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Readers who sent letters to Herman Burstein between the third week in July and the middle of September and haven't received a reply at the present time ... should please write again. The U.S. Postal Service lost quite a few of these letters for Mr. Burstein and we don't, of course, know whose letters they were. Deck Decision Q. I'm basically interested in a tape deck that is ruggedly constructed, has superior frequency response, low noise, low wow-and-flutter, convenient features, and long playing time. I am now trying to decide between a deck which takes 10 1/2-in. reels and one which takes 7-in. reels but has automatic reversing. -Nicholas Jones, Charleston, S.C. A. If your aim is to have extended recordings with a minimum interruption for changing or turning over reels, your best bet is probably a deck that accommodates 10 1/2-in. reels. Also a machine designed to operate in one direction has a somewhat better chance of giving top performance than one designed to operate in both directions. Taping Trauma Q. Using two microphones about 15 feet apart feeding into the low impedance inputs of my open-reel deck, I recorded a church choir with pleasant results except for some excessive tape hiss. In order to get adequate volume from the soloists I had to turn up the recording gain control about two-thirds of the way. At this point the noise level gets too audible on the quiet parts of the recording. I suspect that if I could amplify my signal a little before it gets to the recorder, I could improve my signal-to-noise ratio. If my theory is correct, I could obtain better final results by using a mixer; is this correct? -Leonard Blanchard, Clayton, N.Y. A. Whether a mixer will improve the signal-to-noise ratio depends upon how quiet its electronics are. If they are quieter than those of your recording amplifier you may be able to audibly improve the signal-to-noise ratio of your recordings. Another possible answer would be to use microphone step-up transformers (mounted at the tape deck end of the microphone cable) and feed these into the high-level inputs of your tape deck. Still another suggestion is to add a noise reduction unit. You should keep in mind that when recording live material with a full dynamic range, tape system noise during the quiet passages is apt to be more evident than when recording compressed material, as from a record or FM station. Signal Loss Q. My problem is a gradual loss of signal level on my tapes. The signal level drops off a bit, then seems to stabilize at this lower level. Sometimes, though, the signal level is further down in some spots than in others, giving an up-and-down effect in playback. This problem occurs more in some tapes than others. -Terrell Cook, Spartanburg, S.C. A. Magnetized heads and dirty heads, particularly the latter, can account for your problem. Dirt causes separation between the tape and the head resulting in reduced response, especially at high frequencies. Thus, to an extent, varying volume might correspond to varying frequency content of the recorded material. Magnetized heads or other magnetized parts of the tape deck contacted by the tape can cause signal loss. Therefore periodic cleaning and demagnetization are required, usually after about eight hours of use. Some tapes shed less oxide than others so they present less of a problem in the tape-to-head contact. It is possible that the tapes which give you trouble have come from an imperfect batch, so that non-uniform oxide coating is causing your volume variations. (Source: Audio magazine, Dec. 1978; by Herman Burstein) = = = = |
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