Are Dust Covers a MUST

need some opinions on weather or not to keep the dust cover on my mmf5 TT?

pro and cons?

Thank you
I use a dust cover on my Immedia turntable for two reasons: to keep dust off, and perhaps more importantly, to keep people's hands off.
Dust covers not only keep the dust out but also keep wandering hands away. Many of my customers regretted not having a dust cover on when they lost an expensive stylus to cleaning ladies, kids, pets, or even their own loose sweaters.
I don't recommend keeping the dust cover on when playing, however, as its resonance will screw up the sound (the cartridge picks it up).
Disclaimer: I sell dust covers.
Vinh Vu
Gingko Audio
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I think you are asking if one should leave the dust cover on during play or not. I have owned a MMF 7 in the past and never liked the sound with the dust cover on, flipped up or not. The MMF 7 had hinges that allowed for easy lift off of the dust cover. I'd remove it while the table was in use and replace it when I was done.

IMO, it is not a must have for maximum vinyl enjoyment. However, as others have posted there are many excellent reasons to have one. Currently I have no issues with hands of any kind and I haven't had a dust cover for several years. I do carefully use swiffers and microfiber cloths pretty regularly.
I use a silk scarf to keep the dust off of my TT.

Visitors are carefully manacled and their children are leashed. No problems so far.
I have a Gingko dust cover on my VPI Superscout/rim drive and with it on, it looks like a museum piece. Company always gravitates to the turntable with smiles. The unit is very well made - fits perfectly, and is beautiful to look at.
A Linn dealer (warning warning) once told me that the dust cover blocked vibrations for ambient sound waves and thus helped isolate the cartridge.

Sounds counterintuitive to me, always did.
i had a vpi hrx which i bought a dust cover for. the only time i used the cover was when i did not use the tt for a long period of time. although i did not always no when that would be. other then that it sat on the floor and was something else to keep clean. i actually came close to damaging my tt while removing the dust cover a few times. to me a non-must!
I'm in the blocks airborne vibrations camp. Maybe it all depends where you keep the table in relation to that crep you're playing too loud, haha.
intuitively i would think the dust cover acts like a microphone and receives air borne vibrations. it would requite some pretty fancy vibrational analysis to design a dust cover that attenuates or drains vibration. which is in itself a tricky subject in that if you drain too much,... the music becomes lifeless.
Dustcovers that remain attached to the table usually do affect the sound detrimentally, whether played with the cover up or down. I have one that fits over my Basis table, so it must be removed completely to put on a record. I no longer use it at all because of the incovenience.

To keep the platter from collecting dust (which would then contaminate a record), I use a "sacrificial" record as a platter dust cover (a Charlie Rich record someone gave me). The rest of the table gets dusty, but, that can be cleaned off occasionally. When I was actually using the cover, a lot of dust still managed to collect on the platter, so, the record-as-dust-cover was still a good way to reduce dust build up.

I use a microfiber dustcloth to wipe down the platter once in a while. I keep the platter very clean because my table uses a vacuum clamp that firmly pulls the record surface into contact with the platter surface.
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It keeps the kids and the cats away from my Allaerts cart!

I have a large removable dust cover for my Platine Verdier. Great investment for 300 bucks (GBP200). It keeps my kids, our 5 cats and more importantly our cleaner away from my valuable Allaerts cartridge.

Chasmal et al.:
We mounted a B&K accelerometer on the plinth and/or platter and compare vibration with and without the dust cover while playing different frequencies through the system.
Vibration is much more with the dust cover on. How it translates into better sound depends on your system and your ear. If the listener cannot tell the difference then it should not matter to him/her.
I cannot see how a cover can "block" vibration. Being a hard material, it not only transmits the vibration but also resonates at its own frequency as a result. That should add to the overall vibration, not reduce it.
A cover can block vibration because it acts like a fence (think Faraday cage but for airborne radiation instead of electromagnetic) between the excitement in the surrounding air and the tonearm. Consider, can the neighbors hear your rig better with the window open or closed? The chassis itself is necessarily exposed to the environment and hence the damped plinth. To stretch the idea even further the cover typically damped by felt pads above the chassis may act to soften chassis induced vibration similar in effect to the mass loading of component cases.
Faraday cage?1?! Not even close to a good analogy. Listen to Vu, he knows what he's talking about.
Concur with Vtvu. Having a dust cover is probably going to make the system sound worse. ime, I tried using Cardas RCA covers and they noticeably imparted a metallic signature to cymbals that was not there when they were removed. The only issue was that they decreased the noise floor significantly so I went looking for replacements. I've recently picked up the Acoustic Revive units which I hope won't have the same drawbacks but will have the noise floor benefits.
Yeah Dan but it was a toss up between that and the Cone of Silence in the chief of Control's office from Get Smart.
Which dustcover would be better if it has to be used?
One sits on the plinth or one sits on the rack that the turntable sits on? If the latter is better, why there is not many companies that make it?
After much experimentation (this afternoon) I think I like it better OFF. It seems to have a bit more air.

Whether it is all in mind or not is...the eternal question.
We make both plinth top and table top covers. Plinth top sits on the plinth and table top sits on the "table" or rack shelf.
If you don't mind the larger size, table top protects the TT better, and people like the fact that it is like a museum case over their fancy looking TT. Plinth top has the advantage of being smaller, hence easier to handle. The best cover is the one you will use, just like the best camera is the one you will use. I used to own a fancy Nikon, but found that I carry my Panasonic Lumix in my pocket everywhere, and thus using it the most.
So some prefer plinth top, as it is easy to lift and replace.
In any case, take the cover OFF when you play records. The higher resolution your system is capable of, the easier it is to tell the positive effect.
The higher resolution your system is capable of, the easier it is to tell the positive effect.

Vtvu, do you have a website or link to your products?
I know Ginko makes dust covers, costing $250+. There is one audiogon seller selling it at $175+.
I just use a plastic printer cover over the whole TT when not in use, to keep the dust off. I think it was $3.99 on e-bay, for 2 (so I have a spare if this one rips in a couple of years - ha!).

I like dust cover primarily for protection from Dust, prying hands or accidents.
As far as sound with the dust cover on,in my experience, it definitely changes the sound towards warmer side. If you had edge before, it would likely go away. If you had warm sound, it would change to warmer. It is almost like you changed your phono cable

Which one is right? The one you like!

I like it with cover on.
i fabricated a sliding cover for my turntable. the cover slides on rails attached to my 5 or 600lb rack. the turntable sits on a HRS M3 isolation platform which sits on a spiked shelf. the cover is usually open while playing but gets closed when there are people (including my 4yr old daughter) around. there is no impact to sound open or closed. you can see pics in my system.
The dust cover creats a resonant cavity. Always try the TT with and without the cover to see which sounds better.

"I like it with cover on"

I should add, 'thus far'. As I am still experimenting. I just got cover (custom shape) made and delivered on Christmas Eve. BTW my cover rests on TT plinth/stand. May be the cover acts as acoustic receiver and adds/impacts to the TT's vibration control (system).
I'm sure Gingko products are top quality but charging $300 for a piece of acrylic is absurd. Got mine custom made for $75 including cutouts for the tonearm that protrudes beyond the plinth of my Scout slightly when resting. The shop owner told me there is absolutely no good reason why an acrylic dustcover should cost $300. No kidding.
I've heard both side of the argument but I can't get past the mental image of a vortex of dust particles raining down on my albums. Dust cover on and down when I'm playing LPs.
I am coming very late to the party here, but the guys that make these products have to pay employees, pay the light bills and pay the rent plus buy the raw materials, shop supplies and pay equipment depreciation & transporation cost plus make a profit...I think a professionally made at $300.00 dust cover from Gingko is a steal..

I just ordered a custom Cloud 11 and I think it is quite a bargain compared to many of the $$$$ overly inflated and often ineffective products out there..My 2 cents
Until someone does a double-blind abx test to prove otherwise, dust covers do not detract from the looks of any turntable. That's my story and I'm sticking to it.
Everybody I know who tried going commando (no TT dust cover) was dead inside a week.

I have the same problem with dust in my home, and don't like the idea of having to take my martin logan panels apart to wash them down. I got a pair of custom made anti static dust covers, I think they will be a life saver for me. Anyway, just wanted to share this with the forum. Here is the link is anyone else is interested
Platter covers are more of a 'must' IMO to keep it clean and prevent dirt transfer to LP's. I've been using a platter sized cartridge alignment protractor that came with an old test LP record and recently replaced it with a poly platter dust cover from
Get a decent room air purifier. Hel-looo! I'm using one that's like those the US Navy uses on submarines, so they say.
A dust cover when not playing music is a must.

No dust cover during playback.

A dust cover during play, is an acoustic feedback pickup, from the sound coming off the speakers.
  Always removed the cover from the LP-12 when listening.  Never tried it with it on.
  Bought a new ’table that didn’t come with a cover.  Ordered one from J Display case.  Much cheaper than Gingko.  Need one to keep the dust off.  Thought about just a cloth, or silk cover, but that look I care not for.
I have a turntable with a dustcover. If you saw the dust that accumulates on my dustcover, you wouldn't be asking whether they're necessary, but where to buy one.

I guess you could cut a rectangle of shower curtain and drape it on the record player when you're not using it.
I use quality fabric from the fabric store

also pick up gently from the back
place back on front first

no pets or young kids (22 year old knows better)
Don't use a dust cover...too big and klutzy to fool with every time I want to play a record.  I use a microfiber duster to remove the offenders and am good to go.