Q. Some time back I think you ran an article saying that head wear with chromium dioxide cassettes is no worse than it is with ferric cassettes; yet I still hear warnings ( from two dealers, among other people) about not using chromium dioxide if you want maximum head life. Should I be using chromium dioxide, or should I switch to a high-performance ferric brand like TDK SA or Scotch Classic?
- Lloyd M. Davis, Brooklyn, N.Y.
A. The article you presumably are referring to actually said that wear with chromium dioxide is not nearly as horrendous as early re ports had led some recordists to believe.
Chrome is more abrasive than ferric oxide, however, and tests do show that it will wear heads faster. Many home machines have ferrite heads and are used relatively in frequently; in such a situation the transport may give up from sheer old age before the heads wear badly even with chrome tape.
With heavy use and permalloy heads, on the other hand, you should be able to postpone head replacement somewhat by avoiding chrome.
TDK SA is a possible alternative. But, though it is intended for use with the same bias and equalization as chromium dioxide tapes, it is more sensitive than chromium dioxide and ( assuming you use Dolby B noise reduction) would require some readjustment of your recorder for optimum Dolby tracking.
Classic, unlike SA, is a ferrichrome-that is, it has a layer of ferric oxide under a surface layer of chromium dioxide-which obviously determines its wear properties.
Q. For several years I have been using a "One Wipe Dust Cloth" on my records, and it seems to remove dust and fingerprints well, without leaving harmful deposits. Will this hurt the records in any way? Sometimes I use a Watts Preener. How does this compare with other devices of this type? Is it best in using such a device to rotate the record by hand--or should it be rotated on the turntable at 33 1/3 rpm? Lastly, are all brands of poly lined sleeves equally good?
- Mike White, Petaluma, Calif.
A. Without knowing exactly what chemicals are used in these dust cloths, it is impossible to say whether they are safe for records or not. It would seem prudent, therefore, to use only cleaning products that are specifically meant for records-and formulated by reputable manufacturers. The Watts Preener is among the most respected devices of its type. The manual for Watts record-care products gives no instructions as to whether the record is to be turned by hand or power on the turntable, though it may be a little awkward to use with the record placed on some turntables.
Poly-lined sleeves represent a dilemma: To be sure, they keep away dust, but-depending on their own chemistry and that of the record-they can cause plasticizers to migrate in or out of the disc, rendering the vinyl too soft in the one case or too brittle in the other. Where the effect is extreme, therefore, it could contribute to premature record wear.
Q. I came across an Audio-Technica ad, and I would like to know if the claim made about its Shibata-tipped cartridges is justified. Does the Shibata stylus make four times as much contact with the record groove as an elliptical stylus? Does this make record wear one fourth as much?
- Michael Mainiero, Lynnfield, Mass.
A. It is true that the Shibata stylus distributes its contact with the record groove over approximately four times the area that an elliptical stylus does-as does practically any stylus designed for CD-4 use. This means that the pressure exerted on the vinyl surface with a CD-4 pickup is about one- quarter that of a stereo pickup for any given tracking force. This is offset, wholly or in part, by the generally higher tracking forces that such cartridges require. So, though the pressures may be lower with a Shibata, don't expect them-let alone the record wear-to be one fourth as much.
Q. Your review of the Royal Sound Add-N-Stac cassette storage modules [test reports, August 1975] was very enthusiastic. But I use 8-track cartridges. Does the company make 8 track modules, and are they equally good?
- A. Robert Walters, Detroit, Mich.
A. Yes, it does; no, they aren't. We found them an overly snug fit for some cartridges unless we discarded the cardboard covers. The 8 track storage unit therefore encourages discarding the covers, which sometimes have fuller notes than there's room for on the la bels of the cartridges themselves and, in any event, add dust protection when the tapes aren't stowed in the storage module.
Q. Switchcraft's new Model 622P1 de-emphasis compensator for Dolby FM seems to be the same as the one you reviewed [ Model 621P1, test reports, April 1975] except that the new one has added inputs for tape playback, level controls for both sets of inputs, and an input selector switch. And it costs about twice as much [$24.95]. I don't really see the advantage of the tape inputs. My dealer has some information from Switchcraft, but he couldn't figure it out either. How is the 622P1 to be used?
- James B. Martin, New York, N.Y.
A. If your dealer has Switchcraft Bulletin 286, which "explains" the 622P1, we can under stand the confusion. We have entertained a high opinion of Switchcraft in terms of product variety and reliability, but that opinion doesn't always extend to its literature. We must say about Bulletin 286 what we said about the instructions on the earlier unit: Ignore it and, instead, think very carefully about the required signal routings in your system. It appears to us that in most setups the new model will offer little if any practical advantage.
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(High Fidelity, Jan. 1976)
Also see:
Onkyo A-7 Integrated Amp (Equip. Profile, Nov. 1977)
Equipment Reports (Jan 1976)