I stack my Innersound preamp and phone stage (they are both slim and light and exact sizes). Roger Sanders said they were designed to be stacked (he used to own Innersound-the electronics are made by Coda). I had them stacked for years but recenlty (3 months or so ago) I placed symposium fat pads between them (I always had them under the lower component). It did make a very nice change in sound (more detail, less phono noise, wider phone soundstage, seems to have tightened up phono base and widened soundstage on all sources). I wouldn't stack anything over a CD player. I have had some CD players, in the past, stop working due to weight issues on the player. I do have my squeezebox on top of my Benchmark (SB is very light) and have had nice improvement since I put squeezebox on a symposium svelt shelf and vibrapod disc under SB. My suggestion is perhaps ok to stack light gear but use isolation devices.
Advice on stacking equipment
In a possible space saving and redisplaying exercise Im thinking of stacking my line stage ( see system for details) on top of my cd player.To be honest I'm in two minds regarding the audible benefits of isolating/coupling equipment. But like most of us I I've bought over the years a number of aftermarket accessories in the pursuit of improved performance . At present I have a 1" thick sheet of black delrin under my klyne pre. one set of black diamond cones and 3 DH squares under my cd player along with some (12) small medium hard rubber like feet brought and recommended to me in by a high end dealer in England in the early 90s . I'm wondering what other members have used with good results when having to stacked equipment. Or is it always a bad idea? Thanks.