Concrete speakers

[Malcolm T]

I am curious, many years ago these seemed all the rage and there were even articles about DIY on them. Now it appears they are back again and at great expense !. So what's so special about them other than they won't resonate as much as wood, the hype and they cannot be recycled?

I have never heard anything from cement speakers.

[vinrads]

You must be psychic Malcolm, I was discussing the very same subject with a friend who restores Juke boxes and wondered how to get better sound from them. I suggested a modern speaker, have you seen the price of some of the 12" speakers! I also mentioned about the concrete speaker enclosure back in the day, ports etc.

Mick.

[dave walsh]

There are designs in Practical Wireless from the sixties. Hi Fi was costly and the modern technology to drive relatively small, portable, sealed boxes with high wattage didn't really exist. You needed something substantial to improve things. A Radiogram was expensive and maybe old fashioned. Building a concrete or brick corner enclosure [or two] was a cheap option and was seen as a desirable modern home improvement not a monstrosity. You could knock up a wooden former with nails sticking out of the frame to secure the mixture.

For those who wanted something simpler, less permanent and perhaps more domestically acceptable a design based on Clay pipes [available now probably at the builders merchants] evolved. There was a commercial conversion kit available [get your own 3' pipe though]. As I recall, an 8"? speaker would be mounted facing down the pipe [from the top] which was raised at the base to allow the audio out! Both types were regarded as producing a good sound but not everyone went to that sort of trouble for a variety of reasons. Of course fixed or portable corner cabinets had been produced in wood previously. I think the use of materials with a greater mass was primarily aimed a better bass reproduction!

Dave W

[M0FYA Andy]

I recall some designs installed the speaker in the chimney, but I guess stereo scuppered that idea!

Andy

[Herald1360]

Perhaps not if you converted your old living/dining rooms into a "through lounge" when you had the central heating installed to take advantage of cheap North Sea gas.

[John10b]

Fixing Loudspeakers into walls was in fashion way back, I don’t know how many were actually fitted, does any one actually know, and is it done today?
Cheers
John

[Herald1360]

More likely to be in ceilings, for muzak now.

[dave walsh]

There was one chap who built a flared horn design that occupied each alcove. It began with the driver unit at top left and right in each side of the fireplace, curving down, widening and opening up into a "throat" that reached the floor at the full width. It then faced down into an opening to the space below. I can't recall if that was in concrete or brick but it may have been

I don't know if he was married or what the neighbours thought either I'm not sure what sort of amp he used but it may not have been that high wattage as the horn principle can be very efficient [but not usually that domestically practical]. It's the same with cabinets. A 5' 6" [square] baffle board will reproduce the full frequency range from an 8" spkr but where do you put it or both of them? It's bad enough with a pair of Quad electrostatics!

Dave

[ajgriff]

Originally Posted by John10b

Fixing Loudspeakers into walls was in fashion way back, I don’t know how many were actually fitted, does any one actually know, and is it done today?

Sounds like the perfect way to destroy neighbourly harmony. A bit like fixing TVs with rear facing speakers to party-walls. I speak from bitter experience.

Alan

[dave walsh]

Yes and that's very common today Alan but my recollection is that volume levels were lower back then and people were less aggressive/self centred. I built speakers into the alcoves in my first terraced home [wood not concrete-the spkrs that is!] as a part of the units but I actually went into the neighbours house to check what volume might become a nuisance and asked them to let me know if there was a problem. They were very appreciative and I knew what the practical limit was a likely to be. Not so easy these days I know!

Dave

[dave walsh]

Yes I mentioned PW in post 3* Malcolm. I will look for the issue! I don't think there was a "cement sound" as such. A large mass and weight was usually superior whatever the material ie the quality of large and heavy Radiograms! As you say, it's as much about being trendy as anything else now-like the people who bought vinyl records as decor [when they didn't have a record player] a couple of years back! I've an LG TV from 1996 [£850 half price] with a potential cascade fault that needs fixing. It has a [then] vast 32" 16:9 CRT screen and is very heavy. If there's any more left [probably unlikely] they may be the new Radiograms in the future. My point is that the [now] inconvenient size and weight produced really good sound

Dave

[Trevor]

Another way was sand filled baffles very heavy very dense and non resonant I had 2 15 " Wharfdales superb with 8" mids and kef 15 ,s for top
High Fidelity Stoke on Trent circa 1970
Trev

[Richard_FM]

I remember Richer Sounds suggesting that you fill hollow metal speaker stands with sand or lead shot to deaden the vibrations.

[ajgriff]

Fullers earth cat litter works really well too.

Alan

[raditechman]

In my Mullard 5/10 days I used some home made speaker columns (sewer pipes) they performed well, the sound from them was however too omni-directional and I replaced them with 2 Leak sandwich speakers to get a better stereo presence. I am still using the Leak sandwich speakers!
The concrete column speaker design I used is here.http://ukhhsoc.torrens.org/makers/Wh...lans/Page2.gif

John

[Malcolm T]

Very interesting stuff, i cannot believe people wanting vinyl records as decor
Sounds a bit twee to me LOL.
Concrete speakers are not what i would choose i think out of tradition i would choose wood but then i have never heard concrete ones .
yes it is all about density and resonance and resonant lengths, a bit of a complex world speaker design i think not to mention the material the speakers are made from and the the room, the decor and the floor material ie wood or concrete.
I,m pretty certain PW ran a story or two on concrete speakers.
I suppose if some lengths of re-bar were imbedded in the moulding one could have instant legs or a loop at the top to hang them from the wall .
I think i will stick with my Goodmans.
Volume levels did start to go up and some people filled the street with their particular brand of sound and it was,nt very nice when trying to get some rest at the weekend and it used to go on for hours and hours.

[terrybull]

This takes me back. I recall visiting a house where the occupier had built vertical speakers from clay pipe. I don't recall the details but he gave me a demo. They were awful. Muffled and hollow.

[dave walsh]

It's true about the decor Malcolm. The staff at Fopp Records in Manchester told me and it's confirmed elsewhere! Very sadly, the shop has now closed

Dave

[Malcolm T]

Well fads come and go , never heard of fopp records i suppose it was an Aladdins cave to vinyl lovers . I used to go to one in north west London many years ago and the LP and 45 record covers were all over the walls, dont know the name somewhere in a back street up Euston way.

Speakers in a chimney, wonder if he was married ?.

So Vinrad , are going to knock up some muck and make some cement speakers then?.

The other thing is air pockets , you,ll need a vibrator to get them out.
Well its satisfied my curiosity over cement speakers , i,m sticking to a recyclable material called wood .

[G6Tanuki]

"Sewer-pipe" speakers were very much a thing in the 1960s; one of my cousins used one as what we'd these days call a subwoofer - he took the 'difference' signal from his stereo amplifier's output and fed it through a low-pass filter then to another amplifier [push-pull 6L6] and thence to a sewer-pipe speaker laid horizontally behind the intended listening-position.

The Animals' "House of the Rising Sun" sounded great on it!