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![]() Your magazine continues to disregard television. Though high fidelity and TV are branches of the same industry, where is the link between them? And what surprises me most is the lack of public awareness. Even among those who invest heavily in stereo equipment. TV sound appears to be considered adequate. Your magazine should take up this ridiculous anomaly. I'm beginning to think it really is too hot to handle. -Ronald Pataki, Jersey City, N.J. You don't make plain whether you're complaining of TV sound as broadcast or as re produced on typical home receivers. Either way, we agree with all but your statement that we haven't given the problem adequate coverage. TV sound often is execrable, and we've made no bones about it. We have, for example. given particular coverage to various schemes involving stereo sound for video, which-if they had achieved wide acceptance-could have tied the two industries closer together and focused attention on the manifest inadequacies of TV sound. But even when we ran our article (in the August 1974 issue) on recording TV sound--which enumerated the inadequacies in considerable detail-the reader response was largely from specialists of one sort or another. Many of our general-purpose listening/viewing readers may have been awakened to the shortcomings, but if so they didn't choose to let us know about it. So the situation remains: Broadcasters pay little attention to audio quality because the receivers are so bad; receiver manufacturers don't bother because so much that is broadcast is so bad (and a good sound system can show it up even more vividly); viewers, by and large, don't seem to notice. I power a pair of KLH-6 speaker systems with a Sherwood 7300 receiver. The tweeter of each system has on separate occasions burned out under relatively moderate amplification-each time while playing the same piece of music. The speakers were repaired under warranty, but I was under the impression that these speakers, being inefficient, could easily handle all the power my Sherwood could dish out (42 watts continuous per channel). Was I right? -Peter J. Perna, Newark, Del. While what you mean by "moderate amplification" is not clear (the position of your volume control?), amplification is not the issue. Power-in this case power delivered to the tweeter-is. A low-efficiency loudspeaker just makes less sound for the same input power by comparison with an efficient one; it is not necessarily harder to burn out. That your failures are both associated with the same selection suggests that this music has some unusual properties inimical to tweeters, which characteristically will handle far less power than typical woofers. Prudence would suggest that this and similar music be played at lower volume levels in the future-or that the speakers be replaced with ones that can handle more power. When I play back cassettes I have recorded on my Sony TC-177 I often hear peculiarities at the beginning of the tape--a muffling of the sound or a slight fluctuation of the level. I have read that the tape can skew when it starts up and produce effects like this, but they don't seem to occur in the middle of tapes, only at the end. What, if anything, am I doing wrong? -G. F. French, Burlingame, Calif. You may be starting your recordings too close to the splice between the leader and the recording tape. The operators on every cassette assembly line we've seen in operation wear gloves to prevent finger oils from get ting onto the tape's magnetic coating, to minimize the anomalies in response occasioned by the handling necessary in making the splice. But still we find that-even in the best brands and in open-reel tapes as well as cassettes-response tends to fluctuate in the first few inches following the splice. And a drop in sensitivity will, with Dolby processing, produce a muffling in the output. The only cure we know of is to allow a few seconds of "wasted" tape before you begin recording. I have Bose 901 Series II speakers with equalizer. I plan to purchase the Soundcraftsmen preamp 2217 with equalizer. Would the additional equalizer be a waste of money? Should I expect to hear more distortion when using both equalizers at the same time? -Jack Young, Smithtown, N.Y. There is no reason why you should not use a second equalizer with your Bose speakers. The Bose equalizer is designed to correct a frequency-response problem inherent in the drive.. .4. The Soundcraftsmen equalizer is useful for correcting program deficiencies and, to a lesser extent, room acoustics. The only condition we can imagine that would tend to substantially increase the distortion of your system is an attempt to get more bass from the Bose speakers than they now deliver. This should not be done, but correction of bass-shy program material is perfectly acceptable. Do you consider the Marantz 1060 amplifier to be of sufficient quality and to have sufficient power to be used with a pair of AR-2ax speakers? My room is 14 by 12 by 8 feet. Are these speakers suitable for use in a room this size? - Baden Edwards, Tasmania, Australia. The Marantz 1060 is certainly of good enough quality to match a pair of AR-2ax loudspeakers, and the power output (30 watts per channel) is quite adequate. especially in a fairly small room. The usual rule of thumb states that a bookshelf-size acoustic suspension speaker requires an amplifier with 25 watts of output power to drive it. so you have a little bit to spare. The Phase Linear 400 power amp has been criticized on the grounds that it does not have a regulated power supply. However, according to Phase Linear, its power supply can deliver a lot more power on short bursts of out put. I've also heard that with the "perfect" power supply there would be no difference between the continuous power ratings and the dynamic power ratings. Other manufacturers seem to promote the strict regulation of their power supplies as being a virtue of their product. I would appreciate it if you could clarify this matter for me. -Nancy E. Willmott, Detroit, Mich. The transformer and rectifier used in any power supply are imperfect and have losses involved in their operation. The net result is that, as more current is delivered to the load, the supply voltage gets lower. In order to de liver rated output power. the supply must therefore show a reserve of voltage under light load conditions. Assuming that proper margins exist in the amplifier itself, the only effect of this extra voltage is to allow a slightly higher output power for brief transients. Since this is not a problem, it does not make sense to regulate the supply, especially since a regulator would add appreciably to the cost of the product. Why don't the makers of stereo cassette tape recorders put a separate record button on each channel so we can record different material on each of the two tracks? -Stanley B. Gilson Jr., New York, N.Y. The license (from Philips of the Netherlands) under which stereo cassette recorders are built in effect forbids such an arrangement in a machine made for the consumer market. And since channel separation is generally only about 20 dB, even on some fine cassette decks, there would probably be too much crosstalk between the two channels to do you much good anyway. Some while ago I went to an audio dealer to buy a Watts Dust Bug. He replied that he didn't sell the product because it interferes with the proper tracking of the tone arm and increases record wear. Is this true? --Loren Grossman, Toronto, Canada. Your dealer seems to have confused the Dust Bug with a brush device that is mounted on the tone arm (although this too can be made to behave properly). The Dust Bug is mounted independent of and makes no con tact with the tone arm. The only mechanical side effect we have ever observed with a Dust Bug is a slight slowing of the turntable (easily corrected via a variable-speed control) due to increased drag. We know of no reason to suspect increased disc wear. I recently purchased a Wollensak 4765 cassette recorder and was surprised to read in the operating instructions that demagnetization (degaussing) of the tape heads is never required. Will I damage the heads if I attempt to demagnetize? -Fred M. Bindman, Silver Spring, Md. The automatic degaussing feature on your unit will take care of a major source of residual magnetism. However, manual degaussing will not hurt if done carefully and, in fact. may help. ------ (High Fidelity, Mar. 1976) Also see: Too Hot to Handle (Jan. 1977)
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