Hi Jarek, thanks for the kind words.
Actually the improvement coming from the air suspension was quite considerable. An unsuspended turntable in my experience does gain quite a bit from insulation from external vibrations. And for the TW specifially it brought quite some improvement in regard to imaging, soundstaging and general naturalness and detail of the sound. I can only recommend to experiment a bit with whatever kind of insulation is available.
In my case I followed advice from extensive discussions in the German analog-forum.de where DIY air suspension has been quite a topic some years ago. In the picture below - some 3,5 years old - you can see the RRG pneumatic isolators that I chose for my installation. I chose them over the similar American Fabreeka isolators simply for reasons of availability over here, technically there should be no difference.
Ideally the load for 4 of these air springs should be >120kg to achieve a resonance frequency well below 5 Hz, unfortunately I can only manage around 80kg currently. So the resonance frequency is higher than ideal. Still the effect was quite amazing even with this load.
I can't wait to finally get the BN platter because it will not only add quite a bit of rotational torque but also add roughly 10kg to the loading of the air suspension.
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