U-Turn Audio Pluto Phono Preamp Overview
Sound systems have evolved in the digital age. Where there once was always a receiver or integrated amplifier designed to handle multiple sources – and that always included a turntable/cartridge combination – today there may be a direct or wireless connection to powered speakers, or a digital amp that just handles computer and mobile files. To add the warmth and realism of vinyl to such systems, you need a phono preamplifier such as U-Turn’s Pluto. Sturdy construction and high-quality circuitry adds the proper equalization and boosts the signal from any turntable and moving-magnet cartridge – including, of course, U-Turn’s own audiophile Orbit series – to feed the line-level analog inputs of devices including receivers, headphone amps, DAC boxes and powered speakers. Inexpensive, impeccably engineered and sonically top-notch, the Pluto paired with a turntable can add a vinyl touch to your 21st-century setup.
- - Simple, direct circuit design for lowest noise and distortion
- - Precision components for clean signal amplification
- - Accurate RIAA equalization (+/-0.2 dB from 20 Hz to 20 kHz)
- - Subsonic filter reduces turntable rumble
- - Steel enclosure for strength and shielding
- - Weight: 0.9 lbs.
- - Dimensions: 5.8” wide by 1.6” high by 3.6” deep
So, why a phono preamp?
Think about the physics of a record and a record player. A tiny needle wiggles in microscopic grooves, which in turn waggles equally tiny magnets and coils, to turn those movements to music. Without further electronic augmentation, turntables generally generate a low voltage signal. A separate piece of equipment in your sound system must have inputs specifically labeled “phono” to handle such low-level signals, or they won’t be powerful enough to drive an amplifier’s “line-level” inputs and, through that, your speakers.
Explaining the RIAA curve
The second job of a phono preamp refers to how vinyl records are made. Unlike most sound sources, which strive for flat frequency response, records are equalized before the production process with an industry standard designed to reduce the hiss, pops and clicks of vinyl (and, not incidentally, to fit more music on a “long-playing” LP). The phono preamplifier must accurately apply mirror-image equalization to deliver the wide, flat final frequency response we’ve come to love.
Let’s get ready to (not) rumble
The Pluto carries off its two tasks admirably – and then some. The simple, direct circuit design uses top-quality components such as WIMA film capacitors and precision resistors, for accurate reproduction and long life. A single gain stage reduces harmonic distortion. A built-in subsonic filter helps eliminate the low-frequency “rumble” typical to many turntables. And an enclosure made of high-quality steel shields the low-level signals inside from interference outside.
At a low price, the Pluto allows you to add a turntable/cartridge combination to virtually any sound setup. A wired system with analog “auxiliary” inputs make a perfect home for the Orbit/Pluto combination.
- - Input impedance: 47kΩ
- - nput capacitance: 100pF
- - Gain: 36dB @ 1kHz
- - THD: < 0.005% (A-weighted)
- - S/N ratio: - 90dBA
- - RIAA accuracy: +/- 0.2dB (20Hz - 20kHz)
- - Dimensions: 5.8" x 1.6" x 3.6"
- - Weight: 0.9 lbs.