ---- Also see: Audio Aids---On Heils, ladders, head leveling and Zeners. The Williamson 40/40, Power Amplifier--Return of an improved favorite after a decade
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