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Early B.
06-12-2005, 08:30 AM
I have a pair of the Parts Express speaker stands for my Norh 5.1's. They weigh 25 lbs. each and are sand fillable, but I never bothered to fill them with sand. Is it worth doing? Has anyone done this and noticed a difference in SQ?

tryrrthg
06-12-2005, 10:32 AM
Go for it. The sand will cost like 3 bucks. Worth every penny! ;)

it should tighten up your bass response.

Polkapops
06-12-2005, 10:48 AM
No kidding?! I just figured the sand would make them more stable is all - kinda like a patio umbrella. This hobby sure has a lot of cool (if not quirky) tricks to it's trade....
Living near the great lakes, the sand is free up here - I'd be happy to get you some but it'd probably cost more to ship it than it would to buy it! :D

marcpam
06-12-2005, 11:08 AM
nice amp you got there

F1nut
06-12-2005, 01:09 PM
Heavier than sand is lead shot. I just mass loaded a pair of CRS stands, they took 22lbs. of shot each. If you've seen the stands, there isn't that much to them and sand wouldn't have added anywhere close to that weight. For speakers stands, the more they weigh the better.

madmax
06-12-2005, 01:12 PM
I read a good article about stands one time where the listener (with really good electronics and speakers, I forget what) tried 15 or so different stands and got about 10 different results. He was of the opinion that the different stands made quite a difference to the sound. I've never tried it myself so I have no real opinion. I would say go with it and see. Apparently there are differences in sound when you go with lead shot vs ball bearings vs sand vs pea gravel. :confused:
madmax


Edit: Oh yea, just remembered, the difference between the differences in material used was that something like ball bearings allowed the vibrations to turn more to heat because the surfaces could rub against each other a lot more than sand or pea gravel. I believe he said concrete or other solid weight does little as far as sound quality. Like I say though, never tried it. I would like to fill the bottoms of my SDA's up with ball bearings one day just to see what it does.

Larry Chanin
06-12-2005, 03:57 PM
Originally posted by madmax
I read a good article about stands one time where the listener (with really good electronics and speakers, I forget what) tried 15 or so different stands and got about 10 different results. He was of the opinion that the different stands made quite a difference to the sound. I've never tried it myself so I have no real opinion. I would say go with it and see. Apparently there are differences in sound when you go with lead shot vs ball bearings vs sand vs pea gravel. :confused:
madmax


Edit: Oh yea, just remembered, the difference between the differences in material used was that something like ball bearings allowed the vibrations to turn more to heat because the surfaces could rub against each other a lot more than sand or pea gravel. I believe he said concrete or other solid weight does little as far as sound quality. Like I say though, never tried it. I would like to fill the bottoms of my SDA's up with ball bearings one day just to see what it does.

Hi,

Since Early has spikes on his stands he is coupling them to the floor. The big question is, "Which would sound better, speaker stands coupled to the floor, or decoupled?"

I believe the answer depends on the construction of his floor. If his floor is resilient, i.e. wood floors, increased coupling could produce sympathetic vibrations in the floor. The floor vibrations could interfere with the direct bass coming through the air and muddy the presentation.

If the floors are massive and rigid, i.e. concrete slab, they are much less likely to vibrate when coupled to the speaker stands. However, as you may have alluded to, concrete still transmitts bass quite well in comparison to other materials.

For this reason, regardless of the floor construction, many professional home theater designers construct a stage in the front of the room and place the subwoofer(s) and front speakers on it. The stage is rigidly constructed to resist vibrations, and filled with sand to absorb transmitted bass. It is the mass of the sand and the friction between the sand particles that mitigates the transmission of the bass.


http://mysite.verizon.net/res8ycu4/sitebuildercontent/sitebuilderpictures/sda-1cl.jpg
I've placed massive, solid concrete block stands under my SDA's on my home theater stage, and filled the stage with 1,000 pounds of sand.

I only use these example to show how mass and sand can decouple the speakers from the floor. Obviously, I am not suggesting that Early build a stage. However, depending on the construction of his floor it might be worthwhile to experiment not only with coupling spikes, but with isolation rubber feet. I think in either case adding mass shouldn't hurt.

With regard to the use of lead shot or ball bearings versus sand, although they are more massive, I would think that since they are larger they would have less friction than sand. (For example, larger diameter tires have less drag, rolling resistance, than small tires.) An other minor concern I would have regarding metal balls would be that they might have more of a tendancy to buzz when vibrated against one an other.

Larry

F1nut
06-12-2005, 04:44 PM
This is all very interesting. As I understand it, the use of spikes on stands is to decouple them from the floor there by preventing the bass from transfering vibrations and become muddy. This is the theory behind all isolation cone devices. The same applies to mass loading stands.

Early B.
06-12-2005, 05:08 PM
OK, based on the responses here, I ran to Home Depot, bought some sand and filled my speaker stands with 'em. Probably added another 10-12 lbs. to each stand. Popped in a CD and listened. Not sure if it really made a difference, though. Do I need to wait for the sand to break in?:p

Polkapops
06-12-2005, 05:42 PM
ROFLMAO!!!!!!!!!!!!!
good one, Early B :D :) ;) :p

F1nut
06-12-2005, 05:47 PM
(For example, larger diameter tires have less drag, rolling resistance, than small tires.) An other minor concern I would have regarding metal balls would be that they might have more of a tendancy to buzz when vibrated against one an other.



Two things here.

First, the rolling resistance of a tire is based, in part, on the contact patch. If a large diameter and small diameter tire have the same contact patch the rolling resisitance should be the same. However, the larger the diameter tire will cause the rpm's to drop compared to a smaller diameter tire (unless the final drive ratio is changed to compensate) resulting in the need for more power to be applied and in turn using more gasoline. Jstas, feel free to chime in here.

Second, lead shot does not vibrate, dead mass.


I think sand is fine to use, but if one needs more weight per volume, then lead shot would be a better choice.

tryrrthg
06-12-2005, 06:53 PM
Originally posted by F1nut
I think sand is fine to use, but if one needs more weight per volume, then lead shot would be a better choice.
I've always read that the best way to do it is filling your stand with shot AND sand. The sand will fill all the voids between the shot.

I've never gone looking for lead shot. How expensive is it?

RuSsMaN
06-12-2005, 07:11 PM
Sand, Shot, all good choices.

If you can stand the dust during the fill, scoopable (fine) kitty litter is the best of both worlds. Heaver than sand, cheaper than shot.

Cheers,
Russ

madmax
06-12-2005, 07:17 PM
The thing I keep going back to in my mind is the idea that the way vibration is disipated is through heat created by micro movement of the material. The vibrations must go somewhere, they can't disappear. Given that I have to wonder if putting sand and lead shot together wouldn't just become a hard mass, therefore transmitting the vibration rather than disipating it.
madmax

RuSsMaN
06-12-2005, 08:06 PM
That's a good point Chuck, however more mass = less vibes, or you could say more mass requires much more energy to trasmit the same vibes as less mass.

In theory the large vibes will be translated (broken down) into very tiny vibrations between the small spaces around the sand/shot. Granted they are VERY tiny, but they are also occuring on an exponential scale.

Cheers,
Russ

F1nut
06-12-2005, 08:17 PM
Originally posted by tryrrthg
I've always read that the best way to do it is filling your stand with shot AND sand. The sand will fill all the voids between the shot.

I've never gone looking for lead shot. How expensive is it?

Not a bad idea.

$19.99 per 25lb. bag of #5 shot at Bass Pro.

Early B.
06-12-2005, 10:11 PM
I just realized the practical problem with spikes on speakers or speaker stands -- the floor has to be level. I just gave one of my 35+ lb. sand filled speaker stands a slight nudge with my fingertip and it melted like butter. OK, maybe I'm exaggerating, but even if I added more weight, the problem would remain. I have a carpeted wooden floor that gives up after a little pressure just like Mike Tyson.

Damn, now I need to buy marble tiles for the stands to stand on. Gotta get something that can withstand the WAF (pun intended).

To make it work, I'll need two 13" x 11" tiles. Any ideas?
What about painted 3/4" MDF with spikes on 'em?

michael_w
06-12-2005, 10:31 PM
Could use some pretty concrete garden tiles that you could pick up at home depot for less than 10 bucks each...

tryrrthg
06-13-2005, 09:12 AM
Originally posted by F1nut
$19.99 per 25lb. bag of #5 shot at Bass Pro.
Thanks! There are no Bass Pro's in my neck of the woods but I've got a few other places that might work out.

How large is #5 shot? Are we talking the size of a BB from a BB gun? Smaller? Larger? Just curious, thanks!

Willow
06-13-2005, 09:26 AM
Originally posted by Early B.
OK, based on the responses here, I ran to Home Depot, bought some sand and filled my speaker stands with 'em. Probably added another 10-12 lbs. to each stand. Popped in a CD and listened. Not sure if it really made a difference, though. Do I need to wait for the sand to break in?:p


Actually there is not break in but, the sand does take some time to settle . When i filled mine, they where full when I sold a set of my stands I could have added a couple more inches as the sand had time to settle

F1nut
06-13-2005, 01:16 PM
#5 shot is slightly smaller than a standard BB. It does come in larger sizes, but that was the biggest Bass Pro had in the store.

madmax
06-13-2005, 02:16 PM
Originally posted by RuSsMaN
more mass requires much more energy to trasmit the same vibes as less mass.
Cheers,
Russ

More mass just lowers the resonant frequency. At a lower frequency it still takes the same amount of energy to vibrate the same amount. At least that is my understanding. Of course at higher frequencies than resonance it would indeed take more energy to cause vibration.

madmax

ND13
06-13-2005, 02:27 PM
Originally posted by RuSsMaN
Sand, Shot, all good choices.

If you can stand the dust during the fill, scoopable (fine) kitty litter is the best of both worlds. Heaver than sand, cheaper than shot.

Cheers,
Russ

Petsmart is having a sale on TidyCat brand scoopable litter this week.:D :D :D

Willow
06-13-2005, 02:38 PM
Originally posted by ND13
Petsmart is having a sale on TidyCat brand scoopable litter this week.:D :D :D


COnstruction sand is still cheaper. 40lb bag for 3.99$ thats what I paid

Toxis
06-13-2005, 02:54 PM
I can't speak for sand, but when I added lead shot to my stands, WHOA! Definitely improved the midbass response. Gave the speakers a "More stuck to the floor" sound. But I paid $20 for a 25lb bag.

Early B.
06-15-2005, 09:41 AM
Here's what I ended up doing -- I went to Home Depot and bought two 13" x 13" ceramic tiles for $2.14 ea. and placed them underneath my stands. The stands still wobble slightly when a little pressure is applied to them, but it looks kinda cool because all of the spikes are fully visible. It also raised the speakers about an inch higher. Don't know if it made a sonic difference, though. However, I noticed the subtle difference the 1 inch in speaker height made.

tryrrthg
06-15-2005, 09:54 AM
Originally posted by Early B.
The stands still wobble slightly when a little pressure is applied to them, but it looks kinda cool because all of the spikes are fully visible.
Can't you adjust the spikes so they level out the stands/speakers? I have to adjust my spikes so that the speakers and stands sit level. They don't budge after I do that.

egp823
06-16-2005, 10:28 PM
F1nut,

How did you fill up your CRS stands? I have the original stands but could not see any opening for loading. I see some plastic caps though but these might have stuck with age as I can't pry them loose. If these are the opening will try to force them loose. Thanks for any advise.

F1nut
06-16-2005, 11:28 PM
LOL.....removing the caps was the hardest part. I used a single edge razor blade positioned between the plastic cap and the metal frame, tap the razor gently around all 4 edges of the plastic cap/frame with a small hammer to help break the grip. It won't do much, but get things started. I then used a 1" chisel, tapping it gently while at a slight angle away from the frame. You have to do a little on one edge, then a little on another edge going around all 4 edges until it pops out. Be careful not to damage the plastic by hitting the plastic too hard, the chisel will cut though it easily. At least mine will, I keep them razor sharp. You have to remove all 4 caps in order to fill all of the frame. The bottom is one section, the two posts are each a section and the top is one section. There is a small hole on the back edge of the bottom section. I covered it with thin, small round felt pad to prevent the shot from falling out and back off the screws for the spikes/feet, but do not remove them. Fill the bottom section first, then put the 2 caps back on. Just inside the top section is a small opening to the top of the posts, pour the shot in there. Next, fill the top section, a little tape over the opening for the posts will keep the shot from falling out. When you're done filling the top put the caps back on, screw the spikes/feet back in place and you're done. I used about 22lbs. of shot per stand and would shake/tap the frame to help settle things as I went.

egp823
06-16-2005, 11:59 PM
tks will check it out tonight.