I've recently ordered a Clearaudio synchro to address this problem but you might want to also check into the other various speed controllers which are available, such as the Project Speed Box or Speed Box SE;
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"This tiny black box allows painless speed change between 33 and 45 rpm with the mere push of a button. But that's not all. This neat little box offers quartz-generated electronic speed regulation. In other words, the Speed Box isolates the attached turntable from line voltage fluctuations that can affect speed stability. The quartz oscillator boasts a speed stability of +/- .01%. The more upscale Speed Box SE offers speed stability ten times better than the Speed Box. If you think a fraction of a percent of speed variation wouldn't have much of an audible affect, you should hear what the diminutive Speed Box can do. I'll get to it later but it literally blew me away. I truly did not expect the degree of sonic mprovements that this little CDN$129 box delivered."
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6moons Speed Box review
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"This tiny black box allows painless speed change between 33 and 45 rpm with the mere push of a button. But that's not all. This neat little box offers quartz-generated electronic speed regulation. In other words, the Speed Box isolates the attached turntable from line voltage fluctuations that can affect speed stability. The quartz oscillator boasts a speed stability of +/- .01%. The more upscale Speed Box SE offers speed stability ten times better than the Speed Box. If you think a fraction of a percent of speed variation wouldn't have much of an audible affect, you should hear what the diminutive Speed Box can do. I'll get to it later but it literally blew me away. I truly did not expect the degree of sonic mprovements that this little CDN$129 box delivered."
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6moons Speed Box review
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