Stands, slabs and sorbothane - coupling and decoupling on carpeted wooden floors

nobo

Well-known member
Jul 25, 2007
5
3
18,525
Visit site
Hi,

I have some PMC TB2+ and 1m high Atacama sand filled stands, together with a PMC XB1 sub (a large beast at 27cm deep, 78cm long and about 28kg). I also have 2 sets of Auralex MoPads.

I’m wondering what the best arrangement is for setting these up in terms of coupling/decouping in a loft room (converted loft in a Victorian terraced house) with a wooden floor which has been carpeted. More specifically:

i) How should the TB2+s be attached to the stands? Just placed on them, or on top of blu tack balls / sorbothane hemispheres / Mopads or something else?

ii) How should the stands be attached to the floor? The spikes are removeable. I suspect I’ll get floor resonance issues spiking through the carpet or, because the carpet (53oz) and underlay (10mm Duralay System 10 underlay) are fairly thick, the spikes may not even reach the wooden floorboards. Might it be worth getting some slabs (pavings slabs/granite tiles, etc) to sit under the stands? Should these rest directly on the carpet, or on MoPads/sorbothane?

iii) How should the sub sit on the floor? It doesn’t have spikes/there’s no option to install them. I could use MoPads to decouple it. Or sit it on granite. Or sub/MoPad/granite/sorbothane … etc….

Minimising vibration transition to the floor would be desirable to help keep family and neighbours happy, so I’m thinking additional mass and decoupling.

Suggestions welcome!

Many thanks in advance.
 

nobo

Well-known member
Jul 25, 2007
5
3
18,525
Visit site
Hi Robin,

Yes, I'm equally confused as to why there isn't clearer, um, "science" on this - especially when it can be objectively tested by recording the sound in the room and comparing.

Some people seem to suggest slate and/or sandstone is preferable to granite, but general consensus is that mass is what's required. Various conflicting guidance on decoupling, etc, and what the best materials are for that (though it seems arguments for sorbothane are strong).

Could you point me to the granite slabs you got from BnQ? After some myself (depending on the answers to this thread!), but can't find the ones you bought online (I was wondering about piling up granite tiles).

I'm thinking speakers - sorbothane hemispheres - stands - spikes - coins to hold spikes - granite slab - [possibly sorbothane hemispheres/sheet or mopads] - carpet. Thought there's not much science behind that, save for decoupling/mass/compression at a very basic level. The carpet/underlay probably provides a fair bit of decoupling, though not at a calculated frequency...
 

RobinKidderminster

New member
May 27, 2009
582
0
0
Visit site
Picked my slabs up at local b&q. 40x40x2cm. Blue or purple something reduced from £3.50ish I think.

My thought, trying it with my sub first, maybe something like....

Push 3 nails thru ply to make spikes. blutac between ply and slab. Then blutac to next slab. Then blutack under the subs plastic coned feet.

Maybe over the top. Maybe useless. Worth a try for £5 and half an hours work. Will let u know if my bass is magically transformed. (or not). :)
 

nobo

Well-known member
Jul 25, 2007
5
3
18,525
Visit site
Keep me posted! Photos welcome :)

I think I'm going to try:

Speaker

Blu tack

Stand

Spikes

(Coins)

Stone slab (granite, sandstone or other material)

Carpet

I was thinking about putting coins under the spikes to protect the granite (if that's what I use).

Depending on the stone material, it may be worth seeing if I can do something to protect the carpet. I've heard of certain slabs (e.g. sandstone, paving material) retaining moisture and leeching it into the carpet, ruining it. So raising it off the floor - perhaps with sorbothane hemispheres - or something else (???) seems wise, if you're not using something like granite/marble.

For the sub:

Sub speaker (it doesn't have spikes)

Blu tack (or sorbothane)

Stone slab (as above - if granite, bonded or sorbothane layer?)

Mo Pads (which I have spare)
 

JamesMellor

New member
Jul 19, 2013
40
0
0
Visit site
Hi Robin ,

True , and we never get the weather for sitting out anyway , but instead of nails maybe these :

http://www.ebay.co.uk/itm/4-Solid-Brass-M6-Speaker-Spikes-Feet-Housing-Height-Adjustable-For-Rack-Stands-/231173113310?_trksid=p2054897.l4276

I assume you drill a push fit hole for the bottom part then tap that home and adjust using the thread and lock nut , just for the look of the thing although at 6 quid it doubles the cost

James
 

RobinKidderminster

New member
May 27, 2009
582
0
0
Visit site
Nice one James. If my nails benefit I'll go with those brass babies. :) I have made the base on 3 rather than 4 nails since they will self level in the absence of adjustment. I doubt I will hear any difference but willing to try. A neat 'skirt' will be easy if they remain a keeper. And then onto my front floorstanders.

Interesting that the centre is vital in hc but difficult to mod. Mine (pics) sits in a unit. Blutac is about the only mod possible.Any ideas?
 

JamesMellor

New member
Jul 19, 2013
40
0
0
Visit site
LOL , I've seen your pic's before didn't think you'd stick with nails , as for the centre aren't they kinda designed to live in racks ?

Whats that rack your amp is on btw, podium ? they are ddg imo , I want one of those

James
 

RobinKidderminster

New member
May 27, 2009
582
0
0
Visit site
JamesMellor said:
LOL , I've seen your pic's before didn't think you'd stick with nails , as for the centre aren't they kinda designed to live in racks ?

Whats that rack your amp is on btw, podium ? they are ddg imo , I want one of those

James

I'm blushing James. Or is that blood from hitting thumb instead of nail? My new rack is Blox which I chose to match the other furniture. The metal rack cost me £320 but I cant sell it on Gumtree for £100..Muat find it a new home somehow but so heavy.

I would think a centre speaker on dedicated stand would be better but not really lounge friendly. Mmmmmm. These slans wont fit too well..Need to mobe the side tables ... Mmmm. :wall:
 

JamesMellor

New member
Jul 19, 2013
40
0
0
Visit site
I didnt notice a metal rack , but I guess they're worse than speaker stand for shipping costs , plus the glass shevles to wrap , Good Luck with the patio / sub stand

James
 

RobinKidderminster

New member
May 27, 2009
582
0
0
Visit site
Somewhat off topic but looking at Blok Stax 300 its now £600. I paid £300. Maybe they have radically changed the structure but looks the same. Anyway - back to me slabbin'. .........
 

RobinKidderminster

New member
May 27, 2009
582
0
0
Visit site
Getting back to op (just before creating a new patio) I dont find a great benefit in my sub/slab experiment. Maybe a little tighter? Maybe placaebo. Maybe my morning ears? I dont think I will keep them since the 'look' does not warrant any perceived improvement. Had there been an improvement I would have sourced a thicker slab & had it cut and polished as well as the aforementioned spikes. I would still be interested in others evaluations and I may leave my slab for now.
 

RobinKidderminster

New member
May 27, 2009
582
0
0
Visit site
Or does it sound better?? :wall:

I now have suspended floorboard - spike (nails) thru carpet held in chipboard. blutak (on (large) nail heads) - slab - blutak - slab - spike - subwoofer. Yet to listen. If it improves I will buy proper spikes and get the slabs cut to size. Fronts are already (too) tall so I dont wish to raise them by 50mm so kinda hope my sub experiment fails.

Makes me wonder if subs are best on the floor or if raising them by cms has a good/bad effect?
 

drummerman

New member
Jan 18, 2008
540
5
0
Visit site
This is what I do; Fill the stands, get some sorbothane pucks for the top plate, speaker on those and a nice, heavy doorstop on top of the speaker. This should give audible improvements. I also re/hard wire all my speakers internally and added damping sheets in place of the filler that comes supplied. - With my Missions I further filled the front plate with medium density foam. The tweeter is now almost completely de-coupled from the rest of the speaker.

Whilst all this may go a little far for some, the sorbothane pads are very good 'isolators' (they actually turn vibrations into heat) and on their own should make an improvement.

Sorbothane (and pro-foam panels) are very good materials to rest speakers and other electronics on. The only place I wouldn't use it is turntables.

regards
 

RobinKidderminster

New member
May 27, 2009
582
0
0
Visit site
Hi (again) DM. Some of yr suggestions seem worthy tho with my floorstanders I would be reluctant to break open their boxes. Rear stands might get the sand treatment. I am listening right now and frightened that my slabbing may have tightened things up. Taking things back to op - still wonder why no definitive method to 'mount' speakers. Best do some more sucking and seeing
 
U

unknown

Guest
drummerman said:
This is what I do; Fill the stands, get some sorbothane pucks for the top plate, speaker on those and a nice, heavy doorstop on top of the speaker. This should give audible improvements. I also re/hard wire all my speakers internally and added damping sheets in place of the filler that comes supplied. - With my Missions I further filled the front plate with medium density foam. The tweeter is now almost completely de-coupled from the rest of the speaker.

Whilst all this may go a little far for some, the sorbothane pads are very good 'isolators' (they actually turn vibrations into heat) and on their own should make an improvement.

Sorbothane (and pro-foam panels) are very good materials to rest speakers and other electronics on. The only place I wouldn't use it is turntables.

regards

by filling speaker stands (to increase mass), using sorbothane between stand and speaker and using a weight on top of speaker, does this not trap vibrations inside the speaker cabinet (energy storage) causing a fuzzy smeared sound ?
 

drummerman

New member
Jan 18, 2008
540
5
0
Visit site
mikefarrow said:
drummerman said:
This is what I do; Fill the stands, get some sorbothane pucks for the top plate, speaker on those and a nice, heavy doorstop on top of the speaker. This should give audible improvements. I also re/hard wire all my speakers internally and added damping sheets in place of the filler that comes supplied. - With my Missions I further filled the front plate with medium density foam. The tweeter is now almost completely de-coupled from the rest of the speaker.

Whilst all this may go a little far for some, the sorbothane pads are very good 'isolators' (they actually turn vibrations into heat) and on their own should make an improvement.

Sorbothane (and pro-foam panels) are very good materials to rest speakers and other electronics on. The only place I wouldn't use it is turntables.

regards

by filling speaker stands (to increase mass), using sorbothane between stand and speaker and using a weight on top of speaker, does this not trap vibrations inside the speaker cabinet (energy storage) causing a fuzzy smeared sound ?

A hollow speaker stand rings like a bell. If you have wooden floor boards the whole thing can become one whole vibrating mass. On a turntable metal platter one way to stop the ringing (in addition to using a mat and the record) is to add peripheral rubber rings. That is inpractical with speaker stands.

Short of a Townshend seismic sink for speakers/stands or 'no cabinet' I would hazard a guess that a combination of different materials and weights is the best way to get the speaker cabinet (and supports) out of the equation, at least in my room. The top weight helps grounding the cabinet on the sorbothane.

There is a different school of thought ie. Harbeth, Spendor, Totem which use minimal damping and on occasions light weight open frame stands but in my system/s everything has substantially improved.

regards
 

RobinKidderminster

New member
May 27, 2009
582
0
0
Visit site
Listening to some music - seems my slab experiment has had more effect than I'd thought. The bass is undoubtably enhanced. Having to turn it down substantially from its normal setting. Maybe the 50mm height increase? Cant find info wrt sub height. Guess I need to get the spikes and the services of a stone cutter. Less noticable with cinema (predictably I guess) but with 2ch music I am surprised. Certainly worth £7-£10 experimentation.
 

matt49

Well-known member
Apr 7, 2013
58
14
18,545
Visit site
RobinKidderminster said:
Or does it sound better?? :wall:

I now have suspended floorboard - spike (nails) thru carpet held in chipboard. blutak (on (large) nail heads) - slab - blutak - slab - spike - subwoofer. Yet to listen. If it improves I will buy proper spikes and get the slabs cut to size. Fronts are already (too) tall so I dont wish to raise them by 50mm so kinda hope my sub experiment fails.

Makes me wonder if subs are best on the floor or if raising them by cms has a good/bad effect?

So just to be clear: does the treatment above apply just to the sub?

Presumably the effect is to (almost) completely decouple the sub from the floor.

I currently have my subs on their integrated rubber feet on top of 20mm thick marble, which sits on the carpet. Very much a temporary fix, the speakers being only a couple of weeks old. The subs also have spikes, but I want to decouple them from the floor. So I'm interested in your approach.

Matt
 

TRENDING THREADS