Tape recorders are available in a number of different head arrangements and speeds. It is the head arrangement, not the tape that governs the formats of what can be made. These include full and half-track mono, two-track stereo, four-track stereo, and quadraphonic stereo. Early reel to reel were "full track". The magnetic head covered the entire width of the quarter-inch wide tape.
1-7/8 ips is the slowest one, mostly used for speech because of much less quality. 3-3/4 ips very common on most decks for both recording music and other media. 7-1/2 ips is used for home high fidelity recording. Generally speaking the higher recording speed is, better quality. 15 ips is for professional use, master recordings or broadcasting. note: there was small portable recorders with 1-5/16 speed and also studio models with 30 speed made. Proper use of the low noise/high output recording concept. Due to the difference when using low noise or high output tape, these improved tapes (high bias) have a higher saturation point. What is that? It's the level at which distortion begins to occur during recording.
If you record and those VU meters are hitting the middle of the red area and even maybe all the way to the right, it will sound very distorted. But using high output tape instead the recording signal can be raised to a higher level producing a very good improved signal to noise ratio.
Two very important factors comprise high quality tape recording. First a wide frequency range and second a minimum of distorsion and noise. Although the frequency response is actually determined by the tape deck performance, and the quality of the tape being used. Variations of the recording level has a great effect upon the end result.
So even if you are using a high-class reel to reel at 1-7/8 speed when recording music, the quality going to be poor because loss of signal pick up and severe background noise. A common thing when using low noise tape, try to stay as close to the beginning of the red area as possible.
When recording normal conventional tapes, set the REC BIAS switch to Normal.
When recording Low noise/High output, always set the REC/BIAS in high position.
FACTS: Sound recordings are made in a strip on the magnetic surface of the tape.
The magnetic strip is called the "track". The full tape width divided by two is called 2-track recording,and the full width divided into quarters is called 4-track recording. 2-track recording is usually employed at music studios for creating masters. In this case both tracks are recorded at the same time and in the same direction. But you can record one track at the time that will give you MONO recording. With other words when using 2-track system the whole tapewidth is used and the other side (B or side:2) of the tape can't be used.
4-track recording, 2 channel stereo: In this mode two tracks are recorded at the same time on the first pass of the tape #1 and #3. The left and the right reels are then interchanged and track #2 and #4 are recorded (side:2). 4-track recording in stereo is the most common way to record. Pre-recorded tapes are made this way.
A four track stereo model can play back, both 4-track and 2-track tapes. When playing a 2 track stereo tape on a 4 track recorder, track #1 will be completely covered by the head. Track #2 however will be slightly off alignment, but stereo still can be enjoyed by compensating the slight loss with adjusting the balance between L + R channel output. Recording: Next step, the difference between using tape/source. Instant listening, how the final recording going to sound is possible with the TAPE/SOURCE switch.
3 head models: from left is the erasehead, then record head, and finally the playhead. When using the switch on TAPE mode, you will actually hear the final recording done on the tape while listening. Recording on old tapes the signal loss can be slight higher, and this is a very good way to check the recording at the same time recording is done.
If the deck only have 2 heads: Erase and a combined play/record head this option is not possible to do. Erase old recordings from the tape: First locate the section you want to erase, whole tape or just some parts. Press both record mode controls. Set the Line and Mic level controls fully counterclockwise.
Cleaning the heads and travelpath:
This should be done every 8-10 hours depending what tape you are using if they are new or old. The heads should always be cleaned BEFORE doing important recordings. Beware of rubbing alcohol, while it's isopropyl alcohol it also contains water and oil that will leave a film on the heads. Head-cleaner or if you can't find it locally a bottle of Everclear will also work.
Dirty heads will cause a reduction in high frequency response and irregular headwear. Any dirt or oxide build-up on the heads will force the tape away from the gaps that record or when you use playback mode. Dirty tape guides have the same effect. Tape can start dragging and dirt from the guides create wrong position of the tape while going over the heads. This will drastically affect the response. Even so small layer of dirt as one thousandth of an inch will result in degraded performance. All the money you have paid for high performance will be wiped out by a bit of oxide. Tape and tape residue act very much the same as fine sandpaper. The combination will slowly grind down the tape path. If you do not clean off this abrasive material on a regular basis, the wear will be much more rapid and will become irregular. Even wear can be compensated for with electronic adjustments for a while, but uneven wear can produce notches on heads and guides that will make the tape to move around making adjustments impossible. This ragged pathway also chews up the tape, producing more abrasive material which in turns causes more uneven wear. This begins a vicious circle that cannot be stopped once it gets a good start. The only solution to this is to replace the heads and sometimes tapeguides as well. Being conscientious about cleaning the travelpath on regular basis will more then double the life of the heads and travelpath. In extreme cases the deck will not record at all. So get a bottle of head-cleaner and some Q-tips.
Use a cotton swab dipped in headcleaner fluid, rub the entire area of the head surface.
Repeat the process on each head until all tape oxide and dirt are removed. Use a clean cottonswab to dry all the heads off afterwards. Clean all the metalguides where the tape passes, such as capstan shaft, tape guides, tape lifters and tensionrollers. Tensionrollers can be hard to clean in the grooves. I usually wipe them down first with headcleaner fluid, and carfully take a toothpick cleaning the inner-grooves that's hard too reach. Second important thing: Don't use headcleaner or alcohol on the rubber pinch-roller. It will destroy the pinch-roller.
In studios the demagnetizer is a important tool that are used every time before a master recording is done. During long periods of use, the heads will become slightly magnetized. A little stray of magnetism can become quite a big problem in tape recording. It only takes a small amount 2 gauss to cause trouble on the record head. A little more like 7 gauss will start erase high frequency signals on previously recorded tapes. You can see that it's worth taking the trouble to demagnetize regurarly. As a result, the high frequency will decrease, noise will develop, or in extreme cases the high regions will drop out or introduce noise ratio. So how often should it be done ? Personally I do this every 20-30 hours of use, not exactly sure what the right time period is. Many people suggest every time a recording is made, or every 50 hours of use.
You can destroy the heads if doing this wrong. First turn the deck off. If you try with the unit on, the current pulses produced by the demagnetizer will look like audio signals to the head. These pulses are around 10.000 gauss, and will seriously damage the electronics and/or meters. Be sure that the demagnetizer has either a plastic cover or plastic tape covering the tip. Make sure that no metal ever touches the heads as it will create scars and some cases destroy them. Be sure to concentrate while you are doing this. If it's turn on and off by accident when close to the head you can put a permanent magnetic charge on them that no amount of demagnetizing will remove. You will have to replace the heads instead. Make sure you are awake and alert for this job. Also clean the heads first before demagnetizing. Attach the the plastic protection on the pole tips of the demagnetizer. Plug the demagnetizer in to the AC outlet. Have all your tapes at least 5-6 feet away (2 meters) when demagnetizing to prevent the magnetic field from erasing them. Depress the button and slowly bring the tip close to the head, move it up and down 4-5 times. Slowly draw it away from the head at least 5-6 feet away from the deck, and release the button. The same procedure is done on each head, and tape guide posts.
The life span of the heads is highly dependent of design of your model and brand. Some models like early Sony's had softer material.
But also combined with pressure pads and no replacement of pads and lack of cleaning many of following models of Sony have severe head wear: TC- 230, 250, 255, 350, 355 and 630.
Example of pressure pad set-up on a Sony TC-910. On the other hand a deck without pressure pads 3000-4000 hours of use is excepted. I don't say every model with pressure pads installed have worn out heads. It depends how many hours of use the deck had in the past and regular maintenance with cleaning was done or not.
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