Hello everybody,
A friend is using a tqwt or Voigt enclosure for his loudspeaker. But now he decide that it will sound better if it is raised about 20 centimetes above ground. We did have the following idea. We will attach 3 or 4 hollow perforated pipes to the bottom of the enclosure. We will make a box ( wood or thin metal , thin metal like stainless steel 1.5 mm i can make myself, maybe it will ring more then 12 mm of wood but this will be damped immediately by the the sand? ! ) a little bit bigger then the floor dimension of the speaker with a height about 30 centimeters and fill it with sand for twenty centimeters. Then place the cabinet into the box. The pipes will secure the loudspeakers and will transmit the vibrations of the cabinet into the sand. The pipes will not touch the bottom of the sandbox. However the bottom of the loudspeaker will touch the sand and the first ten centimeters will be buried in the sand completely. So after putting in the first 20 centimeters of sand , we will put in the loudspeaker and then fill the reaining 10 centimers with sand.The bottom of the enclosure is not to big. But i think most of the vibration will be in the centre of it, so there must be a pipe for sure?! In the past i did read that if you want the sand to do its function you must NOT use a thick cabinet otherwise the vibration will continue to travel through the cabinet itself and not disappear into the sand. I think some of the ideas can also be used to make a '' thing'' for your turntable. It has been done in France in 1981. Anyone has an idea to make it better? Thanks, Ed
A friend is using a tqwt or Voigt enclosure for his loudspeaker. But now he decide that it will sound better if it is raised about 20 centimetes above ground. We did have the following idea. We will attach 3 or 4 hollow perforated pipes to the bottom of the enclosure. We will make a box ( wood or thin metal , thin metal like stainless steel 1.5 mm i can make myself, maybe it will ring more then 12 mm of wood but this will be damped immediately by the the sand? ! ) a little bit bigger then the floor dimension of the speaker with a height about 30 centimeters and fill it with sand for twenty centimeters. Then place the cabinet into the box. The pipes will secure the loudspeakers and will transmit the vibrations of the cabinet into the sand. The pipes will not touch the bottom of the sandbox. However the bottom of the loudspeaker will touch the sand and the first ten centimeters will be buried in the sand completely. So after putting in the first 20 centimeters of sand , we will put in the loudspeaker and then fill the reaining 10 centimers with sand.The bottom of the enclosure is not to big. But i think most of the vibration will be in the centre of it, so there must be a pipe for sure?! In the past i did read that if you want the sand to do its function you must NOT use a thick cabinet otherwise the vibration will continue to travel through the cabinet itself and not disappear into the sand. I think some of the ideas can also be used to make a '' thing'' for your turntable. It has been done in France in 1981. Anyone has an idea to make it better? Thanks, Ed
Your stand concept sounds very interesting but I'm afraid I'm a bit dumb and have difficulty visualizing exactly what you mean.
Is there any chance you could attach a simple sketch?
Is there any chance you could attach a simple sketch?
Hello i think i didn't manage to do it. I will try visualise it like this. My speaker enclosure it an oilplatform that is partly underwater ( so including the working space ) but now it is an aquarium filled with sand instead of water. You surely see it now, Ed
I think it should sound good. A combination of having the speaker at the right level, holding it still in space and isolating it from the floor means that it should work pretty well on all floor surfaces.
Don't forget to send us a report and photos when it's finished.
Good luck
Don't forget to send us a report and photos when it's finished.
Good luck
Hello, A little addition. The french people did '' steal '' some of their ideas from tables that are used for balances for very small weights. They will make the table twenty till hunderd times more heavy then the balance. In the end they did have a weight between 250 and 300 kilogram. The weight of the turntable was around 60 kilogram. Maybe i will try to find a forum in France and explain my idea to get some new ones. I think it will surely work but maybe someday there will a new Einstein who will say you should have done it like this. To prevent this i did post this message. Thanks in advance, Ed
Very interesting to use sand as a damping material. The perf pipes are a great way to stabilize. Will there be enough surface area to keep the speaker from sinking over time?
Also, one thing to watch out for: If the speaker boxes have an opening near the floor, then raising by 20 cm could take away any extra low freq.
🙂ensen.
Also, one thing to watch out for: If the speaker boxes have an opening near the floor, then raising by 20 cm could take away any extra low freq.
🙂ensen.
Eduard,
It should work well. Some tips would be to make the base as large as possible (floor area, you need mass) and screw a baseplate to the bottom of the speaker before you insert it into the sand. The baseplate should not touch the sides or bottom, and will act as a stabiliser, like a keel on a yacht. Make sure the sand is very clean and dry; you don't want living things in it. I'd also use a coarse builder's sand below the basplate, and as fine as I could above it.
Cut a top plate that will sit on the top of the sand to stop kids/animals messing with it, and you can use a fine foam like is used in weathersealing around the edges to make sure nothing leaks.
I build TT stands this way with about 0.75 cu metre of sand and a complex 'keel' arrangement. Rock solid and very well damped.
It should work well. Some tips would be to make the base as large as possible (floor area, you need mass) and screw a baseplate to the bottom of the speaker before you insert it into the sand. The baseplate should not touch the sides or bottom, and will act as a stabiliser, like a keel on a yacht. Make sure the sand is very clean and dry; you don't want living things in it. I'd also use a coarse builder's sand below the basplate, and as fine as I could above it.
Cut a top plate that will sit on the top of the sand to stop kids/animals messing with it, and you can use a fine foam like is used in weathersealing around the edges to make sure nothing leaks.
I build TT stands this way with about 0.75 cu metre of sand and a complex 'keel' arrangement. Rock solid and very well damped.
Hello the pipes are only used to secure the speakerenclosure in the sand. The speakerenclosure itself will be burried in the sand for about 10 centimeters, the bottom of it will touch the sand completely so it cannot sink any further. We want the pipes to also have the function of transmitting vibrations from the enclosure into the sand. Maybe we will use a pipe with some holes near to the bottom of the enclosure otherwise there will be no sand inside but air. Maybe a reason to use big l-shaped corners. The best of course would be to build a completely new cabinet and double the two sides and fill them with sand. But the ones that are used now have a cork outside just like my Altec Vot ( there is a picure somewhere on this forum ) and my friend don't want to destroy it. With a Voigt enclosure the opening will act like a kind of horn, but i think that the sandbox will be seen as part of the floor a little bit. But the sound will surely be less boomy because of the isolation. But we can change the sound in the lower region by changing the seize of the port. While typing i did get an idea. I can make those angles myself at the company. I can make a few in the shape of a rectangular arcade. This will give a big '' contactarea '' between the enclosure and the sand. We will glue and screw to give the maximum transmission of vibration. It will surely change the sound when everything is finished we will send a personal message to everybody who did react to this subject. Then we will try to do something similar for his Scheu turntable. Thanks, Ed
Hello Brett,
We did decide to not use something in a horizontal shape because it will be dificult to realize a perferct contact between the bottom side of this plate and the sand because the sand will surely be moving. I think by using corners in vetical direction we can make a good construction. The important thing is to transmitt the vibration from the enclosure into the sand. A really big box would be ideal but his girlfriend will not accept it. My turntable is inside a cupboard in a rack that has a shape of an oilplatform but there is no dirct contact with the floor but is supported in everycorner to a brickwall. Every individual platform can surely support 100 kilo or more. My future Scheu turntable will have a weight about 25 kilo so i can surely manage to add a few kilos of sand over there. Now i use a seismic sink for my Rega cd-transport but i have to inflate it every 24 hours. But here i cannot add a big heap of sand otherwise i cannot open its drawer anymore. Maybe if the Scheu is functioning that will not be a problem. Thanks, ed
We did decide to not use something in a horizontal shape because it will be dificult to realize a perferct contact between the bottom side of this plate and the sand because the sand will surely be moving. I think by using corners in vetical direction we can make a good construction. The important thing is to transmitt the vibration from the enclosure into the sand. A really big box would be ideal but his girlfriend will not accept it. My turntable is inside a cupboard in a rack that has a shape of an oilplatform but there is no dirct contact with the floor but is supported in everycorner to a brickwall. Every individual platform can surely support 100 kilo or more. My future Scheu turntable will have a weight about 25 kilo so i can surely manage to add a few kilos of sand over there. Now i use a seismic sink for my Rega cd-transport but i have to inflate it every 24 hours. But here i cannot add a big heap of sand otherwise i cannot open its drawer anymore. Maybe if the Scheu is functioning that will not be a problem. Thanks, ed
Hello, my friend just did finish a wooden sandfilled plinth for his Scheu turntable. The height of this plinth is only 5 centimeters but the difference was very big! Now he is thinking about building completely new tqwt cabinets which have the left and right side and the rear side sandfilled. The inner cabinet will be made 18 mm ply and the outside will be a little thinner based on articles in French magazines in the early eighties. Because of the wood that connects the two sides on the inside of the cabinet we think we can get get away with one inch of sand on the two sides. We think it is a good idea to make a connection between the magnet and the rear side, this will help the vibration of the loudspeaker to be transported into the sand. So for the rear side maybe 2 inches of sand will be the option. Of course he doesn't want the 110 kilogram weight of my sandfilled VOT's. Anyone this use this approach in a tqwt cabinet. Thanks a lot, Ed
I used sand between the inner and outer enclosure on my original Seventh Veil System IV.eduard said:
You have to bear in mind that the majority of vibration transferred to the cabinet is mechanical vibration from the drive unit itself, rather than any air-born sound waves. Design the enclosure accordingly and you could have a winner.
Dont know about that steve? On my horns the mouth vibrates MUCH greater than the baffel, of course the baffel is 3" thick.
ron
(if a little is good then a whole lot must be better LOL)
ron
(if a little is good then a whole lot must be better LOL)
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