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Very little appears in Beta literature, advertisements, or support materials about audio quality. This is because in the beginning their monaural recording capability was nothing to brag about. VHS was even worse. About the only place to find their audio performance specifications was in the service manuals like the ones shown above. The best that can be said about Beta's mono reproduction was that it was just adequate. Click on the picture and see what I mean. Shown above is one of the service manuals close up, and you can see from the specifications in the circled area that audio response was not very good. Of course we all know that changed when Betahi-fi stereo came along, but before that both formats, Beta and VHS, sounded pretty dull. Click on the picture again and look closer at the stats. How important is sound quality, and what makes it important? Despite what you may think, humans are limited to a very narrow range when it comes to high and low sounds. Elephants and whales communicate using a much lower frequency (wave vibrations are called Hertz or cycles) that we can't hear, and dogs easily beat us in the higher ranges. So when it comes to sound reproduction, why even reproduce these high or low ranges that we can't actually hear? The argument goes that you can feel the lower range, it adds body to the bottom of a musical passage or sound; and the ultra highs deliver clarity and sparkle, and this adds more punch. But everyone can agree that if the highs and lows fall off inside our audible range (it's normally 20-20,000Hz) audio loses its fidelity and begins to lack definition and body. This happens because some of the audio is missing and this lack of punch is particularly noticeable in the higher range. So let's look at the graphic above and see how the audio playback of monaural Beta, shown on the left, stacks up. Remember now, this is before the introduction of Betahi-fi stereo. In these early Betas, sound was recorded using a stationary audio recording head as the tape passed by it (at a set speed). You can see from the data above the results were pretty unspectacular. As expected, the best audio was produced when the tape was traveling at the fastest speed. The  speed at 4 centimeters per second (1.6 or 1 5/8 inches per second) yields 50-14,000 Hz. of the sound spectrum. That means that anything above 14,000 (14,000-20,000) isn't getting recorded, it will be missing when played back because it is beyond the capability of the recording system. Most of the fidelity you hear comes from these higher ranges. Look how it got even worse when the tape was slowed down to provide for more recording time.  at 2.0 centimeters per second (0.8 or 13/16 ips) losses another 2,000 and  at 1.33 cps (0.5 or 17/32 ips) becomes down right dull after losing another 3,000. No wonder Sony invented Betahi-fi! But now go over to the VHS side of the ledger and things really get depressing. Their fasted speed only goes up to 10,000 Hz. Their best starts out with only 10,000 Hz. at the top. Their slowest speed, called EP or EXP or SLP depending on the manufacturer, your lucky to get any fidelity at all. From this comparison you can see when it came to monaural audio Beta was slightly better overall because of its faster tape speeds. But real sparkling audio would come later when Sony changed the game entirely by putting stereo audio into the video signal. The spinning video heads effectively made the recording tape speed equal to 23 feet per second and this yielded a range that rivaled digital audio (15-50,000 Hz.). That high recording speed almost makes the tape transparent, capable of reproducing everything that the equipment can deliver. One other thing while we're beating up on VHS. I also included here the list comparing the lines of picture resolution for the two formats because that was something else neither format went into much detail about. It was hard to pin down exactly how well each performed; all the figures shown here were taken from a unbiased technical data. That way at least it will be equally accurate or inaccurate depending on their method of testing. One last thing I want to mention before closing. You probably noticed in the above graphic that the lower range of the audio didn't change from speed to speed. This is because the Hertz fluctuation (or cycles per second) for the low range is a relatively long or big wave, and it records easily on the tape. It gets spread out over a larger area when recorded so the slow speed doesn't affect it as much as it does the high Hertz or cycles. They are made by cramming more vibrations into a small space, and that becomes more difficult as the tape area decreases when the tape is slowed down.Note ©Misterßetamax go to homepage |