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TDK DA-RXG Digital Audio Tape
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TDK DA-RXG Tapes - Prices ex VAT
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1+
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5+
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10+
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20+
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| DA-RXG 180 min |
5.82
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5.74
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5.65
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5.56
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| DA-RXG 120 min |
4.65
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4.58
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4.51
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4.44
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| DA-RXG 90 min |
4.09
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4.03
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3.97
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3.90
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| DA-RXG 60 min |
3.49
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3.44
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3.39
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3.33
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| DA-RXG 46 min |
3.20
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3.15
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3.10
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3.05
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| DA-RXG 30 min |
2.91
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2.87
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2.83
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2.78
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| DA-RXG 16 min |
2.62
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2.58
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2.54
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2.50
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TDK DA-RXG Tapes
With its DA-RXG, TDK have come up with a tape that achieves an extremely low and stable block error rate, uncompromising reliability and a long lifetime, such that it will satisfy even the most demanding high-end audiophiles.
The DA- RXG is designed and produced according to the principle that error prevention is better than error correction, and will fully unfold the potential of the DAT format.
The following will give an overview of the technologies that have gone into TDK's DA-RXG. First though, some calculating may help to understand, why DAT puts tape technology to the limits.
Why DAT is so demanding
With a maximum sampling frequency of 48kHz and 16 bit quantization, a mere second of monaural music is represented by 768,000 bits of data. Converted to stereo, this figure swells to approx. 1.5 million. Add to that error correction, tracking data and a host of control signals, the DAT tape ends up handling nearly 3 million bits of data per second, or, for a two-hour recording approximately 20 billion bits, every one of which has to be correctly recorded and played back.
DAT's absolute tape speed is a mere 8.15mm/sec. In order to record and retrieve the enormous amount of data, however, the rotating record/playback heads travel at a speed of 3.1m/sec relative to the tape, tracing an extremely narrow track only 13.6µm wide. If we multiply the tape width, 3.81mm, times the distance the tape moves in one second, namely 8.15mm, we get 31sq.mms or the area covered by the head in one second. Hence, the DAT tape has to somehow store 3 million bits of information in the space of 31sq.mms and then find them all again in the right order every time the tape is played back.
Understandably, a tape that could cope with this load of information has to be capable of an extremely high number of flux transitions per inch, or ftpi for short, as any flux transition (a change of the magnetic polarisation of the magnetic layer) represents one bit of the digital signal.
While a DAT recorder possesses a powerful electronic system for error correction to handle minor dropouts or other data errors, when whole strings of data are corrupted - so-called burst errors - even the best electronic countermeasures won't be able to patch up the signal, and sound quality will be seriously degraded by clicks and pops. That's why every effort has to be made to get the error rate on the tape side as low as possible. In addition, the rapidly rotating heads and the DAT search function at a speed 200 times higher than normal running speed impose very high durability requirements on both tape surface and overall tape strength.
Features of the TDK DA-RXG DAT tape
Newly developed ultrafine high-performance metal particle coating for high-output characteristics With a shortest recording wavelength of 0.67µm, the DAT system requires a tape with pronounced high density recording capabilities. At the same time, output characteristics with a sufficient safety margin are necessary to faithfully deliver the digital signal.
Translated into recording media technology, these features call for a high-density coating of ultrafine high-output metal particles with even distribution in the magnetic layer. With its newly developed high-power metal particle formulation and its new high-dispersion binder system, TDK's DA-RXG realises a magnetic layer of amazing characteristics. Hardening of the binder is done within seconds rather than by being subjected to heat for several hours. Thermal stresses that could cause basefilm deformation are thereby avoided. In addition, the binder's excellent dispersion characteristics provide for superior uniformity and density of the magnetic coating.
TDK's DA-RXG is impervious to magnetic losses caused by frictional heat and pressure from the fast moving heads. There is no problem with self-erasure at short wavelength, either. The tape delivers high output across the full frequency band with more than sufficient headroom. Its extremely low error rate puts the TDK DA-RXG in the vanguard of the emerging family of digital recording media.
Mirror-smooth surface finish eliminating spacing losses
Since DAT recording makes use of extremely short wavelengths, a mirror-like smoothness of the tape surface is every bit as important as the magnetic layer itself. Even the most minute surface unevenness may interrupt head-to-tape contact and cause dropout errors commonly referred to as lift-off or spacing losses. Hence, special attention has to be paid to the basefilm, as, owing to the exceedingly thin magnetic layer, any irregularities would be immediately transferred to the tape surface.
In the DA-RXG tape, TDK uses a super-smooth basefilm which, despite its thinness, features high tensile strength and superior flatness. After the magnetic layer is coated onto the basefilm, the tape undergoes a calendering process that smooths out any surface unevenness to within 0.02µm. The resulting super smooth finish allows for an unprecedented C/N ratio, for spacing losses reduced to an absolute minimum and, hence, for a precise transfer of the digital data. What's more, due to the mirror-smooth surface finish headwear is extremely low, translating into a longer headdrum service life.
Tough 5-layer tape construction to withstand high-speed search and years of hard use Rotating magnetic heads are especially prone to head soiling and, finally, clogging. Once the head gap is clogged, recording and playback of the digital signal will be impossible. The binder has therefore been customised to provide for optimal bonding of the metal particle formulation specifically developed and applied for TDK's DA-RXG. Particle shedding is efficiently prevented and the magnetic layer is rendered considerably tougher and more abrasion resistant than with conventional binders. Moreover, both sides of the basefilm feature a high-adhesion treatment resulting in a structural integrity of magnetic layer, basefilm and backcoat, that cannot be undermined neither by the rigors of 200 times normal speed search nor longtime use or storage.
Tailor-made backcoating for superior tape runnability
A dilemma in the design of magnetic tape is reconciling the need for extreme surface smoothness (to insure intimate tape-to-head contact) with the problems that arise when runnability is hampered by the tape clinging to mechanical parts. TDK´s DA-RXG tape overcomes this problem, first, by imparting a lubricating effect to the magnetic layer surface and second, by applying a tailor-made backcoating that reduces frictional drag to the level of optimal tape runnability. Furthermore, the backcoat features antistatic properties, thus avoiding the attraction of dust or any foreign matter that could cause dropouts.
TDK's DA-RXG tape is available with playing lengths of 16, 30, 46, 60, 90, 120 and 180 minutes. It comes in a soft plastic case ensuring dust-free archiving.
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| SPECIFICATIONS |
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Item |
DA-RXG 124 |
| Physical properties |
Tape width |
3.81 mm |
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Tape width fluctuation |
0.003 mm |
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Tape total thickness |
13 µm |
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Magnetic coating thickness |
3 µm |
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Base film thickness |
9.5 µm |
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Back coating thickness |
0.5 µm |
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Tape length |
60 m |
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Yield strength |
7.5 N |
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Breaking strength |
12 N |
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Electrical resistance of magnetic coating |
1 G¸/sq |
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Electrical resistance of back coating |
1 M¸/sq |
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Light transmittance |
0.02% |
| Magnetic properties |
Magnetic material |
Super Finavinx (metal) |
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Coercivity |
120 KA/M (1500 Oe) |
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Remanence |
230 mT (2300 gauss) |
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Squareness ratio |
0.80 |
| Recording characteristics |
Optimum recording current |
0 dB |
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RF output level (4.7 MHz) |
0 dB |
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RF output level (130 kHz) |
0 dB |
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RF frequency response (4.7 MHz/l.2 MHz) |
0 dB |
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RF frequency response (1.5 MHz/l30 kHz) |
0 dB |
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C/N (4.7 MHz/3.7 MHz) |
0 dB |
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Overwrite characteristics (1.2 MHz - 4.7 MHz) |
0 dB |
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Overwrite characteristics (130 kHz - 1.5 MHz) |
0 dB |
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all information courtesy of TDK (UK) Limited
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