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Quadraphonic Clique II
In response to the Quadraphonic Clique letter in your "Dear Editor" column of June, 1977, I would like to say that my wife and I are the proud owners of two quadraphonic receivers. We enjoy SQ, QS, and CD-4, in addition to having a very good deck for Q8 four channel tapes.
We hope that quadraphonic will come back strong, and we both know that it has almost unlimited possibilities. Here in the Dallas-Fort Worth metroplex area, there are a large number of quadraphonic owners who despair at the limited number of records and tapes presently available.
-Joe D. Marchand, Arlington, Tex.
Lux Amplifier Addenda
I discovered that I had made an error in the schematic for the Lux power amplifier which I reviewed in the November, 1977, issue of Audio. Here is a partial schematic that shows the two spots where I did not note resistors.
Best of the Worst
How about an article on the 10 worst performers of the year, done by your record reviewers? This would be a worthy addition at the end of each year.
I like your magazine very much even though I don't subscribe to it. The reason I buy your magazine off the newsstand and not by subscription is the fact that we Canadians have the worst mail service in the world. In fact, our postal service is not obligated to deliver the current issue until the next one arrives.
-William Dang Calgary, Alta.
On page 34 of the November Audio, I noticed a letter by Boy Wonder W.J.J. Hoge in which reference is made to an alleged statement by Mrs. Edsel.
Please be informed that Edsel Murphy, his family, and any future issue that may come forth from him, are the exclusive property of db Magazine.
We claim this by right, rather than copyright, since Edsel came to live here 'way back in May of 1968 and ever since has been proving to us just how correct his basic thesis is.
We can only assume that his wife's appearance in Audio is yet one more manifestation of the pervasiveness of his law. In fact, I can only hope that Mrs. Murphy's appearance in your pages means that the Murphy clan has moved to Philadelphia.
Larry Zide, Editor/Publisher db Magazine Plainview, N.Y.
Wide Bandwidth Preamp Corrections
I would like to inform builders of the Wide Bandwidth Preamplifier published last February in Audio of a power supply correction and a modification to the RIAA circuit which I recommend. First, the drawing of the regulated power supply published in the September issue was accidently missing two connection dots. There should have been a dot at the junction of R48, D1, C12, and the base of Q11.
Similarly, a dot should have been at the junction of R49, D2, C14, and the base of Q12. I recommend that a 100 ohm, 1/2 watt resistor be installed in series with the base of both Q11 and Q12. Capacitors C11, C12, C13, and C14 should each have separate ground wires to the power supply main ground point. The inductance of a common ground wire to these four capacitors can cause r.f. feedback, and Q11 and Q12 will become oscillators. Do not use phone jacks for power supply connectors, they will cause Q11 and Q12 to blow when connected or disconnected.
The RIAA circuit can be improved a great deal by increasing C1 to 0.0022 mF and R3 to 82 ohms. C1 should be a physically small capacitor. In case the recommended circuit boards are not used, the leads to C1 and R3 should be as short as possible, and the network formed by these two components should not be routed close to any other components in the circuit. It has been stated erroneously in literature mailed out in circuit board orders that a connection dot is missing in Figure 1 of the February article at the junction of R3 and the emitter of Q1. This should have been at the junction of R3 and the base of Q1.
W. Marshall Leach, Georgia Inst. of Technology Atlanta, Ga. 30332
Classified Ad Note
International Audio Review's citation in your classified ad section of a report in the Boston Audio Society's newsletter, The B.A.S. Speaker, appears without our consent or sanction. IAR's editor and publisher J. Peter Moncrieff advised us of the ad's content after he submitted it to you for publication.
When we registered our strong objection, he apologized and promised to eliminate the reference from future advertisements, but said that it was too late to recall the one already submitted. We want to make it absolutely clear that the opinions we expressed in the cited article are those of the member who authored it, not of the Boston Audio Society. The Boston Audio Society makes no endorsements of any kind. It does not endorse the conclusions of the cited article, and it does not endorse International Audio Review.
Michael D. Riggs, Editor, The B.A.S. Speaker, P.O. Box 7 Boston, Mass. 02215
Editors Note: The display classified ad in question appeared in our November, 1977, issue, and was changed by Moncrieff for December.
Dear Sir: The September issue of Audio featured an article about tape print through. I would like to describe an interesting phenomenon that occurs with records. On many of my discs, I hear a pre-echo which is, to say the least, quite unpleasant. A great deal of my records have this problem, but in most the level is low enough so that it doesn't really become annoying.
This is just one of the many problems that records have. They also have sibilant "S" sounds, background noise, and poor sound quality in general. I used to think that some of these problems were due to my system, but after upgrading it with a more expensive cartridge arid carefully aligning it, the imperfections in my records became more apparent. On the other hand, records on imported labels, especially Deutsche Grammophon and Philips, sounded great, Since American record companies have deemed fit to raise their list prices to the level of imports, they should have a product of at least equal quality. I feel that the record companies should try to improve the sound quality of their records to give some justification for their ever increasing prices.
-Robert Herbin Yonkers, N.Y.
Believing as I do in adages, "Love thy neighbor but don't get caught" and "Do unto others and split," I am compelled to share a unique use of the Lirpa I with you. I stumbled upon this quite by accident. In a recent (Mohammad) Ali fight, I am sure that it was the Inoki fight, because before it I wrote: He float like butterfly, He sting like bee, But the jokyo in Tokyo Is the ripoff to see.
Shortly before the exhibition started, I connected the audio output of the TV set to the input of the Lirpa I. In so doing, the feedback from the Lirpa completely obliterated the TV picture. Then I noted another improvement . . . the intermodulation distortion of the sound became so strong that the sound coming from the TV could not be heard. The hum could not be measured in dBs. But I can tell you it Hertz the ears. Because I have a low threshold of ooms (as in Ram Dass ooms) resistance, I went quickly into a trance-like state of bliss. When I came out of the trance, the fight was over. It was the greatest Ali fight I have ever seen. I have also used this same TV Lirpa hookup during the Mr. Whipple/ Charmin' commercials to great advantage.
-E. Claude Farnsworth, Racine Wis.
Several years ago I decided to take the plunge and make a considerable investment in audio gear. On the whole, I have been quite pleased with my decision. Recently, however, I have become aware of a problem which appears to plague most audio enthusiasts.
After giving me years of trouble free service, my equipment has now started to need repairs (coincidentally, this appeared to occur just at the expiration of my warranty period). This did not cause me any distress . . . after all, nothing is perfect. I assumed that obtaining these repairs would be a minor annoyance. But, not so.
Despite the fact that I live some distance from a major urban area, I am able to obtain repairs for appliances, cars, etc. in the local community. Not so with audio gear. One factory authorized station wouldn't even look at my equipment until it had been in the shop for three weeks and they considered that generous. In and out repair times of six weeks are not unheard of.
In addition, some manufacturers and distributors do not seem to be overly concerned about providing service. One well-known manufacturer limited his communication to me to a toll-free line which told me where I might get service. In another situation, the turntable I am using has had three distributors in as many years, and the current distributor seems to be unconcerned about models he did not originally handle.
Initially I was told that repairs were hard to obtain because the equipment was so complex. I pointed out, however, that one model needed a new pilot light which could easily be replaced, while the other component had a mechanical problem. Besides, I doubt that audio equipment is much more complex than, say, a color TV. I cannot think of any other merchandise that is comparable in price, quality, and prestige which offers such shoddy warranty and repair service.
This simply would not be tolerated in other industries. Since my own work requires dealing with closed-circuit TV equipment, I know from experience that service in this field is both fast and efficient. Either audiophiles are overly meek about this situation, or the industry hasn't caught on to the fact that his kind of disservice either has or will nullify most of the advertising thrown at us.
I feel that the number of repair service facilities and the typical repair time for a hi-fi component should be studied by a publication such as yours.
-Bernard R. Kingsley, Apple Creek, O.
Editor's Note: We currently have in house an article examining the service practices and attitudes about warrantees of various major brand service managers and service facilities. While it appears that most audio buffs experience substantially better service than has Mr. Kingsley, it does appear that there are several steps which can be taken by the consumer which will lead to better and quicker repairs. We anticipate that the article will be published early this year.
(Source: Audio magazine, Jan. 1978)
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