ARC Ref 6 plexiglass cover

It will sound better with the cover off anyway. No matter how thick the cover it traps and amplifies vibrations, assuming you don’t have small children I’d remove it

The cover has holes in it, so dust will get in anyway. At least with it off you can see and remove the dust, and if you’re bothered put it back, or another type of cover, when not listening

the metal covers are worse as they resonate in a more problematic range then Perspex, although Perspex has its own sonic signature

btw @tattooedtrackman hope you’re also getting some Herbies dampers. And you might also play with footers for under the preamp as well

Marigo Mystery feet F8 -- two sets given the Ref 40 is a two chassis. I also have a SR Galileo LE power cord.

@lostbears no, I’m waiting on Ron’s latest H series feet and then I’ll let the Fs trickle down to my other components

Yep, the series H are $2k a set, but the upgrades are audible

the key issue with alternative footers on ARC preamps is clearance under the amp. There isn’t much room between the front of the amp and the raised under cover so larger footers will not fit. Putting the footers only on the metal under cover sounds terrible.  In the case of the Marigo you need to have it half on the frame and half on the under cover which is not ideal but works

I misspoke in a prior post. The Ref 40 undercover is always metal and stands proud of the frame, there is no option of a perspex undercover. 

You can can get a lot of the benefit of the Marigo footers by dropping a puck of his material under your existing footers and the cost is a couple of hundred. You can reach Ron at marigoaudio@frontier.com

Adding any other  footers under the existing ARC ones would not be a good idea as the sorbothane in the existing feet will fight the new footer. The one option that would work would be small sub based/platforms under each existing foot. Ron sells a set of these, cost is about $200. I guess you could also try an inverted footer that rises to a point like the Synergistic ones (which I have never liked)

As I said I get it to work with two points of contact on the chassis and one on the undercover (the design of the Marigo mystery feet is such that they end in points which is wher contact is made).

I have also tried bits of material above the footer to bring the chassis and sub cover level but this sounded terrible

By the way is the undercover on the Ref 6 truly plexi? If so all my rules about contacting it are out the window as plexi is so much less rigid than the older metal under covers I have, I’m not sure I’d like any footer contacting plexi

I see, that’s plexi for sure. You can easily remove the existing rubber feet which will give you some more room to play with. The bigger issue may be the rear where there is even less clearance behind the plexi. In all my installs I’ve ended up needing the rear foot to be on the bottom plate not the frame.

All in it may be that a set of four feet that screw into the existing ARC holes may be a better bet. The Nordost sort fut can be purchased with threaded adaptors for example.

Anyway as you can see ARC have still not made any progress from the super basic feet their amps have always come with

Have fun! The Ref 6 should reveal whatever changes you make in feet or platforms.

@audiolabyrinth it’s an interesting question. Clearly plexi sounds better to ARC, ie performs better in resonance terms, than aluminium. Certainly there’s no cosmetic reason to change out the bottom plate for example. However plexi does have its own sonic signature. Applying a small damping device like a Marigo dot could help but given the mesh design there’s no single place to put it that would damp the whole surface I suspect.