I've been searching for some designs with PVC sewer pipe, and would be interested in any designs and listening experiences. In terms of options we have commonly available (all internal measurements):
110mm - for CHR-70, Alpair 7, Fostex 103E etc
160mm - for JX92S, Alpair 7, Fostex 168E etc
200mm - for Alpair 12, Fostex 208E etc
There are various accessories as well - T junctions, 90 deg. bends, stoppers, access pipes etc which would facilitate a speedy construction.
The other interesting possibility is to put a pipe within a pipe and fill the space between with sand. So 110mm inside 160mm, 160mm inside 200mm, 200mm inside 250mm. Should be pretty inert!!
So how to proceed with this? I can't see it being possible to taper the pipe, so bass reflex is an obvious option. But what could I do in terms of a tuned pipe - ideas?
andy
110mm - for CHR-70, Alpair 7, Fostex 103E etc
160mm - for JX92S, Alpair 7, Fostex 168E etc
200mm - for Alpair 12, Fostex 208E etc
There are various accessories as well - T junctions, 90 deg. bends, stoppers, access pipes etc which would facilitate a speedy construction.
The other interesting possibility is to put a pipe within a pipe and fill the space between with sand. So 110mm inside 160mm, 160mm inside 200mm, 200mm inside 250mm. Should be pretty inert!!
So how to proceed with this? I can't see it being possible to taper the pipe, so bass reflex is an obvious option. But what could I do in terms of a tuned pipe - ideas?
andy
Here are some illustrations of what's available:
uPVC Sewer & Drainage Systems | Marley Pipe Systems - download Marley uPVC Sewer & Drainage pdf
160mm Junction - Equal Junction - Double Socket - 87 ½ Degree - spigot tail - 160mm Couplings Bends and Junctions - Drainstore
eBay UK Shop - jumbo building supplies:
andy
uPVC Sewer & Drainage Systems | Marley Pipe Systems - download Marley uPVC Sewer & Drainage pdf
160mm Junction - Equal Junction - Double Socket - 87 ½ Degree - spigot tail - 160mm Couplings Bends and Junctions - Drainstore
eBay UK Shop - jumbo building supplies:
andy
If you search hard enuff Andy you will find quite a few. Here are 2:
Laying Pipe with Audio Lego
the toobs Mk 1
The 1st describes a method of tapering a PVC pipe,
And there is Linkwitz Pluto as well.
I have a piece of 300mm pipe here for an El Pipo style woofer (with a pr of isobarik 12")
dave
Laying Pipe with Audio Lego
the toobs Mk 1
The 1st describes a method of tapering a PVC pipe,
And there is Linkwitz Pluto as well.
I have a piece of 300mm pipe here for an El Pipo style woofer (with a pr of isobarik 12")
dave
here's something rather oddball - - Sapkowski's patent (examiners missed Fulmer and Karlson as prior art)
I only had one piece of pvc for experiment - IIRC there was quite a bit of midrange emanating from the hole array!
High Efficiency Speaker Asylum - holey Sapkowski - freddyi - October 23, 2007 at 15:59:04
I only had one piece of pvc for experiment - IIRC there was quite a bit of midrange emanating from the hole array!
High Efficiency Speaker Asylum - holey Sapkowski - freddyi - October 23, 2007 at 15:59:04
To tune the pipe, I suspect a 3" pipe out the side of an 8" pipe would look pretty good - need some pretty accurate cutting though...
Hi Dave,
I've been looking into this some more. I like my idea of 2 coaxial cheap PVC tubes with sand in the middle. An alternative would be the high pressure type PVC tubing = walls from 7mm to 12mm. But this gets expensive, alas. Sand is cheap!
I'm looking at suppliers here in the UK. Debating how to mount the forward pointing speaker - I can see a few options here! 110mm square hopper looks good - gives you a nice square front tapering down to 110mm pipe - very easy to bolt on a baffle. I'm thinking tall and thin, so thinking of a t junction 2/3 way up rather than a 90 degree bend at the top. Early days! But I'm getting restless to go out and get some tube to play with. Rob Sampson calls it "audio Lego"!
andy
I've been looking into this some more. I like my idea of 2 coaxial cheap PVC tubes with sand in the middle. An alternative would be the high pressure type PVC tubing = walls from 7mm to 12mm. But this gets expensive, alas. Sand is cheap!
I'm looking at suppliers here in the UK. Debating how to mount the forward pointing speaker - I can see a few options here! 110mm square hopper looks good - gives you a nice square front tapering down to 110mm pipe - very easy to bolt on a baffle. I'm thinking tall and thin, so thinking of a t junction 2/3 way up rather than a 90 degree bend at the top. Early days! But I'm getting restless to go out and get some tube to play with. Rob Sampson calls it "audio Lego"!
andy
Around about 19660 Rex Baldock designed a range of speakers called the tricolumn. Google "Haskelling".
Basically a Voigt type tapered column, they consisted of a vertical tube, open at the floor end, with speaker mounted horizontally at the top end. Inside was another tube, glued at the top, and to one side of the larger pipe, roughly 60% of its OD, and two thirds of its length. This was open at the speaker end, and closed at the lower end. Effectively this gave a taper, consisting of the small pipe, (circular), the area between the two pipes, (crescent),then the large pipe, (circular), with the speaker mounted approximately one third from the closed end taking into account the effect of the floor at the open end. A reflector could be added at the top if desired.
It was mainly designed for speakers of the Super 8 type. Approx size for that unit 9" OD, 36" high. He tried a number of units, including a lowther PM6 in it.
I'm sure using MJK calcs plus more modern units, an interesting and WAF design could result.
Basically a Voigt type tapered column, they consisted of a vertical tube, open at the floor end, with speaker mounted horizontally at the top end. Inside was another tube, glued at the top, and to one side of the larger pipe, roughly 60% of its OD, and two thirds of its length. This was open at the speaker end, and closed at the lower end. Effectively this gave a taper, consisting of the small pipe, (circular), the area between the two pipes, (crescent),then the large pipe, (circular), with the speaker mounted approximately one third from the closed end taking into account the effect of the floor at the open end. A reflector could be added at the top if desired.
It was mainly designed for speakers of the Super 8 type. Approx size for that unit 9" OD, 36" high. He tried a number of units, including a lowther PM6 in it.
I'm sure using MJK calcs plus more modern units, an interesting and WAF design could result.
I was actually ruminating on a "green" speaker. If I had a pipe within a pipe and sand in between, I could plant nice flowers and plants in the sand at the top. I could have a T junction further down and a cap on the top of the pipe, but should leave room for a nice roof of vegetation - sort of a thatched roof effect..... think of the WAF!!
andy
andy
I've fund a nice website in the UK which looks good value. Current thinking is to use 160mm pipe. T junction triple socket to mount the speaker unit forwards, cap on top and plain pipe going down, then some sort of base. This could be enclosed in a square box section with sand in between. Cost for a pair of these - pipe plus T plus cap on top - is £71.10 plus VAT.
Given the above I'm thinking bass reflex, and estimating about 21 litres. Drawback with this is that something like a Jordan JX92 or a Alpair 10, which fit into a 160mm pipe, don't really require 21 litres. An Alpair 12 which would be nice doesn't fit into a 160mm pipe! Back to the drawing board, but I smell a very non-resonant enclosure here and quick to make - no need for internal bracing etc. Just have a top which can be unscrewed to have access to the interior.
andy
160mm diameter Pipe and Fittings - Building Supplies R Us
Given the above I'm thinking bass reflex, and estimating about 21 litres. Drawback with this is that something like a Jordan JX92 or a Alpair 10, which fit into a 160mm pipe, don't really require 21 litres. An Alpair 12 which would be nice doesn't fit into a 160mm pipe! Back to the drawing board, but I smell a very non-resonant enclosure here and quick to make - no need for internal bracing etc. Just have a top which can be unscrewed to have access to the interior.
andy
160mm diameter Pipe and Fittings - Building Supplies R Us
did this years ago before I knew much about TLs, could be refined considerably:
http://www.diyaudio.com/forums/multi-way/36540-karlson-slotted-pipes.html
The mouth has a Karlson slot, the result wasn't bad considering I didn't really have a clue what I was doing, I intend to re-do these with better drivers & better science one day...
http://www.diyaudio.com/forums/multi-way/36540-karlson-slotted-pipes.html
The mouth has a Karlson slot, the result wasn't bad considering I didn't really have a clue what I was doing, I intend to re-do these with better drivers & better science one day...
These guys have been designing pipe speakers since the 1980's. Have look at their site to generate some ideas:
Hawk High End Tube Loudspeakers
I have never made anything like these but they look neat!
Cheers, Marco
Hawk High End Tube Loudspeakers
I have never made anything like these but they look neat!
Cheers, Marco
Attachments
I bought 4x 8" full range driver on ebay for £3 ea with postage, and was experimenting with using traffic cones as rear tapering tubes.
In an effort to partly imitate the B&W nautilus tapering tubes (albeit on a next to free budget)
The small cones fit an 8" driver almost perfectly and the large ones a 12" woofer. The ends are open, so can be closed, stuffed or extended.
I still haven't got round to getting any testing equipment, but the basic project cost under £15 and sounded pretty good.
Has anyone else tried this, or seen it done?
In an effort to partly imitate the B&W nautilus tapering tubes (albeit on a next to free budget)
The small cones fit an 8" driver almost perfectly and the large ones a 12" woofer. The ends are open, so can be closed, stuffed or extended.
I still haven't got round to getting any testing equipment, but the basic project cost under £15 and sounded pretty good.
Has anyone else tried this, or seen it done?
There's some more ideas and links over on this thread: http://www.diyaudio.com/forums/multi-way/93527-pvc-pipe-speaker-ideas.html