Stone blocks under speakers.

[whoaru99]

I'm not Pete, but I've had mine in two different rooms both with and without the cinder block stands, in exactly the same location and with the same upstream equipment.

I'll echo what he said... "They do make a difference! Bass was much tighter and cleaner. The mids and highs seemed clearer too, but there is the fact that they were raised a bit, which with my short speakers probably made a difference too."

I agree 100 percent. Whatever stand I wind up building, I want it to be HEAVY

Were the speakers on carpet prior to the blocks?

Understand that this may seem like I'm doubting the effects, but I'm very analytical by nature and mostly my questions are trying to understand why the block (or whatever) might have an effect.

 

[piece-it pete]

Pete, was that comparison with the speakers in two different places?

In other words, the speakers were tested on the blocks in a different physical location than where they were without being on the blocks?

No, they were set on the blocks right where I usually place them, for an apples to apples comparison. Normally they are on a carpeted concrete floor, using the factory spikes.

Is one to infer that the tightening of the bass and clearing of the mids and highs is due to the composition of the sandstone blocks? As a lowly, broke grad student I have my speakers up from the floor on rather low-brow milk crates and could describe benefits similar to yours.
Have you had your speakers off the floor with other objects and now, with the sandstone blocks, find these benefits in sound further refined? I ask this because it would seem that getting your hands on sandstone blocks could be far more cost efficient than some of the items advertised and sold for BIG money in audiophile mags and the like. Thanks.

That's a great question and I should have thought of it. As a matter of fact I feel a bit of d'oh! as I knew that height mattered.

Now I need something 2" thick that isn't dense to try, a block of wood perhaps? Then, the new product line: audiophile sandstone. Bose approved. It's better!!

dmusgrave, if you have a builder's supply house near you give them a call - there is a large one near me that has auctions every couple of months for unclaimed or drops of granite, marble, etc, I've never gone but have been planning on it for a couple of years . I bet they cut and shape too.

And your book tweak, I second that, except instead of a book on a cd player I put the records I've already played on my dustcover, same thing, methinks. Agreed, it works!

Pete

 

[archie2]

I'm no engineer, but, I'm thinking I'll make the plates fairly thick, possibly layers of MDF. I could then route out recesses in the top of the bottom plate and the bottom of the top plate to recess the PVC about 1/2" into the plates and seal them with silicone to avoid sand leakage. I also plan to run a threaded rod through each PVC pipe and attatch a washer and nut on both ends (of course recessed into the plates.)

I figure between those things, and filling with sand, I can get them stable enough. I may wind up going with 3 or 4 PVC risers per stand depending on stability.

I plan to veneer them in the same veneer as I'm going to use when I re-veneer my HPM-900's, and finish them off with some floor spikes, so the whole thing might come out looking and working really nicely. A customer of mine offered to chrome the PVC risers for me at no charge... I think that will look pretty sweet :thmbsp:

Or... it may crash to the ground :lmao: It's going to have to be pretty heavy duty... the speakers ain't no bookshelf jobs!

Just something you can look at if you wish, but go to Home Depot and look at the solid yellow pine stair treads. They sell for about $10.00 each and are 4' x 12" x 1". If you cut four 8" pieces you will have four 8" x 12" bases. Then cut four 4" pieces and you will have four 4" risers, two per speaker stand. Home depot will do the cuts for you at 25 cents per cut. You will end up with 2 speaker stands having 8" x 12" bases with two 4" x 12" risers each. The yellow pine is finished wood and stains very nicely. Cheap way to go for some nice looking heavy speaker stands. Now you can do the same thing in solid oak but it'll cost you about $23.00 for the wood.

 

[cfranz]

Just do a search using 'diy speaker stands' and you'll get plenty of ideas. Some of them even worth the trouble.

 

[dmusgrave]

You might want to consider capping your PVC speaker stands with a PVC floor flange as can be seen in this picture, though there are various types similar to this.

http://www.plumbingsupply.com/images/toiletflange-pvc-stainless-steel.jpg

Note that the flange has screw holes so it can be mounted into the MDF, and the connection between the two would be stable. Also note that this flange is Closed so once in place it would seal off the sand contained in the pipe.

This one is probably a little expensive, but I have seen 3"&4" flange that are all heavy PVC (no metal) for less than $5.00. These particular flanges will work with both 3" and 4" pvc pipe. The 3" fits in the inside of the lower part of the flange and the 4" pipe fits on the outside.

I considered finishing mine (the ones I have planned) with either a faux stone finish or with a hammered metal ( dark copper) finish.

I was planning to put my sand in several ZipLok bags to reduce the mess.

Just a few thoughts.

Steve/bluewizard

Very cool idea on the PVC flanges! I think I will attempt to use those in my stands! Thank you :thmbsp:

 

[dmusgrave]

Were the speakers on carpet prior to the blocks?

Understand that this may seem like I'm doubting the effects, but I'm very analytical by nature and mostly my questions are trying to understand why the block (or whatever) might have an effect.

Yes, in both cases the speakers were on carpet. I'm sure the effect would be less noticeable on a hard floor, depending on how "hard" the floor was.

 

[dmusgrave]

Just something you can look at if you wish, but go to Home Depot and look at the solid yellow pine stair treads. They sell for about $10.00 each and are 4' x 12" x 1". If you cut four 8" pieces you will have four 8" x 12" bases. Then cut four 4" pieces and you will have four 4" risers, two per speaker stand. Home depot will do the cuts for you at 25 cents per cut. You will end up with 2 speaker stands having 8" x 12" bases with two 4" x 12" risers each. The yellow pine is finished wood and stains very nicely. Cheap way to go for some nice looking heavy speaker stands. Now you can do the same thing in solid oak but it'll cost you about $23.00 for the wood.

Looking at those prices "real" wood is probably cheaper than MDF and veneer in this application. I will probably look at using real wood :thmbsp:

 

[Tapehead47]

I have dozens of granite chunks that I used for landscaping. Now they're stacked up in the back yard and not in use. Most are rectangular about 6"x 12" and about 4" thick, but none are symmetrical. They are very dense.

My 12'x12' listening room has wood floors. I have to tread carefully when playing vinyl!

However, my Klipsch Fortes have the optional floor standing base. I have JBL 4311's on top of the Fortes.

I need to clean behind those speakers, anyway. While at it I'll lay down a couple layers of granite. Or would one layer do the job?

Where else could I use the granite?

 

[dmusgrave]

I have dozens of granite chunks that I used for landscaping. Now they're stacked up in the back yard and not in use. Most are rectangular about 6"x 12" and about 4" thick, but none are symmetrical. They are very dense.

My 12'x12' listening room has wood floors. I have to tread carefully when playing vinyl!

However, my Klipsch Fortes have the optional floor standing base. I have JBL 4311's on top of the Fortes.

I need to clean behind those speakers, anyway. While at it I'll lay down a couple layers of granite. Or would one layer do the job?

Where else could I use the granite?

I'd try it different ways, see if you can hear a difference. It looks like those of us who see an improvement from putting our speakers on stone and concrete have our speakers on carpted floors. That may be the "magic" element. I wonder if it would make any difference on your hard wood floors?

Don't forget to report back :yes:

 

[Zilch]

Understand that this may seem like I'm doubting the effects, but I'm very analytical by nature and mostly my questions are trying to understand why the block (or whatever) might have an effect.

The floor is a boundary, and as such reinforces the bass by 6 dB. To the extent that a plinth or stand separates the woofer from that boundary, the effect is reduced, as the speaker radiates more into a sphere as opposed to a hemisphere, i.e., 4-Pi versus 2-Pi loading.

With regard to the mids and highs, all drivers have directivity. Generally speaking, their maximum SPL with the design frequency response is on-axis. Elevating those drivers to listening height (or aiming them there) improves their perceived performance because they're playing to your ears rather than your kneecaps.... :yes:

 

[dmusgrave]

The floor is a boundary, and as such reinforces the bass by 6 dB. To the extent that a plinth or stand separates the woofer from that boundary, the effect is reduced, as the speaker radiates more into a sphere as opposed to a hemisphere, i.e., 4-Pi versus 2-Pi loading.

With regard to the mids and highs, all drivers have directivity. Generally speaking, their maximum SPL with the design frequency response is on-axis. Elevating those drivers to listening height (or aiming them there) improves their perceived performance because they're playing to your ears rather than your kneecaps.... :yes:

Zilch in English are you saying that a woofer sitting at basically the level of the floor floor has a 6 dB bump and the higher you get that woofer off the floor the lower that bump in dB goes? If so, that explains the loss of "boominess" and the increase in accuracy on the low end when sitting on cinder blocks. I knew it had something to do with interaction with the floor, but I'm not as bright as you, I just knew it sounded better :lmao:

When we, yes I said we, design my cabs, I'd like the woofer to be high enough off the floor to eleminate that hump. Pretty much like the http://audioheritage.org/vbulletin/showpost.php?p=112397&postcount=16 but with a taller "bottom" below the woofer. Would make for a bigger cabinet too, which you know turns my crank :thmbsp:

I understand getting the mids and highs up at ear height... had already made that decision :yes: Believe it or not, I'm actually getting a grasp on the on and off-axis response stuff

 

[Zilch]

Like this?

 

[dmusgrave]

Like this?

Closer! I want tall! I want big! I want lifetime keepers :yes:

I guess I actually need to do some measuring and see how high we can get the woofer while still keeping the horns at ear level :scratch2: Hopefully high enough off the floor to remove that hump :thmbsp:

 

[Tapehead47]

I'd try it different ways, see if you can hear a difference. It looks like those of us who see an improvement from putting our speakers on stone and concrete have our speakers on carpted floors. That may be the "magic" element. I wonder if it would make any difference on your hard wood floors?

Don't forget to report back

Didn't mention that my floors are carpeted OVER the wood. And the carpeting is cheap commercial stuff from Home Depot. But the room is a sectioned-off area of a shed that's reserved just for my santuary. It's air conditioned and has 'soundproof' insulation. (there ain't no such thing as 'soundproof' insulation).

After reading Zilch's post I'm not so sure it's worth the effort. Raising the woofers 4-8 inches would make a difference whether the speakers were placed on concrete or milk crates.

As it stands now, the mids and high freq horns are at ear level from my listening position. An experiment is in order, but perception my be skewed psychologically. A profound difference would be obvious, but a slight difference?

This weekend I'll give it a go. The area behind the speakers needs to be cleaned anyway! It's hard to get behind that pile of speakers and I need a good reason to do so. A report will follow.

Good Thread!

Rick


__________________

 

[VOT]

My JBLs are on marble slabs (JBL C56 tops) which are on plain laminated MDF stands about 10 inches off carpeted concrete basement floor. Bass is noticeably better than without the slabs. I assume it has something to do with reducing area of resonance at the bottom of the enclosure where the woofer is located. :scratch2: I just know it works.

 

[Zilch]

My JBLs are on marble slabs (JBL C56 tops) which are on plain laminated MDF stands about 10 inches off carpeted concrete basement floor. Bass is noticeably better than without the slabs. I assume it has something to do with reducing area of resonance at the bottom of the enclosure where the woofer is located. :scratch2: I just know it works.

You have increased the inertia of the stands by adding mass. The speaker cannot vibrate them so easily, so more bass energy is transmitted to the air by the woofers. Action ... reaction.

http://www.audiomisc.co.uk/cones/speak.html

 

[Damage]

Put the blocks on top of the speakers.

 

[Wedweb]

Didn't JBL have some speakers with marble on top? End tables?

Bo

 

[VOT]

Didn't JBL have some speakers with marble on top? End tables?

Bo

Yea. That is the C56 Dorian. I am using those tops at bottoms.

 

[dmusgrave]

An experiment is in order, but perception my be skewed psychologically. A profound difference would be obvious, but a slight difference?

I don't think the difference will be at all slight if your woofers are close to the floor now. 6db is one hell of a hump. If you think what you hear might be due to a placebo effect have your significant other or a friend A/B them in different arrangements.

Every time I try something new I make my girlfriend listen. She could care less about the gear but she loves music, and so far she's heard the same things I've heard when I've made changes... even when I went to heavier gauge speaker wire... and she's clueless about that sort of thing beyond hearing a difference in sound.

Keep in mind... all this coming from a guy who thinks an interconnect that costs more than 40.00 is snake oil :lmao: I guess these kind of tweaks intrigue me so much because a. they are measureable and b. I can afford them :lmao: