DENON DH-630S
¥ 295,000 (around 1976)
Commentary
This is a four track tape deck of the two track DH-610S, which is highly evaluated as a professional equipment for broadcasting stations and studios.
A direct drive capstan system is adopted for the mechanism.
The DENON proprietary magnetic recording and playback method is used to detect the rotational speed of capstan motors for direct drives. This method reduces wow flutter and achieves extremely fast tape start-up characteristics. This method controls the rotational speed of the capstan motor by detecting pulses accurately recorded magnetically on the outer circumference of the wheel attached to the shaft of the capstan motor. The capstan motor used in the DH-630S has a smooth outer rotor shape and uses a magnetic material specifically developed to minimize vibration.
The use of a tension servo, which is especially effective for uneven tension in the ultra-low frequency range, eliminates the need for a heavy flywheel. This reduces the moment of inertia of the tape travel system and, combined with the excellent direct-drive capstan system, provides extremely fast start-up characteristics.
Uses the same electronic tension servo as DH-710F.
This method detects the tension of the tape during travel and controls the AC voltage applied to the reel motor. The tape tension (back tension) between the supply reel and the capstan during recording and playback, and the tension of the tape wound around the reel during fast-forwarding and rewinding are kept constant and optimum regardless of the reel size or tape winding diameter.
This reduces the wow in the ultra-low range caused by eccentricity of the reel and uneven winding of the tape. In addition, since excessive tension is not required, wear of the head and tape is small. Since the tape tension near the head is constant regardless of the tape winding diameter of the supply reel, head touch is always stable. In addition, since the tape runs stably and there is no meandering phenomenon, phase fluctuation between stereo channels is small, and excellent orientation and reality can be obtained.
The DH-630S uses a scrape filter roller to reduce the distance to the capstan as much as possible. In addition to reducing the longitudinal vibration of the tape on the head surface, we are also seeking optimum conditions for the angle of the tape in contact with the head and the shape of the head. We also aim to reduce FM modulation noise by minimizing flutter (especially at 100 Hz or higher) generated by the capstan drive system.
A newly designed special guide roller is used for the part where the tape touches other than the head and the tape shifter. It achieves both stable running and magnetic surface protection regardless of the type of tape used, from standard thickness tapes to 200% tapes (total thickness 25 microns).
The hard permalloy head for broadcasting stations with a wide track width is used for the head, and excellent recording and reproduction characteristics with less noise and less distortion are obtained. In addition, the large size of the reproducing head suppresses the expansion of the frequency characteristics (shape effect) in the low frequency range.
Cue / pause lever is used.
This lever operates in pause mode during recording and playback, and in cue mode in conjunction with the muting switch during fast-forward, rewind and stop.
The bias amount and recording EQ characteristics are continuously adjustable so that they can be adjusted according to the tape.
The recording and playback amplifier uses a high bias frequency of 180 kHz to prevent beat interference when recording FM broadcasts.
In the recording amplifier section, the last stage of the amplifier connected to the recording head is a push-pull circuit. The maximum allowable output level of the recording amplifier is 30 dB or higher compared to the standard level, which is the same as that of professional units.
It is equipped with a meter with a changeover switch for peak level indication and VU indication.
Equipped with a microphone attenuator, 12 dB attenuation can be achieved with one touch operation.
When used according to the sensitivity and operating conditions of the microphone, the SN ratio is good and microphone recording with a wide dynamic range is possible.
Equipped with a playback volume with Klix/Klukš top.
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Model Rating
| Type | Tape deck | ||
| Motor used | For Capstan : 6 Pole Outer Rotor Type AC Servo Motor For Reel : 2 x 6-pole AC servo motors |
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| Drive system | Capstan part : direct drive by AC servo motor Reel Unit : Back Tension Servo by AC Servo Motor |
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| Track format | Two track, two channel stereo system | ||
| Heads | Recording and Reproducing Heads : Hard Permalloy Heads Erasing head : ferrite head |
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| Tape Speed | 9.5cm/s, 19cm/s | ||
| Speed deviation | Within ± 0.5% | ||
| Quick winding time | Approximately 2 minutes and 30 seconds (No. 10 reel, 740m tape) | ||
| Reel Diameter Used | Maximum No. 10 (Type 26) | ||
| Recording bias | Approx. 180 kHz (Bias amount can be adjusted by ± 40%) | ||
| Recording and playback compensation characteristic | NAB standard (recording compensation can be adjusted depending on the tape used) | ||
| Overall signal-to-noise ratio | 63 dB or more for a maximum recording level of 514pwb/mm 55 dB or more (compared to the reference recording level of 200pwb/mm) |
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| Total third harmonic distortion factor | 0.1% or Less (1 kHz Reference Level, When Using 3M #250) | ||
| Overall frequency characteristic | 19cm/s : 20 Hz to 20 kHz ± 2 dB or less 9.5cm/s : 20 Hz to 18 kHz ± 2 dB or less |
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| Channel separation | 45 dB or More (1 kHz) | ||
| Crosstalk | 60 dB or More (1 kHz) | ||
| Wow and flutter | 19cm/s : 0.03% wrms or less 9.5cm/s : 0.04% wrms or less |
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| Input | Mic : 50k Ω unbalanced, -72dB (ATT. off) -60dB(ATT.on) Line : 100k Ω unbalanced, -22dB at VR max * However, 0 dB : 0.775 Vrms |
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| Output | Line : Output impedance unbalance : 100 Ω or less Applicable load impedance : 600 Ω or more Nominal output level : 0 dBm (0 VU) Headset : Applicable load impedance : 8 Ω |
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| Accessory function | Equipped with remote control terminal | ||
| Semiconductor used |
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| Pwer | 100 VAC, 50Hz/60Hz | ||
| Power consumption | 120W | ||
| External dimensions | Mechanism Part : Width 470x Height 385x Depth 270 mm Amplifier Part : Width 460x Height 180x Depth 235 mm |
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| Weight | Mechanism Part : 20 kg Amplifier : 6.5 kg |
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| Attachment | Reel 10 x1 2 x 10 Reel Clamper 2 x 7 Reel Clamper Reel Height Adjustment Sheet x2 One Head Cleaning Pen 2 Pin Cords Socket Wrench x1 Dust Cover x1 |
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