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In developing a new turntable, there was one law that was quickly learned. Everything matters! Everything. That is why we took great care in every detail of the KODO turntable. Many details can be seen, even more can not. They all can be heard.
Building a turntable that can turn a platter at a constant speed seems at first glance, a simple task. After listening to many many turntables, it is obvious that such is not the case. Eliminating drive slippage is next to impossible on one drive method and noise is a major issue on another drive topology. Cogging or motor pulsations are the bane of the third major form of turntable propulsion. After studying all the main drive systems for turntables and a few not so common, my conclusion was that a form of direct drive offered the most potential advantages. Quiet, low RPM motor, very low air turbulence, by far the least amount of moving parts and hence, the least amount of drive train losses which equals less noise. In other words. more of the power going into the table is used to drive the platter and there will be less extraneous energy floating around that needs to be contained. When one understands that the cartridge is really just measuring the size of the grooves in the record and how small these grooves can be, we can understand maintaining speed is of the utmost importance. It follows that keeping outside vibrations or energy from getting to the record is also of major importance. The smallest variation in speed or external vibrational energy from the drive system will impart itself as a loss in clarity and smoothness of the music. This is easily noticeable on sustained piano notes.
Finding a drive motor that exhibits extremely low vibration and magnetic drive pulsations is not an easy task. Single phase AC motors display very strong pulses making these common motors unacceptable. DC motors are much smoother, relatively inexpensive and used in many turntables. The issue with DC motors is that their speed is affected by the load. That means they need a control circuit. The control circuit can make the average speed almost perfect but this is achieved by constant speed adjustments so there will be constant small speed variations. Many high end tables have used extra mass in the driven rotational mass (platter) to help hide the speed corrections. All this really does is put a Band-Aid on the problem, not fix it. Extremely heavy platters tend to make the music sound slow and lethargic. No amount mass will stop speed variations from an improper drive source, unless of course, it is so heavy it will not rotate at all! All compromises that the KODO was not prepared to accept.
The answer came in the form of a 3 phase true synchronous motor. What makes this motor the best choice for a turntable is that its speed is not affected by load changes such as stylus drag and bearing oil temp. When the load changes, such as stylus drag in complex music passages, a synchronous motor instantly draws more current and supplies more torque to the platter. This makes the controversial matter of stylus drag a non issue. Because of this behavior, this type of motor does not need any form of servo circuit to control the speed when fed the proper power. This power is supplied via a sophisticated and very accurate power supply designed to give KODO clean and consistent power of the correct frequency, no matter how dirty your mains supply. This power supply also gives the audiophile another innovation, adjustable motor torque. Every listener seems to enjoy a slightly different take on his music so KODO lets you adjust the strength of the drive system. Want more of a Koetsu sound...dial the torque back and dynamics become softer. Want more impact and energy from your music? Turn up the torque and that leading edge energy from the kick drum, pluck of a string bass or piano becomes more intense. This is one area where the designer can't make everyone happy so KODO lets you decide on the energy level and smoothness delivered from your vinyl source.
Some cultures say the Devil is in the details. Others say God lives in the details. In any case, the details have won. There are many many more details such as platter and plinth development, plinth materials, armboard isolation, armboard material, footers etc. For example, the shape of the plinth is such that it reflects room energy so the record grooves are the only thing moving the stylus.
Let's face it, all that matters is...how does it sound? We invite you to hear for yourself.
Dimensions:
Two arm plinth 21.5"w x 16"d x 7.7"h (570 mm x 410 mm x 200 mm)
Weight:
Platter 25.5 lbs (11.6 Kg) precisely balanced
The KODO platter uses a unique blend of copper, multilayered polymers and brass.
two arm table 99 pounds
Motor:
Extremely low cogging 3 phase true synchronous motor with advanced precision power supply
Max start up motor torque 35 lb-in torque (40 kg-cm) adjustable via the power supply to suit individual tastes and environments
Speeds, 33.33, 45 and 78 RPM
Bearing:
Proven one inch stainless steel shaft riding in an extra long brass housing. Precision machining tolerances better than 5 ten thousands resulting in an extremely quiet bearing.
Shaft is polished with a 10 micron or better finish.
Custom long life synthetic lubrication is used. Temperature changes have essentially have no affect on the viscosity for consistent sound.
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