Currently have 2 X FF BK Xlls400 and wish to optimise isolation from suspended wooden floor. They are placed on 40mm thick multi staves oak platforms which sit/float on very thick carpet and sound absorbing thick under lay.
The subs have feet with 8mm spikes these are placed into spike shoes directly on the platforms.
I've looked into the concepts of both coupling and isolation.
I believe it best not to couple the subs to my floor because it will channel some of the bass into this structure and essentially act as a big sounding board.
So the only isolating part is my carpet and under lay.
I would invite you guys ideas and thoughts on how best to achieve improvements.
Here are a few of my thoughts;
Spend £120 on svs soundpath subwoofer rubber feet on the subs straight on to the oak blocks.
Decouple further the oak blocks by fitting chunky rubber castor wheels ( this will also allow me to move the subs position easier)
I also had some thoughts on coupling the subs to some same size concrete/ granite blocks using existing sub spikes and shoes to this, then leaving the oak blocks on place on the carpet placing say 4 to 5 50mm sorbothane domes on each, then place both the slabs and sub on top. My objective here is to deliberately pull/ couple/ channel the bass energy from the subs into the mass of the slabs and then decouple/ isolate this mass from the suspended wooden floor using the combo of underlay,carpet,oak block,large sorbothane domes/blocks.
I'm new by the way 😃👍
Cheers Matt
The subs have feet with 8mm spikes these are placed into spike shoes directly on the platforms.
I've looked into the concepts of both coupling and isolation.
I believe it best not to couple the subs to my floor because it will channel some of the bass into this structure and essentially act as a big sounding board.
So the only isolating part is my carpet and under lay.
I would invite you guys ideas and thoughts on how best to achieve improvements.
Here are a few of my thoughts;
Spend £120 on svs soundpath subwoofer rubber feet on the subs straight on to the oak blocks.
Decouple further the oak blocks by fitting chunky rubber castor wheels ( this will also allow me to move the subs position easier)
I also had some thoughts on coupling the subs to some same size concrete/ granite blocks using existing sub spikes and shoes to this, then leaving the oak blocks on place on the carpet placing say 4 to 5 50mm sorbothane domes on each, then place both the slabs and sub on top. My objective here is to deliberately pull/ couple/ channel the bass energy from the subs into the mass of the slabs and then decouple/ isolate this mass from the suspended wooden floor using the combo of underlay,carpet,oak block,large sorbothane domes/blocks.
I'm new by the way 😃👍
Cheers Matt
Coil springs. Possibly around the legs ?
I have used a combination of coil springs in foam that works quite well.
I have used a combination of coil springs in foam that works quite well.
The floor of Galaxy Studios, in Belgium, is held up on springs - They claimed it gave them room isolation of 100db down to 3hz or something crazy.
To the OP, how about making a, multi layer, sandwich using Green Glue: Green Glue Noiseproofing Compound and something like this: Mottez Shock-Absorbing Floor Mat Grey / Blue 620 x 620mm | Matting | Screwfix.com
Because your FF you could just target the feet: Raise It Isolation Feet for Speaker Vibration/Ventilation and Cooling for Consoles PS4, PS5, Xbox, PC, DVD Player, Internet Router/Universal Fit/Non-Slip / 12 Pack: Amazon.co.uk: Electronics & Photo
Thanks CJ..food for thought...
Just to say I don't think I'm getting a lot of bass energy going into the floor. The subs are very well supported on their spikes to shoes on the 40mm solid oak. It not clear from Amazon how many of the rubber feet you get?
Question: coupled and spike supported subs into mass with that mass isolated as best as poss from floor VS subs supported by directly contacting isolation ie rubber/sorbothane feet?
Whatever I decide to try it won't involve car suspension or tree swings����
Just to say I don't think I'm getting a lot of bass energy going into the floor. The subs are very well supported on their spikes to shoes on the 40mm solid oak. It not clear from Amazon how many of the rubber feet you get?
Question: coupled and spike supported subs into mass with that mass isolated as best as poss from floor VS subs supported by directly contacting isolation ie rubber/sorbothane feet?
Whatever I decide to try it won't involve car suspension or tree swings����
I had a need to isolate subwoofers for a small nightclub. The basic principle of isolation is mass on compliance. Hence to increase the isolation the objective is more of both. In this case I suspended a precast concrete paver on industrial vibration isolation mounts, chosen to give a natural resonance with the subs on the slab of ~5Hz. This forms a mass / spring / damper system which acts like a low pass filter, preventing the coupling of frequencies above resonance with a first order slope of 6dB per octave, or about 12dB at 20Hz, 18dB at 40Hz, etc.
Attachments
Since you have two, is it possible for you to try bolting them back to back and see how much force cancellation you can achieve?
Perhaps this post (and the thread) would help explain the idea.https://www.diyaudio.com/forums/multi-way/287842-push-push-bass-design-7.html#post6761012
It's basically making the drivers, or cabinets act against one another and can be very effective at getting rid of vibration and motion
It's basically making the drivers, or cabinets act against one another and can be very effective at getting rid of vibration and motion
If you're not a studio engineer your goal is nonsensical. Speakers are in the reproduction business. You're in the crowd listening your favourite band. Half the sound from the bass-player's 4 x 15s are reaching you through the floor on account of his speakers being on the floor.
Step away from the spreadsheet.
Step away from the spreadsheet.
In the example I posted above decoupling the subwoofers from the structure of the building made an extraordinary improvement to the perceived quality of bass - even live recordings of bands thumping away sounded extraordinary throughout the entire space. Speakers are in the reproduction business, but the room structure is not and benefits from being decoupled, rather than being allowed to be an uncontrolled auxiliary coupled resonance system.
Have look at this site Technical Info - AV Industrial
They have conical pads, for a couple of quid each, along with industrial mounts as per johnmaths comments.
(FYI, the AV stands for ‘anti vibration’ not ‘audio visual’)
They have conical pads, for a couple of quid each, along with industrial mounts as per johnmaths comments.
(FYI, the AV stands for ‘anti vibration’ not ‘audio visual’)
Basic issue is relation of cone to your ears. Once the enclosure is moving or floating, that relationship is crap. Ideal is a solidly steady box - I've used cinderblock weights since the floor is the steadiest reference.
Doubly deadly to good sound if the enclosure is responsive to the freq the cone is acting on. Duh.
Nothing wrong with having the whole floor vibrate as any dipole or panel owner can tell you. Only issue is possibility of tone colouration from floor resonances - which for a sub at home, is just a tiny issue compared to other acoustic horrors.
Doubly deadly to good sound if the enclosure is responsive to the freq the cone is acting on. Duh.
Nothing wrong with having the whole floor vibrate as any dipole or panel owner can tell you. Only issue is possibility of tone colouration from floor resonances - which for a sub at home, is just a tiny issue compared to other acoustic horrors.
The effect of an enclosure moving in reaction to the cone movement is a slight reduction in SPL.
There are no major issues with excessive bass vibration. They sound good. I would just like to experiment with ways to improve the acoustic bass energy by decreasing the amount of vibrational bass that will be exciting my suspended wooden floor.
Im going to try out some foam matting pads under the the oak worktop that and some big rubber/silicon/sorbothane footers instead of the spikes. I'll report my thoughts on that when tried.
Im going to try out some foam matting pads under the the oak worktop that and some big rubber/silicon/sorbothane footers instead of the spikes. I'll report my thoughts on that when tried.
Linkwitz doesn't mention any other issues here except resonances Issues in speaker design - 2
The other distortions would exist to a large degree regardless
The other distortions would exist to a large degree regardless
Thinking of elevating the subs a little to get them off the floor. Thinking 8-12inches on either hairpin legs, metal furniture legs or large castors. I will also try moving them out from the corners a little, not much though due to cable length.