Paul Voigt was a genius. I built a pair of Pipes about 3 years ago and love them. If you’re in doubt, build one with some cardboard an duct tape an throw a speaker in it. I think you will be amazed, an rushing to Home Depot for some plywood lol.
Indeed, that's an amazing thing with Voigt pipes. Even with crappy building materials one can get astonishing results. I do agree, everyone deserves to try them out! :)
Great job, Janos! I am an organ builder as well, so can attest to the fact that folding over a pipe makes little difference to its sound. We do this often to make pipes fit under low ceilings. It is called "mitering" and can employ some wild angles to fit in an organ chamber. Keep up the great work!
@@realworldaudio without much knowledge I made a folded voigt pipe (I later found out)...with arbitrary dimensions... But the sound after stuffing in a scientific manner is splendid.... It blew my mind... Voigt pipe concept is so robust I think it needs little attention to details... Of course details will improve the sound no doubt... Still ,any voigt pipe either folded or unfolded will sound better than most of the other speakers...
@@clearbrain That's quite my observation as well! There's just so much math about trying to predict the best placements, and yet my experience was that the best sounding pipes were all using sheer luck - I go with what looks and feels Right... the first folded pipe I designed for my brother, without any math for port size or driver placement turned out to be totally amazing. My first Voigt pipe also a similar strike - heard many afterwards, but none close. First and the last all in one ; ).
I found that in a bass-reflex box, you can suppress the up-down resonance well by putting the woofer and the port just outside major resonances (1/4, 1/3, 1/2, 2/3, 3/4th of the height). This leaves the back-front resonance, even if quite room dependent. Some say you should use box dimensions that do not correspond with our musical scales, others do (Janos has a video on this). When you don't, it may avoid agitation by played notes - but if they start resonating anyway it will sound very 'off'. I personally take the planned x-y-z internal distances and play the 3 corresponding notes on a piano, just to hear what those resonances sound like. If the chord sounds good, I'll continue with those 3 dimensions :)
Yes! I also use the 3 dimensions and take them as chords, and listen to the chord played on a piano or guitar on how it sounds... if I'm satisfied, it;s a go. ; I also did something weird: I tuned the VOL for the A422.5 that's common in baroque music... as baroque is my favorite music. (Instead of the A440 scale of contemporary music.) The tuning still works, as the relationship of the 3 notes is the same - just it gives baroque the extra edge... ; ). (Actually, in the Baroque period they used everything from about 398Hz-430Hz, yet Handel and Bach used 422.5 the most, hence my choice of the tuning frequency... )
Awesome video! Having just built a pair for some random full range drivers that came from some junk bookshelf speakers your explanation of the theory tied it all together. The speakers came alive in a larger room and with a little mass loading, now I feel I should do a proper build with decent wood not particle board countertops and some decent drivers! Subscribed!
This video was so endlessly helpful. Many, many thanks for this vid. As I’m trying to figure out the best type of cabinet to put my tweeters and drivers in, this video has given me some great ideas for possible cabinet designs. Thank you very much, Janos.
go for this _| shaped internal baffle design, with a slight till up at the top, the driver is sitting in the middle the cabinet. make sure you keep your dimensions of the internal baffle nearly the same to the backside of the internal baffle volume and back of the speaker only 3% more volume. you want to keep control of the driver free air movement, the pot opening can be quite large, you will achieve 8 order bass reflex. what size and drivers you got what sort of tweeter driver
@@hoobsgroove Hey Hoobs. Thanks very much for the info. Any ideas are very helpful. The drivers and tweeters I’m using are from 1959. They’re by Pioneer. The driver is an alnico 8” and the tweeter is a compression driver horn. They’re already in a cabinet, but I think I can design a much better one. Here’s a vid I found of the speakers. This isn’t my vid, nor would I have chosen the music. lol It shows the inside of the speakers though ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-hDBa3hNaPZU.html
Brilliant explanation, thank you. The single full range driver / horn & voight/lowther fanboys seem, not totally but highly correlated with the tube and dare I say no feedback SET extremists, and while there are some deep truths in there (class A is good) there seems also a LOT if snake oil smoke and myth (this or that resistor or capacitor will change your life, use only left handed solder on the left channel etc. Height gives you lowest 2/7th wave, angle hence volume to hit Vas .. simple !
Thanks for an amazing video! So much technical information squashed into a short video. I feel I now know the basics of Voigt design speakers like the new Sibelius by Pearl Acoustics. I don’t yet understand why it’s so expensive, though, since it sounds pretty simple to design and manufacture from your talk. I also feel I’ve learnt from you that Voigt pipe designs and transmission line designs are actually a totally different concept even though they have superficial labyrinth similarities. It seems that the a Voigt pipe aims to create a wide range of frequencies whereas the transmission line aims at one resonant frequency. Do others agree (if you are still there a year later)?
Thanks for this update, I was thinking of trying to make some cabinets. Wanted your views on making this a live cabinet, I could try tone wood and make them much like a musical instrument, if so any views on thickness, thought to follow your idea of support frame for the speaker, mounting and then add the panels allowing experimentation with the mount, interface, etc. Your thought and ideas much appreciated as you are much further down the road.
Hi Paul, for tone wood cabinet the general idea on thickness is: the better the wood, the thinner it can get. The thickest would be a 3/4in (18-20mm), and the thinnest 1/4in (5-6mm). The best recommendation for imparting the least personality on the sound is spruce, but that gets impossibly expensive for a large cabinet size. You can try any tone wood, as long as high quality and aged to some degree. All will work extremely well, and different wood gives different personality - just pick the wood you like the most. Generally, for thickness 1/2in is the practical thickness for a large panels, thinner high quality wood is very hard to come by. Good luck! ; Janos
I thought about this today. If a voigt pipe that is 2 meters tall can support a certain frequency, then it stands to reason that if I have 2 meters of space in my room, then my room should support the wave as well... Unless I am misunderstanding something about the quarter wave.
Hi Dan, the 2m in the pipe is not the full audible wave, just a quarter of it. It will give birth to the audible wave: the quarter wave has to extend to a full wave in the room to become perceptible and gain the room boost, which is the most important consideration for the low end of bass response in a listening room. The room should be 8m to hold the full wave - if shorter, the full wave cannot form. We can imagine this as an exercise rope: we are holding the rope at 1/4 of the length to generate the force that gets the whole rope moving. It's not the entire rope coiled up in the pipe, only 1/4 of it... ; So, whatever the limit of the room, the pipe can go only that low, as that's the rope/air it can tug. The rest of its potential gets unfulfilled, as there's not enough "rope" to get moving.
Thank you very much for the explanation. I would be very interested to see how open baffle compare to voigt pipe giving that Clayton and New Record Day praise the Caladan so much.
it is a port any opening is a port, and air doesn't leave the cabinet it excites the oxygen molecules in front of the port like a driver that produces the frequencies. not necessarily the size of room can determine low frequency response, it's more how many chambers can determine bass frequency, for instant if you had partition walls in your room you place the speaker in one corner and you sat at the other end of the corner well give the bass frequency enough length to reach you, because there's no cancellation in the frequencies. all rooms suffer from cancellation and this can be sorted out easily. when I said to you about bending pipe I meant at the top so it looks like a K from the side, instead of having 2m you could have it 1.5m tall and bend the other .5 metre at the top. the truncated is the best versions in can produce a much lower frequency as long as you put an internal vertical baffle from the port to the driver, it increasing the volume of the the internal volume pipe and the right pressure speed. this is the principal of PCM transmission line.
I have read opposing interpretations from loudspeaker designer professionals on what should be called a port. Some get very angry when a Voigt pipe opening is referred to as a port. Typically, a loudspeaker port is defined as a tuning device that opens a narrow bandwidth channel for energy exchange between cabinet internal volume and outside air. Here, the Voigt pipe opening does not behave in that fashion, if you do the modeling then if it behaved as a port then it would allow energy only between approx 200Hz-70Hz to be transmitted between Voigt pipe and the room. Which is not the case at all, the slot is open for a very wide band of frequencies because it is not operated as a bass reflex port.
In a helmnholtz design , the port tube ( call it an air plug ) inverts the phase of output . Hence the port output will be almost in phase with driver front radiation , albeit with a slight delay commensurate with length of travel from back radiation to port outlet . In voight pipe the port is functioning only as an outlet ( in the absence of air plug ) for back waves of driver and hence will not invert the phase favorably as desired to match with front radiation . So it appears that port output ( most of which is low frequency ) of voight pipe is almost 180 degrees out of phase . In logic , there should be a cancelation of low frequency . Paul Voight could not have been ignorant about this ! How is this physics addressed or the phase corrected ? Thanks in advance for your effort to explain .
I have to put this into perspective. The Voigt pipe was one of the very first cabinet designs ever, LONG before Thiele Small calculations became the standard, and any of the considerations you mentioned started to be addressed. It's kind of like saying how did the inventor of the brake handle the transition from ABS generation 5 to 6... the Voigt pipe cabinet is THE cabinet that was perhaps the first that was ever designed with acoustic puprose in mind, and not cosmetic as speakers before. However, the Voigt pipe addresses the issue you asked about very nicely: the mouth is at the floor level, and the mouth output arrives at you the same time as the first floor reflections do. So, in practice it works very well in an organic way.
@@realworldaudio the most helpful part was distinguishing between a bass reflex “air spring” and the 1/4wave being like a lever to excite bass waves in a big room…. It really helps to. Learn bAss will not be reproduced in a small room and So clearly understand now that the room impacts sound far more than joe average recognises
@@realworldaudio it was also extremely useful to learn that as long as the room has at least one direction long enough for deep bass waves that a voight pipe will have a chance to get that bass wave of excitation going (like a soccer crowd standing ovation being conducted by a crowd member in a big wave around the ground) I don’t fully understand it but since your explanation Of a little wrist waving a long arm I am Beginning to get it
@@realworldaudio while I am taking up your precious time I am very interested in BIB 1/2 wave speakers (terry caine) Where the “speaker opening” (there is no top plate) points to the ceiling and there is an internal baffle looking to me a lot like an upside down folded voight pipe These BIB speakers are often 2.1 metres tall and the transmission line would be double their 2.1m height…
This might be a silly question, how is the Z axis built? We're only seeing X and Y. Its the final box flat sided or more like a tetrahedron? And is the front baffle a flat plane or bombé, in order to deal with edge diffraction ?
Hi Janos, could you expand on a Voigt pipe with Karlson resonator (Not the Karlson box, though separately that would also be cool). Also damping reduces the air speed in a quarter wave pipe, would you dampen a Voigt pipe, and how?
Nice presentation! Two question please. (1) How the properties of the pipe are changed if using a straight, not tapered, pipe of the same length and internal volume, and also assuming the same locations of the driver and opening? (2) Formally, Voigt pipe is different from the tapered TL by the opening location. What will happen if on makes the opening on the narrow end instead of the wider one of a given pipe? Thanks.
Hello Igor, 1., if not tapered then you get all the box resonances and are back to a boxy cabinet sound. The box is resonating at 3 peak frequencies instead of being a frequency-neutral device. 2., as the air exits through the high pressure region it will behave more like a bass reflex cabinet with an unusual shape.
Hi, very interesting, I used to work for walkers the organ building company back in the UK back in the late 80s early 90s and I was a specialist wood machinist and I used to make wooden pipes some bar restoration but some are new, Some were tapered and some are parallel but with unequal sides and back, And back then I made some of the biggest organ pipes in the world, Give you some idea I colleague of mine crawled down inside and stuck his feet out the bottom of the pipe and I sat in the top it was quite a funny experience I can’t member exact length of the pipe but I think it was somewhere at 16 m 18 m in length, 60cm x 80cm Dm . it was then cut to length for voicing, In the early 80s I built myself a pair of transmission line loudspeaker cabinets internal line is around about 12 1/2 to 13 foot in length, 12” X 14” , 8” driver, and tweeter, made bye peerless, but 3 weeks ago I had to change them as one of the drivers burnt out, so now I have replaced them with Seas drivers, the original tweeter was oblong shape, so I made a square plug to fill the original hole, I put it on my wood lathe and turned the centre out to accommodate around tweeter unit, The plans I got out of old hi-fi magazine from the 70s , they Sounded amazing then, but now they’ve come alive and sound even better still specially the deep bass. I do not have equipment To test them apart from playing music and everything I seem to play sounds completely different Sounds amazing. Phil from the moulin France.
can't help wondering if the ancient Egyptians were trying to build super big speakers, when they built the pyramids? Pity they couldn't buy the drivers for another 5000-years, but...WOW, if only they had!!!
Wow, I just tried to imagine placing a 16in Altec into the pyramid capstone, and firing it down... huge party!!!! ;) Wish they made pyramids like that... if we could have sent James B Lansing back in time. (James B. Kheops?!)
@@realworldaudio haaaa...that's why I commented, to stimulate your obvious Creativity! :-) Brainstorming SHOULD begin with Laffter! However, I envisioned a pyramid shell, with a cross-corner dividing interior "wall". From point-to-base, at the corners. In plan, an intersecting cross. One driver would be mounted on each of the upward-angled sides, allowing for broad dispersion (take that Dr. Bose! :-) Here's the thing, I'm an old ECOhome Designer/Builder who's built many speakers (remember SpeakerLab in Seattle, kids?), and some "nutty" clients have wanted "pyramid" homes, which is REALLY "nutty"(!!), and I refused. Still, the pseudo-science of "pyramid-power" stated all sorts of "magical" attributes to pyramids. Who knows, readers, maybe such a speaker as I've described may be the "answer"!!?? :-) If anyone can, it'll be...YOU ! post a video! buona fortuna! by the way, the GREATEST Creations have begun by using paper & pencil (or, scratched on mud tablets))), and I'm so very glad you use simple tools, too! Psssttt...I've got 9-12" Peavey's you can use for your experiments, no charge!
How about using something which is always way too happy at 20hz but is the best woofer in the world too? I'm talking about purifi 10" & then using tiny mid & tweeter like the bliesma 3" dome mid & 1" Tweeter placed very close to the woofer? Won't that work too? Instead of just a single full range driver?
Hi, I have some 3 inch Full range drivers. Can I make a 1 meter tall Voigt and have a Full 80HZ to 40Hz extension? Fs is arround 110HZ. Was thinking about a port loaded enclousure but I liked this very much! Also, do walls need dampening? Thks
It might work, although Voigt pipe do not like short lengths, I'd recommend 1.4-1.5m. Also, if it does not work well as a Voigt pipe, you can still transform it into a slot ported bass reflex - just close down the mouth of the pipe to a slot port. Wall dampening would work with MDF cabinets, but a huge downgrade with natural wood. Overall, you don't need to dampen the Voigt cabinet as the triangle shape is a mechanical dampener - much better than any amorphous (dampening) material.
Very interesting information. Is it possible to have an extension down to 38 or 40 Hz with a single driver in a room with only 3 meters depth and let's say, discounting the couch with the listener's position, with a distance between the ears and the front of the speakers of only 2.35 m? What kind of enclosure would that be and what specification should the driver have? I have been looking at the ones made by EMS from France. Thanks in advance.
Hi Janos… I am planning to buy a pair of Teresonic ingenium silver speakers but I have to buy them without listening to them. Your explanation was very useful to understand how they work. Do you listened these speakers?. I would appreciate your opinion . Thank in advance!
Yes, the folded pipes (TQWP) are like that. You can place the driver basically anywhere, it will be a little different, and there's a lot of math to figure out which is the most optimal. Yet, the most optimal will be the one that matches your room and your amplifier the best, and that for all practical purposes can only be found out by trial and error. Look up TQWP, there's tremendous amount of resource on it. ; )
Yes, they do! However, they do not do that much damage as the cabinet in not pressurized (as sealed or BR cabinets are), plus the triangular sides prevent that frequency from bleeding over to other resonance modes and planes.
Any tweaking to insert another calculated magnet in the driver to increase flux with proper calculations to increase flux in high efficiency drivers with less Resla or gauss like coral
Hi Janos,..it,s me again. I Have Build a Little Model 1:10. Now I,m thinking about it, can I put the Port downfiring with 5 cm Distance to the Ground and I will use only 4 mm Plywood for Cabinet. What do you think about it,…is it wrong or possible?
Hi Roberto, I think it's a good idea. I would recommend thicker plywood to the sides, keep the thin only for back and front. Also, use 4mm ply only it it is super high quality. If not, then I really recommend 10mm or thicker. I have not seen yet plywood thinner than 6mm that would be of sufficient high quality. You might get lucky though if you have very good lumber in your area. Good luck!
Did you know Hans Kortenbach (RIP) from Musical Affairs? He experimented with 4 mm Tonewood and he said that was the biggest Jump to Natural Sound. He builded his Cabinets like a Musik Instrument too without any damping Materials,…but with Wood Rips to elimate to much resonances. Stability is Not the Problem,….Wings from Model Aeroplanes are builded with very Light Balza Wood.
OK, I built Voight pipes which are about 74 inches tall and the floor of the cab is 10 inches deep. I calculated my cubic foot volume as 1.82 cubic feet (roughly). My current driver is a Pioneer B20FU20-51FW8. I want to replace these as the surrounds are falling apart and these drivers were very cheap (not worth repairing). Their specs are VAS 1.75 Cu Ft, Freq Response 36-17000hz, FS 53hz, SPL 90db. I don't know if these were a good match or not. Since you've built these for so many years, is there a Fostex or other replacement driver you'd recommend for my Voight pipe? I use them with a low power tube amp that prefers efficient drivers. Any help would be greatly appreciated. Thanks.
After reviewing the Fostex 8 inch drivers I'm leaning to the FE208EZ. Vas 2.12 cubic feet, Fs 42hz, SPL 97db. Anyone who can point me in the right direction, please do so! Thanks.
Hi Joseph, sad to hear that the surrounds are falling apart. Sadly, that goes with old age of the driver inevitably at one point... that Pioneer was a good match for the cabinet. The FE208EZ will work well, also, the FE206NV will be a very good match too. Good luck, cheers, Janos
@@realworldaudio Thank you, Janos. I installed the new drivers this morning and I'm impressed. A lot more detail and clarity, and since they're more efficient, a lot more volume. I'm impressed with the bass produced by the enclosure.
Hi Joseph, thank you for sharing your experience, I'm glad it works out so well! Which driver did you go for, the FE208EZ or the FE206NV? Cheers, Janos
What are your thoughts on tuning the box to a half wavelength of the drivers fs? Are there any advantages to creating such a large enclosure? See bigger is better (bib) speakers.
That's super low tuning. The disadvantages are that the longer the box / tube / pipe, the longer the latency for the wave that exits the "port", so the timing will be more and more off. (The Voigt pipe can pull it off because the port in at the floor height, and the bass from the port arrives at the same time as the first bass reflection off the floor, which is very natural.) Also, if you go that low, to take real advantage you need a room that has the length to support the full wave. For half the Fs the room size is so long / big that it is really pushing the drivers Xmax at the low frequencies to produce useful volumes. So, essentially, the range where they can be enjoyed fully is in an extremely narrow SPL zone. (Any less and you can't experience the 20Hz, any more and it breaks up.) I find that the appox 2m pipe length is the goldilocks zone - go for less and loose low bass, more, and we are losing the headroom and going so high into excursion that the cone is driven to distort in the highs all the time.
Similar surface area as the speaker cone is the starting point. It can be bigger if the room allows - the exact size will depend on the room, trial and error. Also, if Qts of driver is higher (around 0.4) then bigger will work better in most rooms, lowish Qts (0.25 or so) will need smaller, but depending on the room a bigger opening can work as well, but less success as a higher Qts driver.
@@realworldaudio Thanks! Are you tuning the port to the low frequency cutoff of the cabinet? Like for a pipe that is 30hz tall do I tune the port to 30hz?
I assume with my basic understanding, this only works well with single driver, like your Cube Audio? How is timing behind the speaker, can they be close to the wall? So this speaker designs/single drivers are hard to drive, any AMP combination to recommend?
no it can be used for multiple drivers like PCM and it does work best close to the wall for more bass enforcement. if you make an offset tweeter MTM, you word want a vertical internal baffle opened at both ends top and bottom with both woofers having their own chamber like this [=| ], and in the centre rectangle port at the back. the vertical baffle behind drivers can be tilted at the small angle like they have their own voigt pipes each driver, joining a biger chamber. this is the best for clarity and for extended low frequencies you should be able to get down to 17.2Hz with authority in a medium to large room just use two Markaudio 4 inch drivers and a for ease of application 1" scanspeak or seas softdome tweeter crossover about 4.7kHz 3 order
Hi Gerald, yes, it can be used with multiple drivers as well, and there are a lot of examples when people use a combo of mid/woofer and a tweeter. Overall though, due to lack of cabinet resonances, people find that single drivers are just vastly superior in midrange reproduction, and multi driver only makes sense when listening to badly recorded music (that requires bass boost), or one wants to listen to at excessive volumes where one driver is not sufficient. Proximity to wall: will make them sound like regular speakers... so yes, it works, but without optimal placement we are missing most of the advantages that these cabinets offer.
Hello Nilo, you can use it either in mono (one speaker) or stereo (a pair of speakers). The Voigt pipe was the creation of Paul Voigt in early 1930s, and since there were made about a hundred or more variations on it. I found that keeping closer to the original has the most potential. My Voigt pipe is kept close to the original design.
Wouldn’t a passive radiator help increase the free air volume in the truncated pipe a,lowing greater frequency extension in a smaller cabinet. From what I can see the draw back for most users will be the size/height of these cabinets. (Just a casual observation, you did say this tutorial is for IDIOTS😀)
Hi Eddie, it's definitively worth to play around with ideas, so thumbs up! With careful selection of a passive radiator indeed we could incease the apparent volume. Sadly, much of the energy would be lost from the transmission line (the pipe) through the passive radiator, and the quarter wave output at the Voigt port would be too low in volume to play a significant role. We want the air column to resonate, and more volume means more air can resonate, creating a stronger wave that can couple to the room better. This is the sad thing about audio, all the compromises come when we try to make the loudspeaker size smaller.... that's what 95% of all loudspeaker development was and is about, how to do damage control with small cabinets.
Got it. Just that I thought I was seeing PR in some newer deigns which reminded me of truncated Vought pipes so I imagined that’s what they were trying to achieve.
@@EddyTeetree I think their main purpose is to cut down the cabinet resonances. Every cabinet type benefits from the Voigt pipe / truncated Voigt pipe shape, due to lack of parasitic cabinet resonances. ; ) We have been seeing almost exclusively the boxes everywhere as they are the easiest, fastest, smallest and cheapest to build : (
Are you assuming your viewers are dummies because they don't know the physics of voight pipe? You should rename your video Voight pipe physics explained.
Hello Michael, I must assume that you are not familiar with the world-know For Dummies textbook series. I named the video after the popular textbook series, which have been running already for 20 plus years world-wide. It is not an insult on people's intelligence, quite contrary. The For Dummies series are concise textbooks to guide through the readers from the basics to working knowledge, and this video follows that approach to the subject, hence the word choice.I hope my answer helped to re-frame the title's word selection. Kind Regards, Janos