Last
update 10/8/07
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TMPS1: Single Channel Tube Microphone Power Supply: $539
TMPS1 U67, KM54, KM64, U47-EF14, CMV563, M582 The TMPS1 is a single channel power supply that provides filament and plate voltage via a 5 pin gold XLR connector. Each power supply is built custom, wired pin-pin to the original mic. TMPS1-U47/U48-VF14: The TMPS1-U47 is a single-channel-supply specifically designed for a U47 using a VF14. The plate voltage is adjustable from 90 to 110vdc @ 50mA of DC current. Because the amplifier and filament in the U47 are powered from the same voltage, regulation is even more critical. A typical tube mic draws approximately 1mA from the plate supply (i.e. +105 in this case). In contrast, a U47 draws about 40mA. In an unregulated supply, noise is a function of current, the more current, the more noise. Therefore, a passive circuit will inherently be much noisier for the U47/U48, which is why these mics have a low pass filter built inside them, filtering the b+ before it powers the audio circuit. In a traditional supply, there is approximately 1-2vac of ripple on the +105vdc, in our supply it is less then 0.002vac. |
