You can stick damping from outside or inside the cabinet, both will work.
Stuffing the entire pipe wont solve the problem if vibration of steel is source of ringing.
You can put some behind driver, but not below.
Stuffing below driver will eat up efficiency and bass.
But feel free to experiment.
Stuffing the entire pipe wont solve the problem if vibration of steel is source of ringing.
You can put some behind driver, but not below.
Stuffing below driver will eat up efficiency and bass.
But feel free to experiment.
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Sorry to hear it's resonating, but I'm not surprised. It's certainly worth experimenting with damping stuck to the outside, I wouldn't think it makes much if any difference it being external? It may be worth soft coupling the driver too, most of the energy exciting the panels will be mechanically coupled.
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Of course.
You're conflating panel resonance with acoustic resonance. Panel resonance = not good, but with steel panels, it should be high frequency & high Q, so very easy to kill with small amounts of panel damping e.g. bitumen etc., carefully placed at the main resonant modes. That's one of the advantages of using metal: it doesn't take much to kill it, unlike, say, MDF, which in reasonable thicknesses will usually require significantly more.
Stuffing (or acoustic lagging / lining) is used for a completely different purpose. The object of these boxes is to generate and use standing waves to extend the low frequency response. Since these also come with unwanted harmonic modes, as has been explained previously, stuffing (or lagging) is used to attenuate those unwanted pipe harmonic resonances, while aiming to preserve the primary (fundamental) low frequency resonant mode.
Much of the time, it's claimed you should simply stuff the region above the driver, which isn't particularly accurate. If you can access it, I would line the back and one sidewall with damping material like bonded acoustic fibreglass or an equivalent wool felt from top to bottom & adjust from there as desired. That will have very little effect on panel resonance, but it will help attenuate unwanted harmonic modes. If you want to stuff it, a very low-density of hollow-fibre material throughout will have more or less the same effect, or you can use a slightly higher density of stuffing from the top to about 1ft below the driver. Try to avoid stuffing in immediate proximity to the drive unit though.
I'll try the visaton bg-20 then. I did have a speaker with a whizzer cone ages ago, sounded amazing, though the little blip they make when they change from the big speaker to the whizzer was a bit annoying. in this case though i'll take the advice. I've started the process to get internet banking working again, may take around 2 weeks to complete.
I found a dual magnetic beacon today and moved it all over the cabinet to see would it make any difference. it wasn't conclusive, any change might have been psychosomatic.
I cut out two steel panels for the next composite voigt pipe. I will only make one cabinet initially to test out the effect.
I found a dual magnetic beacon today and moved it all over the cabinet to see would it make any difference. it wasn't conclusive, any change might have been psychosomatic.
I cut out two steel panels for the next composite voigt pipe. I will only make one cabinet initially to test out the effect.
Interesting, but I think i'll pass until my confidence improves. it wouldn't take much of a shaky hand to crumple the whizzer cone. But like i've often seen written about foolhardy mods, if they were that good of an idea the factory would have carried them out.
I should have internet banking working again in a week or so. no luck with the debit card but the speaker site stated they take bank drafts.
I drilled about 25 holes today for the flanges where the steel half of the composite voigt pipe bolts to the wooden half. It would be difficult to drill them after they are welded in place, not enough area to stick the mag drill to.
I have ran out of supplies, will need to stock up on plywood and cutting disks before i can proceed. not sure if i can get low void plywood but hopefully it will work without.
I have been listening to my voigt pipes for a long time each day since i set up both. the ringing doesn't occur on low power. I really like them, although they are flawed with a low volume on the lowest of low frequency bass, and a stepped driver plate. I wonder what improvement i will see with the next build, given a better speaker and construction. There's a chance it will still ring but if it does i'll go all wood next time, and should be able to reuse the wood used in the composite build.
I should have internet banking working again in a week or so. no luck with the debit card but the speaker site stated they take bank drafts.
I drilled about 25 holes today for the flanges where the steel half of the composite voigt pipe bolts to the wooden half. It would be difficult to drill them after they are welded in place, not enough area to stick the mag drill to.
I have ran out of supplies, will need to stock up on plywood and cutting disks before i can proceed. not sure if i can get low void plywood but hopefully it will work without.
I have been listening to my voigt pipes for a long time each day since i set up both. the ringing doesn't occur on low power. I really like them, although they are flawed with a low volume on the lowest of low frequency bass, and a stepped driver plate. I wonder what improvement i will see with the next build, given a better speaker and construction. There's a chance it will still ring but if it does i'll go all wood next time, and should be able to reuse the wood used in the composite build.
They're not that delicate -all you're doing is putting a bit of damping material (either open-cell foam or some teased out dacron) between the whizzer and the main cone. It ain't that difficult!
Which is predicated on the assumption that they are 'foolhardy' in the first place -which hardly applies to an entirely reversible bit of damping. Regarding modifications in general, it depends exactly what is being done. Some can be misguided. Some very far from it. Manufacturers do not typically optimise every single aspect of their products, because it is not economically viable or physically practical for them to do so, even if it might seem so to a DIYer who has no constraints on time, and who doesn't need to design and set up extra sets of jigs and tools in the production line, as would be the case for many of the more involved changes (various forms of targeted damping for e.g.).
It rained all day so i spent the day completing the composite voigt pipe. after a false start where i realised the new pipe was exciting the old pipe passively i removed it from the room. i stole an 8 inch 8 ohm driver from one of my monitors to install in the pipe.
The pipe seems to be acoustically dead. when i strike at the base like i did with the other, it doesn't continue to ring at all, just gives one ping and that's it. i wasn't able to put my ear up to the speaker port as it was installed.
I'm shocked how terrible the speaker is, no highs on it, when moving the balance between left and right speaker. will work much better with a full range i expect. seems the damaged car audio driver i was using was better than expected, or the speaker manufacturer selected one without highs in order so that it would not interfere with the tweeter.
In theory this should be better than a cabinet with a lot of material inside as the internal geometry is close to ideal. the only compromise i made was a slightly smaller bottom port due to an extra bracket to bolt wood to steel.
I ran into difficulty with a gap between the two wooden surfaces. it is vibrating with strong bass. I'll have to buy a glue of some kind. I'm thinking of heating up hot glue in a saucepan and pouring it along the join. the gap was caused by the mating surfaces not being absolutely flush due to the steel warping while welding. wood is not my preferred material for working with.
I can crank the wattage up so high i fear the speaker will blow and it stays clear. i pause the audio and it's instantly dead silent, the old pipe would ring for a few seconds.
In some percussive music i can hear the steel tone the cabinet imparts. i'm fine with it so long as it doesn't ring. i guess if i had a wooden pipe there would be a wooden tone (which there is actually, but not noticeable)
I will make the other pipe in a mirror image. all in all i think the project was a success.
I will throw my old pipes up for sale.
The pipe seems to be acoustically dead. when i strike at the base like i did with the other, it doesn't continue to ring at all, just gives one ping and that's it. i wasn't able to put my ear up to the speaker port as it was installed.
I'm shocked how terrible the speaker is, no highs on it, when moving the balance between left and right speaker. will work much better with a full range i expect. seems the damaged car audio driver i was using was better than expected, or the speaker manufacturer selected one without highs in order so that it would not interfere with the tweeter.
In theory this should be better than a cabinet with a lot of material inside as the internal geometry is close to ideal. the only compromise i made was a slightly smaller bottom port due to an extra bracket to bolt wood to steel.
I ran into difficulty with a gap between the two wooden surfaces. it is vibrating with strong bass. I'll have to buy a glue of some kind. I'm thinking of heating up hot glue in a saucepan and pouring it along the join. the gap was caused by the mating surfaces not being absolutely flush due to the steel warping while welding. wood is not my preferred material for working with.
I can crank the wattage up so high i fear the speaker will blow and it stays clear. i pause the audio and it's instantly dead silent, the old pipe would ring for a few seconds.
In some percussive music i can hear the steel tone the cabinet imparts. i'm fine with it so long as it doesn't ring. i guess if i had a wooden pipe there would be a wooden tone (which there is actually, but not noticeable)
I will make the other pipe in a mirror image. all in all i think the project was a success.
I will throw my old pipes up for sale.
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It seems counterintuitive because you would expect steel to ring but it silences any oscillation instead due to the mismatch in resonant frequencies of the materials used. pretty cool idea, works on all frequencies and no downside apart from cost and aesthetics. I'd say you could do the same with the frugel horn by replacing the hidden internal plate with a steel one.
I put the damaged sony driver back in and got my highs/treble back in the music. i was worried that the cabinet had removed them but it was not so. i also siliconed all the joins and the bass leak has now gone.
I put the damaged sony driver back in and got my highs/treble back in the music. i was worried that the cabinet had removed them but it was not so. i also siliconed all the joins and the bass leak has now gone.
ping is the wrong word. I wasn't sure how to describe it but i showed a friend yesterday the difference between the ringing pipe and the composite and when i hit the latter on the metal in the same place as made the former ring he said it sounded like i was striking wood.
I ordered the visaton bg20, might be here in a week. i wasn't sure what to do with the old ringing pipes but the friend took a look at them and said he would use them as ramps to drain the oil from his car. i laughed but they're perfect for that purpose, very strong, and with a slender taper they won't catch on the bumper.
I ordered the visaton bg20, might be here in a week. i wasn't sure what to do with the old ringing pipes but the friend took a look at them and said he would use them as ramps to drain the oil from his car. i laughed but they're perfect for that purpose, very strong, and with a slender taper they won't catch on the bumper.
I completed the steelwork of the second matching speaker today. made a slip up when i didn't mirror the design, had a brain fart. shouldn't make much difference to the audio though. Don't want to assemble the wooden section without the new drivers to save silicone and labour.
I realised that i can compensate for the warpage of the steel which occured again by overlapping the timber butt joint in the other direction, so i shouldn't have the same issue of bass leaks.
I realised that i can compensate for the warpage of the steel which occured again by overlapping the timber butt joint in the other direction, so i shouldn't have the same issue of bass leaks.
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Cut the bottom plates off, hang a steel ball speaker cutout level and make an 'A frame' to hang the set from. Wind (or hand) chime yard art deco - 200 euros!
Welders make all kind of crazy stuff for yard decorations over here. Works for some people!
"edit" - Ah, I see you've already found a good use. Oil change ramps for those low cars!
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I have a question, wouldn't it be easier to avoid unwanted resonances in a pipe by using an odd number of sides. For instance if i was to make a 3 sided voigt pipe out of steel, what would the dimensions be. I understand if nobody wants to build something like this out of wood due to the difficult angles required but that would not be an issue with steel, since they are all butt welds.
I find the non resonant steel makes the music come alive somehow.
I suspect an entirely steel cabinet has the potential to be superior to a wood type, because of a greater ability to transmit audio waves.
I have a little metal left over and could build a triangular mini pipe with a 3-4 inch driver to test the theory out.
Has anyone done this before, i have seen some corner cabinets on youtube that sound brilliant.
I find the non resonant steel makes the music come alive somehow.
I suspect an entirely steel cabinet has the potential to be superior to a wood type, because of a greater ability to transmit audio waves.
I have a little metal left over and could build a triangular mini pipe with a 3-4 inch driver to test the theory out.
Has anyone done this before, i have seen some corner cabinets on youtube that sound brilliant.
I think i recall reading a site that mentioned a 3 sided pipe would be unfeasibly long, something like 20 feet to have the same acoustic properties as a voigt pipe.
I'd say a 5 sided metronome would be an easier build though.
eh never mind. i should have my speakers here in a few days and i'll be done building for a long time, especially given the cost of lumber.
I wouldn't mind blocking up most of the port on my voigt pipes for a mass load conversion and fitting the internal baffle. I'd have to purchase a hole saw though.
I'd say a 5 sided metronome would be an easier build though.
eh never mind. i should have my speakers here in a few days and i'll be done building for a long time, especially given the cost of lumber.
I wouldn't mind blocking up most of the port on my voigt pipes for a mass load conversion and fitting the internal baffle. I'd have to purchase a hole saw though.