Edit: sorry I had other things on my mind, that should have read suspended floor.

What is a sonic toothbrush? Sonic teeth sounds like new hifi interface to me, and teeth need a toothbrush!

ATB from George

The Dr and I feel that a sonic screwdriver trumps a sonic toothbrush every time.

Hi George,

Yes, my teeth are cleaned using a Sonicare (google) and I used it to help me solve vibration issues with my hifi rack. Damn interesting results.

ps. bear with me, although I did this months ago, I could be some time posting this lot.

Dear Count,

Your thread has brought a smile to my face!

ATB from George

Is it anything to do with bluetooth ?

I just don't have spare time at the moment to write methods, tests and results, but for now here's self explanatory pics for you to see.

The first pic above in the thread, shows 3 3/4" square holes cut through the wood floor (8 in total, 1 for each stand foot). Then under the floorboards (with a 20" gap between concrete and floorboards) I built 8 individual pillars using foundation blocks and concrete bricks. This was ridiculously difficult in a confined space, but I didn't want to destroy my floor or make unnecessary mess in my room above.

Then to build the height up through the boards, I cemented 3 1/4" hard stone tiles. Obviously avoiding touching the wood.

Next cement a 4" granite tile to the stone. Leaving a gap between it and the wood.

Make sure it's level.

Also make sure all 8 tiles are level to each other.... a pain.

Finish off with a low density foam between the floor and tiles to stop draughts coming up from below.

Now my system is totally isolated from the direct effects of the suspended floor.

That is an incredibly classy setup.

Really neat!

I have often thought of something like this.

How does it sound?

Richard

A lot of thought and hard work there count.
Well done.
How does it sound?
Stu

Great work. My wife thought I was obsessive when she saw me glueing and screwing aluminium sheet under my speakers to stop the spikes sinking in. I'd love to try this myself, but as my room is upstairs I'd stuggle to convince her that 8 brick pillars through the lounge below is domestically acceptable...!

Very nice solution. I just hope your wife is happy with the location of the system and does not decide to redecorate!

Superb job. Nice racks too

James

Wow fantastic job.

a very neat solution to a perrenial problem.

Trouble is in my appartment the gap between floorboards and ground is several feet!

David

Thanks for the compliments chaps. Sorry for not replying sooner, but I'm in and then back out all the time at the moment.

How did it sound? It took a lot of work (and sourcing of materials) to do this small project and the more work one does, the higher the expectation of the results. I had big expectations and I thought it would solve most vibration issues.... and I suppose it does. The comparison between floor boards and concrete under the rack here is very interesting, as nothing else has changed and I know the exact sound from my hifi. The biggest difference is in the bass area. Better definition in the deepest parts and I hear things I've not heard before. Very deep parts of the bass, which weren't there before, just tickle you. Drums have much more impact, are clearer and have sharper attack on the leading edge. Midrange opened up slightly and the treble a little sweeter, but the bass is the main improvement.

You have to take into account the fact that my two racks are already semi isolated from the effects of my speakers as they are 6m to the left in an ajoining room (see plan). I would have thought that if the racks were in the same room, and directly in line of fire, the results would have been greater.

After the project was completed, one of the tweaks I learnt, was by banging the floorboards around/under the racks. Although the boards have no contact with the rack, the noise produced still excited the levels, especially the bottom one. Obviously sound waves generated by boards will cause the whole rack to "sing", but I found that there's a trampoline interaction between boards and bottom level. I placed 2" thick acoustic foam on the boards directly under the racks to cut out the interaction and hey presto, bottom level vibration slightly reduced. Slightly reduced....ok so it's not perfect, but better than nothing. Anyone can do this. One can't put foam on unused levels, as it will deaden the rack's ring.