DIY speaker isolation base for a wood floor

The granite slabs should be fairly large in dimension, maybe 18x18. 24x24 would be even better, more stable. If you can find one slab two inches thick, use that but only one slab. You want to reduce Center of Gravity height, not increase it. How heavy and tall are the speakers?

Use as many springs as you need to get the whole thing stable. Minimum 4. Might need more than 4. Did you calculate the spring rate of the springs based on total mass of speaker + Granite?

Thanks Geoff here is what I know.
102 lb load rated springs.
Spring constant 126.25 lbs per sq inch.
1.375" OD x 0.177" steel wire and 2.75 " length.
The slabs weigh 32 lbs and I  have four
The speakers are around 72 lbs.
I can get more when I go to town. I can't wait to try these. Thanks

It sounds to me like your springs are more suitable for a 400 LB speaker. The spring rate of the system is the spring rate of a spring x the number of springs.

Speakers are 42 inches tall.

People in little places , and theres billions of them. Wouldnt fit these in there places . I feel a strong spousal dispute. 

blueranger,

Quick calc says your resonant frequency is about 6Hz. That does not feel right, but perhaps geoff can check my math. I was assuming 134lbs (2x granite + speakers). That do a pretty good job at isolating most stuff over 20Hz (will be down 10x at 20Hz). Another slab of granite is not going to make much of a difference in the isolation.

Thanks audiozenology. I'm going through the myriad of springs Fastenal carries. So I should pick one that approaches its max spring capacity? They do have some in stock that has a mx bearing of 57 lbs each. Should I get those?

The argument for isolating speakers from structural vibration. isolation is a two way street. ↕️

“Max Townshend has a theory as to why they have so much effect and that’s that micro tremors in the ground are greater in amplitude than the amount of movement in a loudspeaker cone. I wrote about it here a couple of years ago but essentially there is a continuous movement in the ground produced by the earth itself and increased by factors like road traffic and even sea waves. This might seem far fetched but it’s difficult to establish why isolating a speaker should be quite as beneficial as it is. In my system the equipment is supported on a similar isolation system, so it’s not as if you are reducing the amount of vibration getting to the hardware. Townshend’s demonstrates this effect by putting tablet computers on two identical speakers, each device running an app that reveals vibration at different frequencies. One speaker is spiked the other on a Seismic Podium, all you have to do is tap the floor with your foot to see how much the spiked speaker moves, and conversely how still the isolated one stays. And if music is played through another system the spiked speaker vibrates but the isolated one doesn’t, so one reason why isolation helps is that the music itself vibrates the floor and creates a low level form of feedback.”

If the room us vibrating the walls are already enormous speakers.


When the woofer is already moving way more from say turntable rumble and your music is riding on top of that, does seismic motion matter? Seismic motion us predominantly <10 Hz and quickly drops off from their to 200hz, opposite to the Fletcher Munson curves so seismic movement would need to be more substantial to be an issue but again, the giant speaker walls are going to be orders of magnitude more an issue.

Goeffkait, can you use that expertise and review my math wrt the spring resonance for the OP?


Blueranger, what is the spring constant of the new springs (57 lb rated)?   As your platforms are not overly large, shorter springs as well would be "safer" due to less angular movement (say if you bang into them).

I know an engineer and he has restaurant clients that have him calculate how often that they need to tighten the screws on a ceiling mounted beer mug holder that you typically see in a bar.

The reason for this is primarily vibrations from vehicle traffic. If the screws aren't periodically tightened, then the beer mug rack will eventually come crashing down. Based on this example, I'd say vibration issues is a real thing.

mitchagain

I know an engineer and he has restaurant clients that have him calculate how often that they need to tighten the screws on a ceiling mounted beer mug holder that you typically see in a bar.

The reason for this is primarily vibrations from vehicle traffic. If the screws aren't periodically tightened, then the beer mug rack will eventually come crashing down

I guess this engineer doesn't believe in lockwashers.

Thanks Georgehifi! The sorbethane came in today from the eBay seller you showed me. Playing the first couple of songs of the Chicago CD I had listened to last. It sounds wonderful. Maybe placebo but I will know later tonight. I got some more springs but not wide enough and too narrow. I'm still going to try the spring method as Geoff likes some day. Right now things are sounding good!

Something is going on here. I replayed Boz Scaggs Low Down and Lido Shuffle and his voice was strident on certain passages before. It is definitely much smoother and not shrill. I will have to listen more to make sure the sorbathane is not smearing or making the bass mushy. Positive first impressions here. Spin baby spin

Ok the sorbethane is toning some things down. On The DBs  Long Train Running the 2nd ryhthm guitar is not as prevelant but sweeter. No a bad thing. I do have to listen harder to hear it. Unless the power coming into my house right now has been filtered by the audio gods, I'm hearing a positive difference. I can see why some songs people might say it takes away detail and smears But it might be system and listener dependent .But time will tell. 

Bass is better on Madonna's Erotica. I can't remember lyrics worth a dang but sounds I do remember. I don't listen to lyrics much anyway. Maybe I will try springs on down the road

Well after talking to Fastenal face to face I have decided to abandon the sprungs for now unless someone can guide me. The rep saud that's a tough spring to find. I need a short fat one for stability. Now way am I going to risk my speakers tipping over

You dont respect people's opinions. They are simply here for your entertainment. Do you want to go down the rabbit hole with me? You ruin every post here

Installed the Sorbethane pucks.   Listening to Billy Joel right now, and just got done listening to Exodus.... I'm sold.  Good post!  I bet it helps many members.  Good mod!

Thanks for chiming in Quincy. I'm sold on the pucks too