Concrete boots.

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Dave the bass
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Concrete boots.

Post by Dave the bass » Sun Apr 08, 2018 8:45 pm

Now this may come as a bit of a surprise but I've actually done a DIY-audio-related project.

I'd been experimenting with listening to a variety of loudspeakers out in the lovely but lively Conservatory for a while, we sit quite close to whatever's in use at the time because of the layout of the room and by experimenting with various blocks of wood and lashed together angle parts found I could get a very pleasant 'sound' and wider soundstage by angling some speakers back a little so the speakers 'fire' up a little towards the listeners on the Sofa.

So I thought I'd make something a bit less rickety than some of the wooden contraptions I'd temp lashed together whilst experimenting with angles and heights.

I had 2 bags of sharp sand that were leftover from a building project from 2 years ago, the bags were split and opened to the elements so 'nicely acclimatised' , read as wet and needed using up.
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After careful measuring, I made a mold from some scrap ply...
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..got mixing the sand a cement together in small manageable batches and filled up the mold...
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Messy work but rewarding...
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I sealed them using 2 coats of a PVA and water mix in case I wanted to paint them later and also to stop any loose sand or crete dust falling off 'em...
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And lo n behold.... ta dah!
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Sorted. Like. Pleased with them.
"'Occasionally phenomenal'"

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andrew Ivimey
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Re: Concrete boots.

Post by andrew Ivimey » Sun Apr 08, 2018 9:56 pm

Nope I don't understand... you've got some rather dull speakers and you've spent a couple of weeks and a great deal of clever creativity making then slightly better by making stands. The Romans invented concrete and some still ask....what did they ever do for us!!!?

I prefer the viticulture ... and the aqueducts.

Or did I miss something.
Philosophers have only interpreted the world - the point, however, is to change it. No it isn't ... maybe we should leave it alone for a while.

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pre65
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Re: Concrete boots.

Post by pre65 » Sun Apr 08, 2018 10:00 pm

I believe the Kray twins liked concrete. :lol:
People are like stained-glass windows. They sparkle and shine when the sun is out, but when the darkness sets in, their true beauty is revealed only if there is a light from within
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Re: Concrete boots.

Post by IslandPink » Sun Apr 08, 2018 11:15 pm

Good ! - nice preparatory work for the concrete bass horn that feeds into the conservatory.
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andrew Ivimey
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Re: Concrete boots.

Post by andrew Ivimey » Sun Apr 08, 2018 11:24 pm

Perhaps a whole re-design of the house...after all lets get priorities prioritised - ferget bricks - we want concrete.
Philosophers have only interpreted the world - the point, however, is to change it. No it isn't ... maybe we should leave it alone for a while.

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Re: Concrete boots.

Post by ed » Sun Apr 08, 2018 11:27 pm

Phillistines!
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Re: Concrete boots.

Post by simon » Sun Apr 08, 2018 11:40 pm

Can't believe no one's asked about your concrete mix Dave ;-)

Good effort. Did you use any aggregate or just sharp sand? It would explain why you got such good corners without arrises if you didn't.

I could ask if you used any shutter release agent, but I'd just be taking the mick. :-)

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Dave the bass
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Re: Concrete boots.

Post by Dave the bass » Mon Apr 09, 2018 11:20 am

andrew Ivimey wrote:
Sun Apr 08, 2018 9:56 pm
Nope I don't understand... you've got some rather dull speakers and you've spent a couple of weeks and a great deal of clever creativity making then slightly better by making stands.

Or did I miss something.
You may have missed summat.

Agreed, they may look 'dull' but they're not bog standard Celestion DL8s. I doped the mid/bass driver and covered the cone surface in Plasticote, removed the crossover and replaced it with a simple single R single C circuit to protect the tweeter (which is now a 1980's Audax HD100d25 unit as our-MrT has the Fostex HF horns on loan for a while in his ace OB project), the mid/bass unit runs full range. The cabinet I painstakingly sealed with silicone sealant to ensure no air leaks, there's no ports, its a totally sealed box, I went to town on the sealing gaskets too for the drivers, no leaks. The admittedly grot look cabinets are lined with steel plating that adds a lot of weight and mass to the cabinet. If you haven't glassed-over yet there's a pictureless thread here to explain how they came to be -> http://www.audio-talk.co.uk/phpBB3/view ... f=4&t=6708

...but now with newly made plywood gasket to allow Audax HF unit to fit. They look like this now...
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IslandPink wrote:
Sun Apr 08, 2018 11:15 pm
Good ! - nice preparatory work for the concrete bass horn that feeds into the conservatory.
Ha! I did think that whilst I was making the mold and searched for FR Concrete Horn speakers, I showed JTS some piccies of some behemoths. She was mighty impressed....and then realised what she'd just said and gave me a worrying look.... :) Heheheheheh,
simon wrote:
Sun Apr 08, 2018 11:40 pm
Can't believe no one's asked about your concrete mix Dave ;-)

Good effort. Did you use any aggregate or just sharp sand? It would explain why you got such good corners without arrises if you didn't.

I could ask if you used any shutter release agent, but I'd just be taking the mick. :-)
Dearest Simon! You're amongst chums here!

I didn't use any aggregate (as I didn't have any and this project had a budget of £0.00), so, only 'weathered' Sharp sand and Blue Circle General Purpose Cement (it was grey, not blue...) was used in a 2.5:1 part mix.

Mold release compound was Vaseline (petroleum jelly) that I cafefully rubbed onto every internal 'crete facing surface each time I used the mold.

I learnt a new word. 'Arrises'. Thank you :)
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Re: Concrete boots.

Post by Mike H » Mon Apr 09, 2018 2:50 pm

Good lord! :shock:
 
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Re: Concrete boots.

Post by ed » Mon Apr 09, 2018 3:25 pm

Dave the bass wrote:
Mon Apr 09, 2018 11:20 am
I learnt a new word. 'Arrises'. Thank you :)
could it be the same one that poor old Polonius got stabbed in?
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Re: Concrete boots.

Post by Dave the bass » Mon Apr 09, 2018 7:16 pm

Blimey! Polonius got stabbed in the Bum?
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pre65
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Re: Concrete boots.

Post by pre65 » Mon Apr 09, 2018 7:21 pm

Dave the bass wrote:
Mon Apr 09, 2018 7:16 pm
Blimey! Polonius got stabbed in the Bum?
They don't like it up em. :lol:

Any fool knows this,

arras - a wall hanging made of a rich tapestry fabric, typically used to conceal an alcove.
People are like stained-glass windows. They sparkle and shine when the sun is out, but when the darkness sets in, their true beauty is revealed only if there is a light from within
Dr Elisabeth Kubler-Ross

G-Popz THE easy listening connoisseur. (Philip)

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Dave the bass
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Re: Concrete boots.

Post by Dave the bass » Mon Apr 09, 2018 7:31 pm

"'Occasionally phenomenal'"

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Re: Concrete boots.

Post by simon » Mon Apr 09, 2018 10:19 pm

Even better effort Dave :-D. Though technically what you have there is more a grout than a concrete.

(Vegetable oil might have been cheaper than vaseline ;-). Might not have released as well though.)

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Ali Tait
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Re: Concrete boots.

Post by Ali Tait » Mon Apr 09, 2018 10:53 pm

Ah, the release of Vaseline..
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