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Q. I have a Philips 437 turntable with a Stanton 681EEE cartridge that is rated for a minimum tracking force of about 14 to 1 gram. Unfortunately, I didn't know when I installed it that I should be compensating for the brush weight of 1 gram. Thus the effective tracking force was only about 1/4 gram, and I played my records several times under these conditions. In addition, I had the antiskating set so that it was off by a full gram. How does the mistracking affect a record's sound? Is it really worth buying brand-new records if my cartridge was mistracking? -Pat Nilson, Philadelphia, Pa. A. There evidently are two points of concern here: what reproduction sounds like if settings are too low, and what the effects on the record, and therefore on future playings, may be. Distortion rises rapidly as tracking force is decreased below an acceptable minimum, which will vary, with a given pickup, from arm to arm and from record to record. (The setting of the antiskating is a less important contributing factor.) In most setups you should hear nothing amiss if you're a little below the manufacturer's minimum recommendation. As you continue to decrease vertical tracking force, the peaks will distort, and at progressively lower recorded levels. The effect is quite obvious; if you don't hear it, the tracking presumably is okay. Since the audible distortion comes from loss of stylus/groove contact, leaving the stylus tip free to bang around in the groove much like a skidding car careening down an icy highway, it does imply groove damage. If you hear it, stop playing the record and find out what's wrong be fore you continue, or you may cause permanent damage. I recently purchased a Sansui G-7500 receiver. It is equipped with a mike mixing control, but the operating instructions give no indication whether or not this feature can be used to mix live material with another source (FM, phono) for recording. Is there a way this can be done? -Tom Grimner, Borger, Tex. A. Since your manual doesn't ad dress the recording question, we assume the G-7500, like most receivers with "mike mixing," is designed just for sing-alongs with accompaniment from any source including tape playback. This scheme puts the mixer after the tape connections and thus prevents recording the mix via the normal tape-output jacks. By far, the easiest and most efficient way to mix live and recorded pro grams for taping is via an outboard mixer or through the mike mixer built into some cassette decks. If, however, the receiver is equipped with pre-out/ main-in jacks, you can use them temporarily for your recording by connecting PRE-OUT to the deck's recording input. In order to monitor what you are doing, you will have to turn off your speakers Ito avoid feedback) and listen on head phones. You can connect the deck's out put to the MAIN-IN jacks. With this setup, however, the volume control is ahead of the deck input and now is acting as a master fader in your "mixer." If your deck has an output level control, it can be used to adjust headphone listening levels; if not, the deck's jack. My system consists of a Fisher 450-T receiver, a pair of KLH 5 speakers, a B.I.C. 980 turntable with a Shure M-95ED cartridge, and an Akai GXC-706D cassette deck. When I play a record, I am disturbed by an annoying sibilance in the left channel. It is not severe enough to be heard all the time, at all program levels. I've reversed the speakers, but the sibilance stays in the left channel, and it doesn't appear at all on FM. Am I correct in assuming that the phono preamp is the culprit? If so, is it time to retire my ten-year-old receiver? -Joe Orlando, Bridgewater, N.J. A. Don't be so hasty about putting your receiver out to pasture. Chances are the problem lies in the phono cartridge. First, check to make sure that the pickup is properly aligned and that the antiskating bias is set correctly. If the problem persists, remove the stylus assembly and inspect for signs of a bent stylus shank or, with a magnifier, tip wear. Whether you detect the source of the trouble or not, we'd still suggest you begin replacement plans with the cartridge; for one thing, it's the least expensive element in the system. Did I just lay out 180,000 yen for a metal-ready deck for nothing? According to Robert Angus in "My Own Christmas Shopping List" ["The Autophile," November 1979], it appears that one can record metal tape on a nonmetal machine and get good results. He states: "No matter that their car stereo units don't have sendust heads and metal playback equalization-or, for that matter, that their home decks don't, either. I'm going to suggest that they record [ with metal tape] on their existing equipment, then play the tapes back in the car...." Could my older deck have recorded on metal tape and realized all the advantages of the pure metal formulation? Or is Mr. Angus confused? William R. Haag, Nagata, Japan. A, You seem to overlook the fact that Mr. Angus was addressing himself to the subject of car stereo. The under-biasing that metal tape experiences in a nonmetal deck will introduce some peakiness into the high end-a zing that some people find appropriate for the acoustics of an automobile. Also, the metal tape will allow somewhat higher recording levels, helping to over ride both ambient noise and tape hiss for better subjective sound. But we would not suggest such a practice for home listening, where accuracy of re production is the overriding criterion. Why is it that all (yes, all) manufacturers who produce racks and rack-mountable equipment show their products with the tuner mounted above the amplifier? All this does is create heat in the tuner. My Kenwood KT-8300 was suffering from drift problems. After a few round trips to the factory to have it repaired, I was asked how I have my equipment stacked. I said that the tuner was above a Kenwood KT-7300 amp. I was told to move the tuner below the amp and appraise the effect. When I did, the problem vanished. And when I asked why the racks are displayed with the tuner above the amp, I was told that this arrangement simply looks bet ter. How can the advertising people get away with their skullduggery when the men who create the products know better? -Edward T. Dwyer, Manahaw kin, N.J. A. Actually, there's another and much better reason to keep the tuner as high as possible in racks: for easy visibility. Tuning can be very difficult if tuners and receivers are well be low eye level, in our experience. This puts a premium on cool-running amps or those whose heat sinking is carefully devised for the available ventilation in rack mounts. Kenwood's manual, like most (except for some micros, where we have seen stacking priorities spelled out in detail), offers only general notes about the problem, even for rack-mountable models. That is where we would tend to put the blame. Of course, had your manuals contained caveats that you failed to heed, the moral would be obvious. HF (High Fidelity, Apr 1980) Also see: Predictable Crises in Classical Music Recording, by Allan Kozinn Audio Research SP-6 preamplifier
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