Pioneer XL-A700
¥ 79,800 (around 1976)
Commentary
A full auto player with a quartz PLL servo circuit.
Quartz PLL is used for the servo circuit.
In this method, the motor rotation speed is kept constant by comparing the pulses from the ジャネレーター mounted on the motor rotation shaft with the pulses from the reference signal generator and detecting the phase difference (time difference between lead and delay). This enables accurate detection of minute speed changes with long periods, which were considered difficult to detect with conventional methods, and maintains the correct rotation speed at all times. In the quartz PLL method, a crystal is used as the oscillator of the reference signal generator, and a high-precision reference signal is obtained.
The XL-A700 uses an IC circuit to increase the reliability of the circuit itself. Bipolar ICs are used for the drive circuit and MOS ICs are used for the control circuit.
A bi-directional drive circuit is adopted for the drive circuit, and it can operate in both forward and reverse directions, so quick response is possible even when the motor speed increases.
A brushless DC servo hole motor is used as the drive motor.
This motor has high S/N and high durability by applying the functions of three Hall elements developed by Pioneer in the magnetic pole switching process.
The turntable has a diameter of 32.4 cm and an inertial mass of 340kg-cm.2Precision machining turntable has been adopted.
In addition, excellent characteristics have been obtained by using precision processed shafts and bearings.
The strobe light is equipped with a waveform shaping circuit. In this circuit, the oscillation frequency (3 MHz band) of the crystal oscillator is divided by an electronic circuit to light it. This circuit eliminates the adverse effect of fluctuations in the power supply frequency. In addition, when the number of revolutions is switched, the frequency division ratio is changed to enable adjustment in one stripe pattern.
The servo circuit also contains a highly accurate CR oscillator, enabling phase control even when quartz is turned off.
You can also compare records at the same pitch and adjust the pitch of the records to match the pitch of the instrument. When the rotational speed is finely adjusted by 1%, 5.5 stripes flow at 33 1/3rpm and 7.5 stripes flow at 45 rpm in 10 seconds. Since the rotational speed fine adjustment range is ± 6%, it can be adjusted up to about a semitone.
Equipped with a full auto mechanism.
In addition to the motor for driving the turntable, the XL-A700 uses a precision gear motor exclusively for the automatic operation of the arm, so that no load is applied to the rotating system and high reliability and durability are obtained.
The full auto mechanism allows for auto return, auto cut and repeat performance. It also has a quick play function that automatically turns on when the arm is moved onto the record board by hand.
The return detection mechanism of the XL-A700 uses an optical system instead of the conventional mechanical system.
The XL-A700 uses an LED to illuminate the overlapping position of the movable slit, and uses a phototransistor to detect light transmission and light shielding. The XL-A 200 uses a phototransistor to detect the position of the arm.
S-shaped pipe arm is used for the tone arm.
In addition to reducing the effective mass of this arm, an angular contact bearing is used for the vertical and horizontal rotating parts to reduce friction and obtain high sensitivity. In addition, a 6t aluminum panel with sufficient strength is used for the mounting base of the arm, and the inside of the cabinet is reinforced with thick steel plate (6 mm thick, 700g) to protect the tone arm from howling.
MM type cartridge PC 330 / II is used.
This cartridge realizes a light mass vibration system by combining a special heat-treated titanium pipe cantilever, rare-earth cobalt magnet, and special diamond needle. In addition, by adopting a single-end support system, high-frequency mechanical impedance can be kept low, improving sound quality.
In addition, parts such as aluminum stylus knob and aluminum die-cast frame are used to reduce resonance.
In the cabinet, the motor body, full-auto mechanism, tone arm, etc. are firmly fixed to a highly rigid aluminum die-cast frame to obtain high accuracy over a long period of time.
By combining the rigidity of the die-cast frame with a hard plywood with moderate internal loss, howling and resonance are prevented.
Uses a large insulator combining special rubber and die-cast solid.
The level of this insulator can be adjusted (0.5 mm variable per one revolution of the insulator).
Equipped with anti-skating mechanism and arm elevation mechanism.
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Model Rating
| Type | Quartz PLL Direct Drive Full Auto Player |
| <Turntable portion> | |
| Motor | Quartz PLL hole motor |
| Turntable | 32.4 cm Diameter Aluminum Die Cast |
| Turntable inertia mass | 340kg-cm2 |
| Number of revolutions | 33 1/3, 45 rpm |
| Rotational speed fine adjustment range | + / - 6 per cent |
| Uneven rotation | 0.025% or less (WRMS) |
| S/N | 62 dB or More (JIS) 70 dB or more (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 | 237mm |
| Overhang | 15mm |
| Applicable Cartridge Dead Weight | 4g ~ 13.5g (Sub Weight Over 9.0g 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> | |
| Auto mechanism | Full Auto dedicated AC gear motor (manual, Quick Play available) Auto lead in Auto return Autocut Repeat |
| 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 |
| Semiconductor used | Transistor : 9 IC : 4 Diode : 12 pcs Hall element : 3 pieces LED : 1 Photo Transistor : 1 |
| Supply voltage | 100 VAC, 50Hz/60Hz |
| Power consumption | 10W |
| External dimensions | Width 490x Height 200x Depth 390 mm |
| Weight | 13.5kg |