Concrete Audio Speakers...Speaker Enclosures made out of Concrete ?..

They do sound quite bad to me. 

Very very small concrete speakers SOUND TEST...put some GOOD headphones on and listen to this.. 
 

  
https://www.youtube.com/watch?v=BuQK82Fwb1U&t

here's the videos on how to make your own concrete speakers 
 
https://www.youtube.com/watch?v=xCPMxgY_ZN4
 
 https://www.youtube.com/watch?v=LsegJY347dE&t=126s
  
https://www.youtube.com/watch?v=8XLqTvL51t4
 
 https://www.youtube.com/watch?v=CIGmRkhFjIQ&t=78s

"...the alkaline that constantly seep out of the concrete would cause any finish applied to them to peel off."

Having "any finish" on them is blasphemy. We, the purists, would want them in "natural concrete".

Has anyone heard these?  I would find opinions intriguing.  I moved my system from our main room which has polished concrete floors into another area where I put down an engineered product over the concrete with immediate improvement in sound quality.  Just trying to think about how to abstract one into another.  Not sure.  I suspect the book shelf on stands vs the floor standers vs the wall mounts would all sound completely different given the contact points but uncertain.  Very interesting concept. 

Rauna from Norway or Sweden made transmission line speakers made from Concrete about 40 years ago, they did sound pretty good for their time. Danish Advance Loudspeakers also made concrete enclosures back then. Both companies used a fiber filled concrete and  the walls were about 2" thick,  so very little "ringing". I'ts all in the implementation. The biggest issue both had was the the alkaline that constantly seep out of the concrete would cause any finish applied to them to peel off. I think this was the main reason they quit doing it.

Good Listening

Peter

How to make your own concrete speaker boxes...five part video
 
 https://www.youtube.com/watch?v=kf2zkd5SAZU&list=PLycL7IZk1IZk1IfKmUbsd4870ooVKHcIhdt  
 

 

What about acora's granite speakers? Lot of people swear by them!

https://www.acoraacoustics.com/src-1

So if I design a piece of junk speaker but enclose it in concrete what will make it sound better?  Lets 

More feedback..

https://www.theaudiobeat.com/blog/concrete_audio_n1.htm

https://www.youtube.com/watch?v=pk0H-xahxA4

Could’ve sworn thiel had some kind of a concrete driver. 

Everybody is saying no good...but who here has heard them ?

Ideas, ideas, ideas!  This leads me to think of horn speakers.  Have someone cup their hands around their mouth and talk to you - it doesn't sound ANYTHING like them talking to you without their hands cupped around their mouth!!!  WHY, WHY would you want that effect in your hi-end audio system???  TOTALLY UNNATURAL!!  Horns are fine if accuracy is not a requirement or you just want to fill an auditorium with sound - but, to me, NOT for music!  Another concept from the past that has fueled a company to be a "great seller" is Amar Bose and his direct-reflecting speaker concept.  When have you EVER been to a concert/music presentation where the performer(s) and their equipment were turned around to face the back of the stage, save for one or two pieces of equipment for direct play to the audience - NEVER!!!  We won't get into the ridiculous 901 speaker design here! the unconscienable joke that it was!  But yet Bose is a top-selling brand!      Sorry for the divergent rant - all this talk about speaker cabinets set me off!  and these are IMHO only!

BAD idea it will sound like bricks  are you joking?

I tried concrete, and the sound was weighty and too hard. I wanted something more airy. So now trying styrofoam.

I once saw a demonstration about concrete boat hulls. At one point the speaker struck the side of the concrete hull (it was an unfinished boat out of the water) with a pipe or bar and it rang like a giant bell. We actually sailed a concrete hull sailboat. Beautiful boat.

To say one material is always superior to another and another material is always inferior is an over simplification of what's involved in the designing of any product. The implementation is just as important as the material used.

For example, some people here argue that aluminum is the best material to use for speaker enclosures. Which alloy are you referring to? 6061, 2024, 7075...? What cross section? What shape? Pick up a piece of 0.5" thick 7075 and strike it with a bar, it will ring big time. I'm not saying aluminum isn't good for use in speaker enclosures, it can be great if used properly. BTW, properly designed aluminum extrusions can be economical and practical for speaker enclosures if you sell enough product.

Its not a question of practicality. They sound bad. 

Concrete, granite, cast iron... Companies try, but really, how practical is this?

You also have Rauna. Very good but not very practical to ship somewhere.

https://rauna.com/

NO! Too much resonance!

No. They will ring like a bell. And not thick enough.