Kenwood KD-5077

Kenwood KD-5077 Turntable

The Kenwood KD-5077 was a high-quality automatic direct drive turntable released in 1978 alongside the nearly identical KD-5070 model. As a 2-speed fully automatic turntable, the KD-5077 allowed both 33 and 45 rpm records to be cued and played automatically at the touch of a button. The key difference from the KD-5070 was the KD-5077’s wooden plinth construction versus the compression molded anti-resonance base of its sibling model. With its simulated wood grain finish and added internal weight block, the KD-5077 delivered the same excellent performance as the KD-5070 but with a more traditional hi-fi turntable aesthetic. Both were priced in the $260 to $285 range when new.

Kenwood KD-5077 Platter

Direct Drive

The KD-5077 uses a high quality direct drive design to spin the platter. Direct drive turntables connect the platter directly to the motor shaft rather than using belts or gears. This eliminates the rumble and speed variations that can be caused by those intermediary components.

The direct drive system turns the platter at exactly 33 or 45 rpm, matching the record speed precisely. Rumble noise from the KD-5077 motor is inaudible, measuring -73 dB which is extremely low.

Kenwood engineered the KD-5077 direct drive for optimal performance and stability over time. The center shaft is hardened steel entirely encased in brass with a tempered copper ball bearing. This creates a super rigid structure that minimizes distortion while keeping smooth friction-free rotation.

Many turntables can have problems with unstable or deteriorating shafts. But the KD-5077’s integrated precision shaft ensures consistent playback quality throughout the life of the turntable. So the direct drive design provides rumble-free speed accuracy and long-term reliability.

Features

The Kenwood KD-5077 turntable offers high-end features to deliver exceptional audio performance and playback accuracy. One key feature is the anti-skating control that balances the tonearm’s horizontal force to prevent uneven groove wear and distortion in the stereo image.

Tracking force is adjustable with a direct-readout method for precise stylus pressure. Independent pitch controls for each speed let you fine tune for perfect 33 or 45 rpm playback.

The viscous-damped cueing device uses a specialized silicone oil that is impervious to temperature and humidity changes. This creates smooth tonearm operation in both directions without bouncing.

Kenwood KD-5077 Dustcover

A strobe mirror with illuminated platter markings allows easy speed checks during play. The sturdy acrylic dust cover has strengthening ribs to prevent acoustic feedback.

Finally, low capacitance phono cables ensure the turntable can reproduce all the extended range material on quadraphonic CD-4 vinyl records.

Kenwood KD-5077 Strobe

Tonearm

The S-shaped tonearm on the KD-5077 is carefully engineered to minimize distortion and resonance. Tonearm design has to balance several factors. It needs to be light enough to accurately track the record grooves, but not so light that it is unstable. It also needs to be rigid so it doesn’t shake, but not so heavy that it loses high frequency sounds.

The S-shape helps reduce tracking error, which is distortion from the angle of the tonearm. The KD-5077 tonearm is light and responsive, but also rigid enough to avoid shaking.

There are a few elements to the KD-5077 that reduce resonance, which can add vibration distortions. First, the counterweight that balances the tonearm is isolated from the arm with rubber, preventing its vibrations from reaching the stylus. Second, the wide tonearm base increases overall rigidity and stability.

Finally, the headshell is made from a thick, rigid aluminum alloy which pushes any resonance out of the audible frequency range. Together, these engineering details allow the tonearm to precisely track the record grooves and produce clean, accurate sound.

Kenwood KD-5077 Tonearm

The KD-5077 has a separate motor just for the automatic tonearm operation. Most automatic turntables use the main motor to also move the tonearm. But this can put extra strain on the main motor and cause fluctuations in speed called “wow and flutter.”

The KD-5077 avoids this by having a dedicated synchronous motor with 12 poles solely to drive the tonearm mechanism. This allows smooth, quiet operation for automatic cueing, returning, and repeat playing. There is no added wear on the main motor or variation in turntable speed.

You can also move the tonearm manually. A safety device stops the automatic operation if you touch the arm when it is in motion.

The controls are laid out in a logical way for easy use. The start button only requires a light touch to activate the automatic tonearm or start the turntable spinning. So the separate motor provides reliable automation without compromising audio performance.

Kenwood KD-5077 Cross Section

Plinth

The base of the KD-5077 turntable is made of three different materials – resin-concrete, acoustic particle board, and rubber. Each material helps prevent “howling” or feedback sounds in different ways.

Resin-concrete is very dense and heavy. It absorbs low frequency vibrations that could cause howling. The heavy motor is mounted on the resin-concrete to distribute its weight evenly.

Acoustic particle board is a special high density board that absorbs vibrations in the high frequency range that could also cause feedback.

Rubber feet under the base absorb any remaining vibrations across all frequencies that might cause howling sounds.

Together, these three materials in the base prevent acoustic feedback at any frequency, which allows the turntable to produce clear, clean sound without distortion.

Kenwood KD-5077 Counter Weight

Specifications

Here are the specifications for the Kenwood KD-5077.

Kenwood KD-5077 Specifications

Motor

The Kenwood KD-5077 turntable has a specialized high-torque DC motor to spin the heavy platter and maintain very consistent speed. Direct drive turntables need powerful motors to get the platter spinning and keep it at the right speed.

Kenwood designed a new 20-pole, 30-slot brushless DC motor for the KD-5077. It produces 900 grams of starting torque, which is very high. This gives it the power to spin the heavy platter.

Kenwood KD-5077 Motor Belt

Brushless DC motors can have uneven torque caused by switching currents. More slots in the motor help minimize this issue called “cogging.” The 30 slots in this motor virtually eliminate cogging.

The combination of high torque and minimal cogging allows the motor to achieve 0.025% wow and flutter. That’s the tiny speed variations as the platter spins.

In addition, an electronic servo circuit monitors the actual motor speed and makes micro-adjustments to maintain correct 33 or 45 rpm. This further reduces wow and flutter below 0.02%.

Kenwood KD-5077 Hinges

The Kenwood KD-5077 turntable is a reliable performer. Its specs are good and it has nice styling. Some prefer the resin base on the KD-5070 but both look good. The KD-5070 is a little more common than the KD-5077 so was probably a better seller. You can’t really go wrong with either one

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