Ok guys

Halcro, I have a decibel meter. My SOTA does 18 db down, the SME 25 dB. It has a thicker cover. The difference does decrease a bit with louder volumes. These figures are at 95 dB. Most good  hearing protectors come in at 25 to 30 dB and what are they? A thin plastic shell stuffed with a little foam with a seal fitted. Geoffkait, a Helmholtz resonator requires a throat (opening) Do hearing protectors resonate? Sorry, no mints at all.
I keep meaning to run a test record with a frequency sweep to compare attenuation at different frequencies. I will report when I get it done. Of course I can not be sure what other dust covers will do. Depends on the design. 
 halcro, most house walls are pretty resonant just bang on one. Now go into the next room. What happens to the sound? And the door is probably open. Now close the door. What happens. The dust cover is another room with a closed door. Some miracle ha. 
You guys crack me up. Assumptions are the mother of all ---- ups. If I say the word my post will get deleted. Assumptions based on mythology are fairy tales. 

I love it when he talks about walls, doors and sound......
Almost as if he wasn’t pretending that he had some knowledge of ‘acoustics’ 🤥

Mijostyn, most turntable covers have an opening or gap around the bottom. Thanks for taking the bait.

Mijo, where is your turntable situated with respect to your speakers? In my opinion the best way to cure acoustic feedback, which is what you seem to be talking about, is by careful placement of the turntable in your listening room. And other obvious measures. Not by using a thick or thicker dust cover. If you need a dust cover to prevent acoustic feedback, then you  need to think again  about your room and the equipment in it. By the way, I had to laugh when I saw your comment above that it is we (the no dust cover crowd) who are obsessed with static electric charge. From everything of yours that I have read, it is you who are so obsessed, not the “no cover” aficionados. But in the end, I think we can all agree that everyone should do as he or she pleases. This is not a religion. About your practice in relation to cleaning LPs or your stylus, have you looked at your stylus under a microscope lately? I am wondering what it might look like. I am sure you’ll say it’s immaculate.

thanks for everyone’s input I didn’t intend this to be a question of how much everyone spent on their turntable or entire system, could I spend more on mine yes but when I pulled my 80’s Onkyo turntable out of the garage and my boxes of albums out that I never thought would be cool again too it brought me back and I liked what I heard, I’ve always been in to audio equipment and good sound, so I don’t have a 6 figure system and that’s ok again, could I afford it, yes but I choose to spend my money on my car and my house. Thanks again for your responses