The TT-81 and TT-71 use the same CORE motor. The 81 uses more sophisticated electronic drive than the 71.
Now, the TT-101 is a completely different beast. It uses a CORELESS motor and a "double bi-directional servo" in the electronics. So it is no surprise that Aigenga prefers the 101 over the 81. I have no experience with the 81 nor 101 but I have owned other JVC models and every time I prefer the ones with the coreless motor and even my non-audiophile friends noticed the coreless tables sound "smoother." It has a distinctive fluidity in the sound that's recognizable. I would LOVE to hear a TT-101.
Much information can be found at the invaluable The Vintage Knob site.
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Now, the TT-101 is a completely different beast. It uses a CORELESS motor and a "double bi-directional servo" in the electronics. So it is no surprise that Aigenga prefers the 101 over the 81. I have no experience with the 81 nor 101 but I have owned other JVC models and every time I prefer the ones with the coreless motor and even my non-audiophile friends noticed the coreless tables sound "smoother." It has a distinctive fluidity in the sound that's recognizable. I would LOVE to hear a TT-101.
Much information can be found at the invaluable The Vintage Knob site.
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