Greetings everyone. I'd like to share my story about this project. I was looking to start building speakers, and looking for some cheap drivers to start playing with different types of enclosures. One day I stumbled upon two old closed speakers used for vinyl turntables. I knew they sounded really bad and I was going to throw them to the garbage bin, but I thought I could play with the drivers a bit. I was surprised they even worked since the speakers were left in the rain.
The quickest and cheapest enclosure I could set up was made from PVC pipes. I've seen some projects using them and I thought it's crazy, but if it didn't work, I would lose nothing (I could reuse the pipes anyway).
I started experimenting with different parts until I came to a sort of ported tower. Got all the parts assembled and put some stuffing behind the driver and where the port is.
I wasn't expecting anything good, but I was amazed by how good it sounded.
The drivers are very old, probably made in the 80s or before. The only thing I know about them is that the cone is 3.5 inches and that their impedance is 4 ohms. The paper cone is rather stiff, and the surrounding ring is made of rubber. I think they're pretty stiff because of the ring.
But the sound reproduction is pretty good. They're mid centered, of course, but they extend pretty well into the highs, and with these enclosures, I'm amazed by how low the bass goes. It's not earth-shaking, obviously, but it's a very snappy, musical bass, and it doesn't go away at low volumes. Even the drum'n'bass sub-bass is there!
The soundstage is nothing that I've ever encountered until now. You can really hear the placement of instruments and the separation of sounds. It's very lively, like the band is there with you. 80s music sounds very good on them, those plate reverbs and the drums!
They do go loud, but again it's a sort of musical loudness, not that pure power you get with big speakers. They seem to "scream" and fill the room quite nicely.
Well, now that I've bored you enough, some technical bits and pictures
The pipe is 110mm in diameter, and the port is 50mm. The height is about 90cm. I've eventually stuffed the lower part (under the port) and the back of the driver. The whole thing here is about "tuning" the pipe, as the length increases, the resonant frequency goes lower. I didn't try a longer pipe, but I tried a shorted one, and it sounded, well, like a pipe.
(the pipe is originally grey, as seen in the last pics, but I've painted it with that matte black paint. The surface of the pipe is shiny and the paint scratches easily - that's the downside)
I wanted to cover the driver with a black textile material, but I thought it kills the highs and the liveliness of the music. It looks a bit ugly without it, but the music is more important!
It may not be the fancy wooden enclosure, but it's certainly an interesting project to try.
The quickest and cheapest enclosure I could set up was made from PVC pipes. I've seen some projects using them and I thought it's crazy, but if it didn't work, I would lose nothing (I could reuse the pipes anyway).
I started experimenting with different parts until I came to a sort of ported tower. Got all the parts assembled and put some stuffing behind the driver and where the port is.
I wasn't expecting anything good, but I was amazed by how good it sounded.
The drivers are very old, probably made in the 80s or before. The only thing I know about them is that the cone is 3.5 inches and that their impedance is 4 ohms. The paper cone is rather stiff, and the surrounding ring is made of rubber. I think they're pretty stiff because of the ring.
But the sound reproduction is pretty good. They're mid centered, of course, but they extend pretty well into the highs, and with these enclosures, I'm amazed by how low the bass goes. It's not earth-shaking, obviously, but it's a very snappy, musical bass, and it doesn't go away at low volumes. Even the drum'n'bass sub-bass is there!
The soundstage is nothing that I've ever encountered until now. You can really hear the placement of instruments and the separation of sounds. It's very lively, like the band is there with you. 80s music sounds very good on them, those plate reverbs and the drums!
They do go loud, but again it's a sort of musical loudness, not that pure power you get with big speakers. They seem to "scream" and fill the room quite nicely.
Well, now that I've bored you enough, some technical bits and pictures
The pipe is 110mm in diameter, and the port is 50mm. The height is about 90cm. I've eventually stuffed the lower part (under the port) and the back of the driver. The whole thing here is about "tuning" the pipe, as the length increases, the resonant frequency goes lower. I didn't try a longer pipe, but I tried a shorted one, and it sounded, well, like a pipe.
(the pipe is originally grey, as seen in the last pics, but I've painted it with that matte black paint. The surface of the pipe is shiny and the paint scratches easily - that's the downside)
I wanted to cover the driver with a black textile material, but I thought it kills the highs and the liveliness of the music. It looks a bit ugly without it, but the music is more important!
It may not be the fancy wooden enclosure, but it's certainly an interesting project to try.
I think you chose well by going with PVC! I started my PVC Pipes project as a full range and quickly found myself going the multiway route with a quarter wave TL pipe for the woofer and one for the mid/tweeter pipe designed using the Martin King quarter wave design tool. My full range pipes sounded amazing, but I really just wanted to keep building ...
Here's a picture of my pipes under construction...
...Here's a picture of my pipes under construction...
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They're huge!I think you chose well by going with PVC! I started my PVC Pipes project as a full range and quickly found myself going the multiway route with a quarter wave TL pipe for the woofer and one for the mid/tweeter pipe designed using the Martin King quarter wave design tool. My full range pipes sounded amazing, but I really just wanted to keep building
Here's a picture of my pipes under construction...
I've read somewhere that PVC pipes make good enclosures due to their shape and finish. In fact, one of the best speakers in the world have an egg-shape plastic enclosure, and they're well regarded. It's something to do with the way waves bounce inside the pipe.
Anyway, I find the process of building them dead easy. Definitely worth trying.
Nice. ABS pipe works well too. You might want to take a look at the Linkwitz Pluto and LX-mini designs for additional ideas. The Pluto includes equalization to get the most from the driver, including a notch filter at the pipe resonant frequency.
PLUTO-2.1 omni-directional loudspeaker
PLUTO-2.1 omni-directional loudspeaker
You're right, they're very sensible regarding the placement and the room. When you have a driver that's big enough (like a subwoofer), it doesn't really matter if the room sounds bad. The bass will probably sound like crap, but you'll still have plenty of it.
I also have some BRs with 6.5 inch woofers and they struggle with the room too.
I also have some BRs with 6.5 inch woofers and they struggle with the room too.
I have the pictures in post #2 and here is one of the woofer laying on the baffle on top of one of the tall pipes. I will start a build thread in for my speakers in the multi-way section in the next few days.
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I cut the rings out of MDF with a router using a Jasper Circle jig. If you're going to build speakers you have to have a good circle jig. The model 240 makes circles from 1 inch to 18 3/16 inches in 1/16 inch increments. You'll want the polycarbonate version. I used epoxy to glue the rings to the PVC. They are never coming off. I'll show it all in my build thread.
The RS225-8 is actually the perfect size for 8 inch schedule 40 PVC pipe so the rings are just a nice solid mount for the drivers. Here's a picture showing the speaker laying on the pipe over a piece of foam. I actually used the speakers this way while I designed and tested the cross-over. I was surprised by the fantastic sound they produced without being secured to anything!
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I never had one. Nor a mic
I like the speed and accuracy of the circle jig. I used a jigsaw at first but spent too much time cleaning up imperfections....
Yeah, a Jasper jig will yield better results than a saw for most speaker building circle cutting needs. I always find it a pain to get the pin thing in the right hole though.
Anyhow, cool PVC pipe speakers! Nice to see someone actually place the driver at 1/3L with a T fitting for the 'mid' pipes. Mostly we just see end loaded TL pipes. I can understand end loading the big ones, as the increase in gain is likely a worthwhile tradeoff, and the exits are distant enough that there probably aren't going to be any huge nulls - compared to room effects anyway.
The most challenging thing for me was figuring out where to put the pin to cut a disk of a specific size. The jig is designed to cut holes, so if for example you want an 8" disc rather than an 8" hole you have to add 9/16" to the end state measurement so the jig cuts the disk to that desired size.
Thanks! I have to credit Martin King and his spreadsheets for the design. The speakers came out sounding great without second guessing. PVC did allow me to play around with the lengths and I found myself going back to the calculated lengths every time. They just sounded best that way...
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