Pioneer XL-1550
¥ 59,800 (around 1976)
Commentary
A record player with a quartz PLL.
Quartz PLL system is adopted for servo circuit.
In this system, pulses from a power generator mounted on the motor's rotating shaft are compared with pulses from a crystal oscillator, and the phase difference is detected to maintain the motor rotation speed.
In order to improve the reliability of the circuit itself, we have been making efforts to convert it into an IC. Bipolar ICs are used for the drive circuit and MOS ICs are used for the control circuit.
Since the XL-1550 drive circuit operates in the forward and reverse directions, the motor rotation speed is increased and the electric brake is applied in the reverse direction, enabling quick response.
The strobe is equipped with a waveform shaping circuit. In this circuit, the strobe is turned on after dividing the oscillation frequency (3 mhz band) of the crystal oscillator by a power circuit. This circuit is not affected by the power supply frequency. In addition, by changing the dividing ratio when changing the number of revolutions, adjustment with one stripe is possible.
In addition, the flash current is pulse-lit by a waveform shaping circuit so that the flash inscribed on the turntable periphery can be clearly read.
The servo circuit has a built-in CR oscillator, and the PLL (phase control) works even when the quartz is turned off, so that excellent load resistance and drift characteristics can be obtained even during fine adjustment.
The drive motor uses a high-torque brushless DC servo hole motor with a diameter of 32.4 cm and inertial mass of 340 kg ・ cm.2Rotate the large aluminum die-cast turntable at a constant speed within 2/3 revolutions. The starting torque of this motor is 1kg-cm.
The switching mechanism uses three independently developed Hall elements to achieve high S/N and durability.
S-shaped pipe arm is used for the tone arm.
In addition to reducing the effective mass, this arm uses a high-precision angular contact bearing in the vertical and horizontal rotating parts to reduce friction and obtain high sensitivity.
In addition, a 6t aluminum panel is used for the arm mounting base, and steel plate (thickness 6 mm, weight 700g) is reinforced from the inside of the cabinet to protect the tone arm from howling during ultra-low frequency playback.
The head shell uses a non-resonant type made of aluminum alloy to reduce the weight.
The MM type PC 330 / II cartridge is used.
The cantilever of this cartridge is made of titanium pipe with special heat treatment, and since it is light at 0.45 mg and has little deflection, mechanical impedance is kept low and tracing capability is improved.
The cabinet uses a combination of particle boards.
Equipped with an arm height adjustment mechanism that can be adjusted at a height of ± 5 mm from the reference position.
Equipped with an anti-skating mechanism.
Butyl rubber is used for the turntable seat.
Uses an insulator that combines special rubber and die-cast solid.
The level of this insulator can be adjusted, and it can be changed by 0.5 mm per one rotation of the insulator.
Model Rating
| Type | Quartz PLL Direct Drive Player |
| <Turntable portion> | |
| Motor | Quartz PLL hole motor |
| Drive system | Direct drive |
| Turntable | 32.4 cm Diameter Aluminum Die Cast |
| Turntable inertia mass | 340kg-cm2 |
| Number of revolutions | 33 1/3, 45 rpm |
| Speed change | Electronic |
| Rotational speed fine adjustment range | + / - 6 per cent |
| Uneven rotation | 0.025% or less (WRMS) |
| S/N | 62dB(JIS) 70dB(DIN-B) |
| Load variation | 0% (Needle Pressure 120g or Less) |
| Start-up characteristic | 2/3 turn or less |
| Rotational speed deviation | Not more than 0.003% |
| Temperature drift | 0.00004% / ℃ or less |
| Time drift | 0.0003% / h or less |
| Tone Arm Section | |
| Format | Static balance S-shaped pipe arm |
| Effective arm length | 221mm |
| Overhang | 15.5mm |
| Applicable Cartridge Dead Weight | 4g ~ 14.5g (Sub Weight Over 9.5g is used) |
| Height adjustment range | + / - 5 mm |
| Cartridge Part> | |
| Format | MM Type (PC-330/II) |
| Structure | Shield Case : Super Permalloy Frame : Die Cast Aluminum Alloy |
| Needle tip | 0.5 mil diamond |
| Effective mass of vibration system | 0.45mg |
| Operating needle pressure range | 1.0g ~ 1.8g (1.5g appropriate) |
| Frequency characteristic | 10 Hz to 28 kHz ± 3 dB |
| Channel separation | 25 dB or More (1 kHz) 20 dB or More (100 Hz to 10 kHz) |
| Output voltage | 3 mv (1 khz, 50mm/sec, RMS) |
| Output balance | Within 1 dB (1 kHz) |
| Dynamic Compliance | 12x10cm-6/ dyne (100 Hz, horizontal / vertical) |
| Static Compliance | 18x10cm-6/ dyne (optical) |
| Output impedance | 2k Ω (1 kHz) |
| Load resistance | 30k Ω ~ 250k Ω (Proper 47k Ω + 170 pf) |
| Dead weight | 6.4g |
| Dimensions | Width 14.8x Height 17x Depth 290 mm |
| Mounting Dimensions | JIS and EIA standards |
| Exchange needle | PN-330/II |
| <Others> | |
| Attachment mechanism | Anti-skating mechanism Lateral balancer Needle pressure direct reading weight Arm height adjustment mechanism Arm elevation mechanism Head Shell Stand (Common Use for EP Adapter Receiver) Strobe light lamp Free stop hinge Height Adjustable Insulator |
| Supply voltage | 100 VAC, 50Hz/60Hz |
| Power consumption | 5W |
| External dimensions | Width 490x Height 185x Depth 390 mm |
| Weight | 12kg |