The Kenwood KD-5100 hit the market in 1980 and it’s production run ended around 1982. It’s well built and was higher end for the time but you don’t see them on the market too often. It’s a direct drive, PLL Quartz-locked, fully automatic turntable. The design isn’t bad and the wood hand holds on the sides give it a touch of elegance. The original list price was around $370.
Microprocessor Control System
The KD-5100’s defining feature is its advanced microprocessor-controlled operation, which represents a departure from conventional mechanical systems. The digital-optical sensor system employs LEDs and photo-transistors to control tonearm movement, eliminating mechanical linkages entirely. This design allows for unprecedented operational flexibility – users can manually operate the tonearm even during automatic sequences, and the system allows instantaneous mode changes without risk to the equipment.
Drive System and Speed Control Architecture
The direct-drive system incorporates multiple layers of sophisticated speed control technology:
- A quartz-referenced phase-locked loop (PLL) servo feedback system provides the foundation for speed stability
- The DC direct-drive servo-motor features a slotless, coreless design that eliminates “cogging” (uneven energy delivery)
- A specialized 90-slot precision-cut gear generates highly linear speed control signals
- The sample-and-hold phase detector circuit specifically addresses phase changes that can affect audio quality
- The high-inertia platter (330kg/cm²) acts as a mechanical buffer against transient load fluctuations, which can occur during playback of heavily modulated passages
Tonearm Engineering
The tonearm assembly represents a careful balance of competing design priorities:
- The straight, low-mass design optimizes tracking ability while maintaining structural integrity.
- The carbon-fiber headshell provides excellent rigidity despite its minimal mass.
- The pivot assembly consists of three key components: a pipe holder, pivot ring, and bracket, manufactured from brass and die-cast zinc.
- The holder-to-pivot ring connection uses pressure fitting for better structural stability.
- The entire assembly is engineered to “ride out” warps and resonances while maintaining accurate groove tracking.
Comprehensive Vibration Management
The turntable employs a multi-layered approach to vibration control:
- The base incorporates a synthetic stone structure combining calcium carbonate and glass fiber
- The cabinet design places resonant frequencies below the audible spectrum
- A metal rib creates a rigid connection between the tonearm and motor shaft pivots
- The center shaft features an enlarged diameter and is manufactured from high-quality stainless steel
- The shaft rotates within a brass housing for additional stability
- The anti-skating mechanism uses a nylon thread specifically chosen to block vibration transmission
Operational Features and Safety Systems
The control system incorporates numerous sophisticated features:
- Touch-sensitive electronic controls require minimal pressure for activation
- The record size selector must be engaged before the tonearm will lower
- The system prevents stylus drops when no record is present
- Electronic cueing control can interrupt automatic operation at any position without forcing tonearm return
- Users can switch between full-automatic and manual operation at any point during playback
- The automatic return feature functions independently of the full-automatic mode
Advanced Integration Capabilities
The KD-5100 includes forward-thinking integration features:
- Compatibility with the RC-500 remote control system enables wireless operation
- The remote system can control all automatic operational modes
- Programming capabilities allow for automatic system shutdown after playback
- The touch-key interface provides tactile feedback while maintaining electronic precision
Performance Specifications
The KD-5100 turntable has impressive technical specifications:
Adjustments
Issues
There are some issues with the KD-5100. For one, there is a fuse inside that when blown will result in the table not lighting up or rotating. Basically, it will seem dead. Replace the fuse and, if you’re lucky, the turntable will work. Definitely the first thing to look at.
The hinges are plastic and the metal spring inside can break through the plastic. Sometimes you can find original replacements on eBay and I have also seen some 3D printed replacements floating around. Some users press a metal shim into the hinge to hold the spring in place.
The anti-skate mechanism has a small string that can break and is not easy to fix.
The speed can get sketchy but usually just requires cleaning the pitch control with some contact cleaner.
Keep in mind, that the KD-5100 does not default to standard lp size when powered on. It defaults to 33. You have to select the record size or the arm will just return to the rest & shut off.
While it is a Direct Drive deck there is a small belt that moves the tonearm. It stretches with age causing the arm to set down in the wrong location. You can see the belt here:
Fortunately there are replacements available on eBay.
Reviews
“It’s my favorite of the dozens of turntables that have passed through my hands.”
“I’ve been consistently impressed with this turntable and I think you will love it!”
“Overall the KD-5100 is a pretty rock solid turntable.”
Summary
The Kenwood KD-5100 is a great vintage turntable that gives you excellent sound without breaking the bank. Built like a tank with its direct-drive motor and quartz-locked system, it offers the kind of stability and precision that modern turntables charge a premium for. Plus, its sleek aluminum design looks great in any setup while delivering warm, detailed audio that’ll make your vinyl collection shine.
