Tape Guide (Q and A) (Sept. 1972)

Multiple Recorder Hookup

Q. I am wondering whether connecting up to three tape recorders to the tape output of an amplifier would affect signal strength or quality when all three of these machines are recording? If so, can you suggest any method that would not produce a lower quality recording?

-Robert L. Martindale, Arlington, Va.

A. The manner and extent in which signal quality might be affected depends on the output impedance of your amplifier and the input impedances of your tape recorders. Given a fairly low output impedance and reasonably high input impedances, there is a decent chance you might be able to drive three tape machines at once without appreciable signal deterioration. If there is signal deterioration, you can try isolating the tape machines from each other by placing suitable resistance between each machine's input and the output of the amplifier. You might try resistance values between 100,000 and 500,000 ohms. The higher the value, the more likelihood is there of significant treble loss.

Recording In Church

Q. I am going to make a tape recording of my friend's church wedding. In all of the recordings which I have listened to that were made at church ceremonies, the quality of the recording has been poor. This seems to be due to a `booming" response caused by the long distance between the microphone and the voices being recorded. I cannot move the microphones closer to the parties. Is there some way, given this limitation, in which I can get a more natural response?

-Norman M. Moltar, Jr., Los Angeles, Calif.

A. A highly directional microphone--a supercardioid--may be of help. 'This will concentrate on sound directly from the front and will de-emphasize sounds from the side and rear, thereby helping to reduce echo. You might also use some bass attenuation and/or treble boost.

Low Voltage

Q. I have a Revox 636 tape recorder, which has plagued me for some time. The take-up reel refuses to function during recording and playback, although it functions well during rapid wind I have taken the recorder to a local audio dealer, who adjusted the brakes twice, and have taken it to the Revox Corp. in New York several times. They say that they have tested it there for several days, that they reversed the take-up and rewind motors, and have made a few other changes. Revox claims that it always works well there, but as soon as I bring the recorder home and put on a reel of tape, the take-up motor soon becomes sluggish and then stops. Revox also says that it would not be due to inadequate voltage since other voltages would also be affected. If I turn the takeup reel by hand, the recorder records and reproduces well.

-Joseph S. Ellison, Springfield, Mass.

A. Nothing occurs to me beyond what is already suggested in your letter, namely the possibility of a low voltage condition in your home. Have you checked your line voltage? If low voltage is indeed the cause of your problem, a suitable transformer (one that maintains output at a desired level) can be installed between the house outlet and your tape machine.

Extra Bass During Copying

Q. I own a Roberts 400X tape recorder and a Uher 20 tape recorder. When I use the 400X to copy tapes that already have over-emphasized bass, this machine further emphasizes the bass. This has happened not only when I play the tapes on my Uher, but also with a number of other tape machines used for playback.

I wrote to Rheem Manufacturing about the problem and received an answer which one could interpret as a polite suggestion that I have rocks in my head I am not crazy and I can hear. The problem is a very real one. A trip the 400X took to a local repair shop never solved anything.

-M. Glen Bair, Idaho Falls, Idaho.

A. Perhaps the reason you get bass emphasis is that the 400X supplies a little too much bass-not enough to be noticeable or objectionable when copying a flat tape, but becoming so when copying a tape which itself contains too much bass. I suggest that you employ the tone controls of your audio system, if possible to adjust the bass to your liking.

(Audio magazine, Sept. 1972; Herman Burstein)

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