Shelf for VPI scout


I received the Mapleshade catalogue in the mail the other day and was reading about the claimed benifits of 2" air dried maple shelf for a TT's. my TT sits on a VTI rack of only average quality and has glass shelves. It's not as stable as I'd like as I can push on the rack at the top and it rocks ever so slowly for once or twice before stoping. If I'd have to call it I'd say like 2hz or so. What I'm curious about is Mapleshade says that glass sucks the bass out of a TT, but on a maple shelf this is not so. Why is this?
last_lemming
I read a book on acoustics a long time ago that listed the properties of various woods, drywall, tile, insulation, and many more that I can't recall. Although I can't remember the name of the book I'm sure you could find something similar at your local library. That should give you the long answer to your question, if you want it.

The short answer, different materials have different acoustic properties, right? Glass has a tendency to reflect most direct sound.... depending on it's composition and thickness of course. Hard woods can be quite stiff and if done properly, can give a rich sound when used for an enclosure. Perhaps the maple shelf has the proper thickness and size to reinforce or resonate in a pleasing nature.

I hope I helped shed some light on what going on.....

Andrew
Synesthesia Studios
As a prior owner of a VPI Scout, I wholeheartedly agree that a maple plinth greatly increased the potential of the Scout. I was quite underwhelmed by the Scout when I first purchased it and had it situated on the MDF shelf of my Billy Bags rack. The maple platform transformed the sound for the better. Much more fulsome sound, better bass, more fleshed out tonal density. Never tried it on a hard glass or granite shelf, so I can't offer any perspective on that situation.
Maybe a rega wall shelf with a large enough maple (or other material of your choice) platform on top? You might even be able to try different platform materials since they are separate from the metal shelf...
I use 2" thick Boardsmith built mahogany butcher block cutting boards for my TT's which then are isolated on elastomer pucks made by Vibropod. The whole works is then hung off the walls of my system 2' deep by 4.5' wide alcove. It works pretty well with both a Denon DP-75 DD in a custom plinth, and a VPI HW-19 Mk. IV. The Boardsmith guys are great - they will make a board of any dimension you want out of nearly any species of wood for $200-$300.

You may also want to replace your feet with spikes which set in brass footers made by Herbie's Audio. Killer.
I use Boardsmith 2" thick mahogany butcher block boards under both of my tables - a spring suspended VPI HW-19 Mk. IV belt-drive turntable and a direct suspended Denon DP-75 DD turntable. Boardsmith will make a butcher block to any size and species of wood you want for between $ 200 and $ 300. My blocks sit of five 25# rated elastomer Vibrapods which are, in turn, mounted to a stiff 2x2 frame which is tied to the walls of my equipment alcove. Very solid.

With this setup the VPI is earthquake proof, the Denon less so. It picks up acoustic feedback in the bass, but only at VERY load levels. Pierre Sprey (Mapleshade owner) is a pretty astute dude - I think there definitely is a benefit to 2" solid platforms for most TTs. Maple is a good species, but probably not unique.

Pierre also knows his way around fighter aircraft design - one of the best minds in the business - we could use him back in the aerospace business today.