KAB PS-1200GX

   KAB began its relationship with the 1200 in 1994 with our Broadcast Standard version which featured 78 rpm. We were the first to introduce the 1200 to audiophiles, when we added the TD-1200 tonearm fluid damping system in 2000. We introduced the very first outboard regulated power supply for the SL1200 in 2003. The PS-1200GX is our latest design to address the entire power system of the Technics SL-1200/1210 MK2,3,5,6 and M5G series turntables.

    The PS-1200GX provides a very clean, quiet DC voltage. It eliminates three sources of sonic contamination: The electromagnetic field and mechanical vibration of the internal transformer; and the large peak-to-peak ripple voltage of the internal power supply. It is a complete system consisting of an efficient power conditioner, updated internal regulator(DC-1200) and strobe lamp on-off switch(SX-1200). We never stop improving; The PS-1200GX is our latest solution to the entire power supply system and it sells for less than half the cost of old fashioned alternatives.

Since the PS-1200GX is external and no low frequency transformers of any kind are used, all original sources of mechanical vibration and low frequency EMF are eliminated. The 'table plays quieter. Sonically this enhances low level resolution and intertransient silence. The PS1200GX can be located close to the turntable without fear of hum fields radiating into the cartridge. This cannot be said for many of the overpriced old fashioned alternatives out there which house conventional unshielded low frequency power transformers in non ferrous aluminum boxes. Pretty as they are, these designs actually radiate more low frequency EMF into your listening space than the stock original internal transformer! Over 10 years old, many of them, those old fasioned designs are now, in our opinion simply overpriced, worrisome and technically out of date.

    The KAB PS-1200GX meets the latest standards regarding power supply efficiency. It is a green design that consumes less than 0.5 watt in standby mode. It works in any country, on all standard line voltages.

Note: Installation of this product requires basic electronic skills. Tools required are philips screwdriver, small flat blade screwdriver and wire strippers. Soldering is required for SX-1200 board. Only for Technics SL-1200/1210 MK2,3,5,6 and M5G series turntables. SENSE feature requires north american power plug..

Only $289

SPECIFICATIONS

• 28V Regulated Output Voltage
• Choke Input Filter
• 4 x 1000 uF Reservoir Capacitor
• DC Supply Line Noise: < 200uV(10-100Khz)
  
• True Over Voltage Protection With Full Relay Disconnect.
• SENSE Line For Power Switch Detection
• Weight: 2.75 Lb.
• Dimensions : 4.2" X 4.9" X1.7"
• Owners Manual

    The 1200 original power supply has very little reservoir capacitance, 470 uF. The bulk of the supply filtering is performed by the DC regulator, doubling as a capacitance multiplier. These circuits are common, but they are not optimum. The PS1200GX system replaces the internal regulator with our updated DC-1200

   By incorporating a two stage choke filter and 4000uF capacitor, the DC leading into the 1200 is now a clean source of power. This lets the internal regulator do a better job of regulating the motor load.

Also, since the internal power transformer, is deactivated, an additional source of EMI and mechanical vibration is eliminated. The turntable plays quieter.

    The PS-1200GX uses no low frequency transformers of any kind, eliminating all sources of low frequency EMF. The kind that can cause audible hum.

Both DC-1200 and SX-1200 are included in our complete power supply system, the PS1200GX. As a complete system, the PS1200GX reigns a tight control over the power distribution within your 1200 assuring the best possible performance.

• 1 Year Warranty
• Totally Green Design
• SENSE Line For Power On-Off
• 120V- 240V Operation
• Meets all International Regs.

   To gain international approvals, I wanted to use a high quality switching power supply as the front end of the new design. Switchers are economical, fully certified and very light weight. The only purpose of the switcher is to provide a wide range of AC voltage input 96-240VAC and to output a fully regulated 28 VDC input to the DC conditioner. The DC power conditioner is a 2 stage choke capacitor filter network. Using ferrite chokes, we are able to filter the remaining high frequecies from the switcher and leave with a very clean DC voltage. There is also an overvoltage protection circuit for added security.

Since the PS-1200GX is external and no low frequency transformers of any kind are used, all original sources of mechanical vibration and low frequency EMF are eliminated. The 'table plays quieter. Sonically this enhances low level resolution and intertransient silence.

    The SENSE line detects the original power switch in the turntable. This way you turn the PS1200GX on and off just by using the original power switch. This feature requires your 1200 to have a north american power plug.

Notes On Power Supply Design

If you are planning on building your own power supply, here are some hints.

1. Be sure to keep one regulator close to the motor circuit board. Some designs locate the only regulator with the AC components in a separate chassi and then connect with a cord. The inductance of just 2 feet of wire will defeat the hi frequency performance of the regulator and could cause all sorts of noise problems deep inside the table. Or consider a 3 wire design with a load sensing return line to cancel the effects of the cable.
   
2. Never use a non ferrous chassi. Using an aluminum chassis lets the EMF from the power transformer bleed right through. A toroid transformer will radiate up to 20 Miligauss. A steel chassis reduces that to below 7mG, aluminum however lets all 20mG pass right through. If you must use an aluminum box either internally shield the transformer or, mount the PS at least 1-2 feet from the turntable.
   
3. Batteries are not the most quiet source of power and they do not have good internal impedance properties. Further the impedance rises as they discharge. If you want to try batteries, you can follow them with the PS1200GX. that gives extreme filtering, and the ablility to use the "sense " line for controlling power.