Isolation?


I've been reading through a bunch of threads here on isolation material/techniques. Fascinating, some of the tweakers here go to great lengths. Kudos gents. My preamp, CDP, turntable, and tuner are all sitting on a custom made solid oak rack. High WAF. Anyway, put marble under my Oracle turntable, Brightstar boxes under my YBA CDP and Magnum Dynalab tuner. Stock feet under my Martin Logan Quests Z's, placement and kids dictate it's not practical to put spikes under them. I just finished building an amp stand (it sits in my furnace room, below the speakers). I used 4X4 lumber for the frame of the amp stand, the lumber sitting on a cement floor, and for the shelf I made a sandwich. The two outside layers are 3/4" BC Fir Plywood. In the middle is 3/4" rubber. I bought a heavy duty rubber mat normally used to leave yer shoes on, smooth on one side and ribbed on the other; I used contact cement to glue the ribbed side to the plywood attached to the 4X4 lumber, then glued the smooth side to the top piece of plywood. Countersunk 4" long screws to attached the whole thing together. My BAT VK500 sits on top of this sandwich. I was also considering using Tiptoes under the amp, but I'm undecided. First off, Tiptoes are a real pain in the ass to install unless you use two-sided tape and you may end up losing any of the sonic benefits of the points with tape in the way. Secondly, does it make sense to drain energy into my "sandwich" or just allow the current base to do it's thing? Finally, am I getting carried away (again)? Does isolation make a big difference with amps, or more so with source and speakers? Jeff

p.s. amp stand cost me $40 in materials
jeffloistarca
Jeff, one of these days soon the temperature up your way will get high enough for you to leave the house, eh? Really, I promise. ;>) Meanwhile down here in Florida it is 90 (!) degrees and the state bird (the termite) has taken wing. The only good thing about this place is that since we don't have basements we have concrete floors and get to spike everything.
Hi Jeff; I am considering either building or buying spiked amp stands for my 90 lb. DNA2s. BUT, I happened to be on the 'phone with John Dunlavy, of DAL Speakers, recently, and he is not universally impressed with spiking everything.

In fact, it's my understanding, that NONE of his speakers are spiked-- the $6K Alethas are not. He flatly stated "they don't measure better when spiked". The reason being is that most houses have wood floors with joists, crawl space, basement etc, and he says "why let your speakers or components vibrate with the floor".

His preference is to let the speakers or components "float", especially on carpet. Well, what he had to say made some serious sense, and I'm still thinking about it. My conclusion so far is as usual-- you just have to try it and see, and that it probably depends on specific conditions.

Spikes are certainly worthwhile in many situations, but not all. I know this is probably not much help, except for giving you something to think about. J. Dunlavy has had a tremendous amount of audio experience, and is one of the "heavy weights" in the audio field. It may be that either floating or isolating the amp is better than spiking (coupling) to the floor. It may also be that there is no sonic difference. Cheers. Craig.
IMHO isolation does make a difference with an amp. The key is to make you amp stand of material that is difficult to resonate. I went to home depot and purchased a concrete patio boack for 2 bucks and a can of black spray paint. The block was 24" x 24". I painted the block black and epoxied an old set of tiptoes that I cut the studs off of to the block. The total cost was maybe $25 (tiptoes included) and it will take alot to make this amp stand to vibrate.