![]() |
Tweakers' Asylum Tweaks for systems, rooms and Do It Yourself (DIY) help. FAQ. |
|
In Reply to: RE: Shelves are trouble. posted by hatari on August 27, 2007 at 11:39:12:
As someone who has gone shelfless for several years, made a number of constrained layer shelves of various constructions and played with them and a variety of footers, and finally gone the commercial route and bought a Grand Prix Audio Monaco 2 shelf unit with their composite shelves, I think I can make a few comments.Going shelfless does simplifiy a lot of things and can work extremely well, but you end up with the problem of what you put between the component and your support bars. I discovered that you can experiment endlessly there and spend a lot of money into the bargain.
If you have to have shelves and you're going to go DIY, my preference would probably be for one of 2 things. My first option would be a constrained layer construction with either ply or mdy outer layers and an inner layer of GatorBoard. It will support a lot of mass, it's relatively neutral, and it's reasonably effective. You can play around with a variety of footers between the component and the shelf and get some variations on the sound and effectiveness but just on its own such a construction will work well and give good results. If you want to go cheaper and not quite as effective, you can replace the GatorBoard with polystyrene but be carefull with your glues because some glues will dissolve polystyrene. White PVA woodworking glue works well and can be used without detriment to the polystyrene. If you need to dress such a construction up for appearances sake, you can make the top board slightly larger than the bottom board and GatorBoard, veneer the top and add veneer strips around the side that descent level with the bottom of the construction but don't contact the sides of the bottom 2 layers.
You can use other constructions and acrylic makes good outer layers but is expensive. My best results for an inner layer have been GatorBoard with dense polystyrene coming second.
One thing to remember about constrained layer constructions is that you don't want contact between layers anywhere but at the glue intersection between one layer and the next. Don't bolt through one, or use decorative sides that contact more than one layer.
There are now some vibration absorbing glues around that could be worth trying. They weren't available when I was experimenting with these shelves but if I were playing with them these days, I'd definitely give those glues a try.
My second option is, strangely, a shelf of balsa wood. I've only experimented briefly with this and it does seem effective. The wood is soft and probably won't support much mass unless you laminate it in several layers and you're probably going to have to do some lamination anyway because of the sizes you buy it in. You're probably going to need to consider shelves about 3/4 of an inch thick for strength, and you aren't going to be able to use cones between it and the component unless you use them point up because point down they'll simply sink into the balsa and damage it.
Regardless of which of the above options you try—if you try one—you don't want to fix it firmly to the rack frame. You need to support it on the frame somehow, whether you use cones, ball bearings, some of the footers from Herbie's Audio Lab, or whatever.
I'd strongly prefer either of the above options over solid timber but that's my personal taste and others have strong tastes for solid timber.
If you have the time and money to play a little first, I'd assemble a constrained layer shelf, perhaps a balsa shelf, and a solid timber one and try some A/B comparisons to see just what the effects of each were in my system and how they matched up to my tastes.
David Aiken
Edits: 08/29/07
This post is made possible by the generous support of people like you and our sponsors:
Follow Ups
- RE: Shelves are trouble. - David Aiken 22:59:40 08/29/07 (0)