Some decks also use the power from one of the motors to load the tape and close the tape door or drawer.Ĭomparing the difference between the sound going into the deck, known as the source, and the sound actually recorded on the tape is not available on double decks. One motor spins each pair of spindles, and one rotates each capstan. Four motors drive most good double decks. That translates to one motor for each tape spindle, and a motor for each of the spinning capstans that drive the tapes past the heads. In an ideal world every moving part operates from its own motor. The least expensive decks squeak by with two motors the most elaborate glide along with six motors. The more motors the merrier when choosing a double deck. Although this will not improve the sound of the original it will minimize copying loss. It`s OK to record onto a higher quality tape. Copying a Type IV metal tape to a budget Type I tape produces disappointing results. Therefore, always choose a tape for the copy that at least matches the quality of the master tape. If the original is recorded at a high level, the copy may overload. Most double decks do not allow you to adjust the recording level of the copy.

Since HX-Pro is not a noise reduction circuit and needs no decoding, it is transparent when copying. This in turn confuses the Dolby circuits when you play back the copy. This is because level variations on the tapes and within the machine changes the Dolby level of the tape. Copying a Dolby tape straight through from one transport to the other, with both of your machine`s Dolby circuits in the off (or ''out'') position results in a lower quality copy.

When copying a tape already encoded with Dolby noise reduction, always decode the tape during playback, by leaving the Dolby circuit turned on and re-encode the tape in Dolby on the recording side. Light passes through the clear leader to a photocell that signals the deck to reverse the tape in one to two seconds without playing the leader tape to the end. The better autoreverse models, often labeled ''quick reverse,'' employ a light beam to trip the reverse. That means you miss several seconds of sound while the clear leader tape plays through and tugs on the hub. The least expensive autoreverse models depend on tape tension to trigger the reverse. The better models feature automatic reverse. The least expensive basic decks require you manually to flip the tapes by hand to copy both sides. The result of high speed dubbing, is that unless you use the best tape on the best decks, the treble sounds dull or muffled. The altered playback level of high speed dubbing also affects how the Dolby noise reduction circuits operate. When playing back the new copy at normal speed, the top frequency response sags to 10,000-12,500 Hz. Doubling the record speed only increases recording frequency response to about 20,000 to 25,000 Hz. Doubling the playback speed doubles the highest frequencies from 15,000 Hz to 30,000 Hz. High-speed dubbing penalizes sound quality. This moves the tape at double speed in both transports, halving the time needed to copy a tape. Nearly all double decks include high-speed copying, or dubbing as they say in the industry.

Dual tapedeck