SONY TC-7650
¥ 125,000 (released in 1973)
Commentary
This 3-head deck is the culmination of Sony Deck technology and was developed using Sony's technology.
This is the first tape drive system in its class to use the closed-loop dual capstan system.
By placing the head part in the center of a pair of capstan and pinch roller, not only constant head touch can be obtained, but also tape vibration and uneven tension caused by tape running can be suppressed.
The capstan drive motor employs an ultra-low vibration eddy current type motor and an AC servo motor with a frequency generator (FG) attached to its shaft.
It is controlled by a servo amplifier to maintain a constant rotational speed, enabling stable rotation with less vibration.
The head uses an F & F head (ferrite & ferrite) that boasts about 200 times more wear resistance than conventional laminated heads.
It has an all-ferrite structure in which both the core part and the guard part are hardened with ferrite. Furthermore, it is fused and welded with unstrained glass of the same hardness. There is no disturbance of the gap edge, and the narrow gap is maintained semi-permanently.
In addition, since the front surface of the head is finished with a uniform black mirror (mirror surface), the head touch is good and dust adhesion is also prevented.
It is equipped with an FM recording mechanism and a lock mechanism is added to the recording and playback buttons. If you use a timer that can be set in small increments, you can record repeatedly as many times as you want by turning the power on / off.
The pinch roller is released during the rest period to prevent excessive load on the mechanism.
With the adoption of logical control, the tape can be freely operated from rapid forward / rewind state to direct regenerating condition, and from recording / regenerating condition to direct rapid forward / rewind without damaging the tape.
The rotating state of the reel motor is detected by a frequency generator (FG), and after the tape stops completely, it automatically moves to another operating state.
A FET is used for the first stage of the head amplifier, and a direct coupling system is adopted in which this FET and an F & F (ferrite & ferrite) head are directly connected.
Since there is no element that degrades the sound quality between the head and the first stage FET, the output of the head can be directly transmitted to the amplifier.
In order to maximize the characteristics of all commercially available tapes, the bias and equalizer are independent, and a tape selector is installed to provide the optimum bias and equalizer.
Equipped with a microphone attenuator, if the microphone input level is too high, the microphone input can be attenuated to an optimum level of 15 dB or 30 dB.
Equipped with a tension arm for more stable tape travel.
Since this arm is linked to the electric mechanism, it automatically stops when the tape is finished.
Equipped with a pause mechanism.
In this pose state, only the mechanism is stopped, so if you move the reel with your hand, you can get a detailed cue.
Since the microphone input circuit and line input circuit are independent, mixing is possible.
Equipped with a tape height adjuster, the height of the tape can be adjusted when the tape is moved to the reel surface.
Equipped with a reel size selection switch that can be used with 7 inch and 10 inch reels.
Equipped with line-out volume.
We have eliminated the reel cap and adopted a reel lock that holds the reel easily and securely.
Model Rating
| Type | 4-track luxury 3-motor 3-head deck |
| Tape speed | 19cm/s, 9.5cm/s |
| Recording system | 4-track 2-channel stereo |
| Maximum reel used | No. 10 |
| Head Used | Playhead x1 1 Recording Head Erase Head x1 |
| Motor | Capstan AC servo motor x1 2 reel motors |
| Frequency characteristic | 19cm/s : 20 Hz to 30 kHz 9.5cm/s : 20 Hz to 20 kHz |
| Wow flutter | 19cm/s:0.05%Wrms 9.5cm/s:0.08%Wrms |
| Total S/N | 56dB |
| Overall strain rate | 1.2% |
| Input terminal | My Kujac : -72dB (0.2 mV) Standard jack, low impedance Line : -22dB (60 mv) / 100k Ω or more, pin-jack |
| Output terminal | Line : Specified output 0.775V/10k Ω or more, pin jack Emetic : 8 Ω, binaural jack |
| Semiconductor used | Transistor : 56 pcs FET : 2 IC : 1 Diode : 41 |
| Pwer | 100 VAC, 50Hz/60Hz |
| Power consumption | 80W |
| External dimensions | Width 435x Height 451x Depth 215 mm |
| Weight | 23kg |
| Attachment | Reel R-11Bx1 Head Cleaning Rod x1 Set Connection code RK-74x2 Reel Adapter x1 Set |