I'm back in Oz now and will be moving into my new home in about two weeks! It's been a long wait, but we've had a lot of fun being homeless.
The OB bass system I was playing with used a total of four 32W/4878T00 woofers in two W baffles, minimum size that would fit. Placed directly behind the listening seat and crossed at 80Hz the bass could not be localized and was able to reach rather entertaining levels if necessary. Walking outside the bass just disappeared, even though there was only a few mm of glass and about 2M between the OB subs and where I was standing.
It would work very well if the neighbours were just on the other side of a party wall.
For real subs I consider the implementation of far less importance than room and placement. 32 years ago I 've had a similar experience as Cowan above with a pair of sealed Audio Concepts Titan (or Saturn?) kits, the version using the AC12 12" Poly woofer in push-pull compound configuration. The -3dB point was 28 Hz.
Placement was a nightmare in my then apartment, until I put the subs side by side to the listening couch: fantastically low, easy and immersive bass.
Gary Galo, who reviewed these kits in Speaker Builder, came to a similar placement solution as optimum. Former member here Markus76 finally also came to this solution with the subs he used with his Gedlee Abbey main speakers. But move one meter (a foot if you like) and the magic is gone.
Placement was a nightmare in my then apartment, until I put the subs side by side to the listening couch: fantastically low, easy and immersive bass.
Gary Galo, who reviewed these kits in Speaker Builder, came to a similar placement solution as optimum. Former member here Markus76 finally also came to this solution with the subs he used with his Gedlee Abbey main speakers. But move one meter (a foot if you like) and the magic is gone.
I think it's better to install subwoofers in the ceiling. A program for quick position optimization would be useful.
Oh, I'm sure that you can find such products in UK ! We have this in France for years in Pinewood, Oakwood, Beechwood, Acaciawood, Teakwood, usually in 18mm planks, or thicker if it is for kitchen worktops. These are available in DIY supermarkets here (Castorama, Leroy-Merlin), and you certainly have the equivalent shops in UK...
Yes. Mr Axel Ridtahler is the inventor or the Ripole principle, but the Omega Ripole design idea is from me (AFAIK !). Have a look there :
https://guilhemamplification.jimdofree.com/hi-fi-other-projects/
T
Ditto to all you said. And the floor space can even be reduced to half.This is the only parameter where a Ripole Subwoofer would not be at his advantage : dB per Watt ratio. Otherwise, for all the others ratio mentioned in your post, @perrymarshall, the Ripole principle could compare very favorably to the other type of Subs.
---> Compact (mine below is 400x400x440mm, 2x12")
---> Lightweight
---> very low extension (15Hz for mine below)
---> unobtrusive but wide dispersion (effect of deep floating bass, when placed at the center of the main speakers)
---> no boxy tone or port resonance (there's non)
---> excellent damping and step / transient response (like a QTC=0.5 to 0.71 sealed enclosure)
View attachment 1249868
T
Mine are waiting for their open back coax to be finished.
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Before I build these I visited someone who successfully used them up to 200hz.
That is an additional plus as the midrange open baffle can be kept small.
Happy new Year
That is an additional plus as the midrange open baffle can be kept small.
Happy new Year
OK bigger than they appear in the photo but obviously still ok at 200hz. I suspect 15” would be borderline going that high.
I've tried Ripole 3 times with two different kind of woofers and always has some nasal sound and never sound right when compared with simple OB. All three times they were built to push 1/4 resonance as high as possible, resonance was damped by DSP, and LP filter was at least 1/2 octave below, but still.
Maybe there are some (unknown to me) other ingredients but was not successful for me.
Maybe there are some (unknown to me) other ingredients but was not successful for me.
A 3D volume can have as few as 4 sides.
An OB has a front and a back at a minimum.
Tubeelectrom’s lovely ripole and your U-Frame examples have many more.
dave
Yes, the tetrahedron has only four sides, and great strength to weight ratio.
More difficult to build than a 6 sided box.
A Klien bottle would make a great bass-reflex enclosure, informally it's a one-sided surface:
The heuristics of designing a Klein bottle bass-reflex will be quite the DIY challenge !
Art
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Ripoles are built and used by many audio enthusiasts and are used in very boutique systems and reviewed in Hifi magazines in Europe as very fast, neutral, tactile....
They work in most environments but not all.
There is a reason why you didn't succeed but it has nothing to do with the principal of Ripoles.
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Fascinating topic! Each speaker enclosure type has its unique set of advantages and limitations, and exploring the absolute limits of OB (Open Baffle), Reflex, Sealed, TL (Transmission Line), and Horn designs provides a rich ground for discussion.
In terms of OB, the open baffle design often delivers a more spacious soundstage and a natural, uncolored sound. However, it's essential to consider the challenge of controlling the backwater and addressing potential bass limitations.
In terms of OB, the open baffle design often delivers a more spacious soundstage and a natural, uncolored sound. However, it's essential to consider the challenge of controlling the backwater and addressing potential bass limitations.
Hard to say from afar. I built 10, 12, 18 inch variants but never encountered a nasal sound.
A set of solid measurements should reveal the problem. Nasal sound points to a problem that is at least an octave above the usual crossover frequency.
A set of solid measurements should reveal the problem. Nasal sound points to a problem that is at least an octave above the usual crossover frequency.
Heavy boxes are a game of diminishing returns, where you've got something like a 100:1 weight ratio between the magnet and cone (10g vs 1kg for instance). Most boxes won't be solid enough for ideal piston motion, but everywhere you look there's a noble attempt at multiplying that ratio by another 10x or 100x.
I've long questioned whether this is the right path, though. If dipoles and bass reflex ports are "allowed" then what's wrong with a purpose-designed box that vibrates like a cello (minus the strings) ? It's just a mechanical crossover, right? If you ever have a chance to get a closer look at the string family of musical instruments, note the craftsmanship with thin layers of curved hardwood and ultra-low mass.
I'm not saying it's a matter of installing a speaker inside an old guitar body. (Don't blame me if it sounds like crap). However, done right, it should be possible to control the amplitude and passband of panel vibrations, so they blend seamlessly with the driver.
99% of speaker drivers everywhere transmit anti-phase vibrations directly to the box via a circular ring with bolt holes pre-drilled. This seems like a necessary evil. Unless you want to go to great lengths to decouple the driver with a secondary frame of some sort, or horizontally opposed drivers. A few manufacturers make plastic frames, which may seem cheap, but this filters the passband of vibrations that get transmitted to the box.
My latest creation only weighs about 3-4kg. I haven't checked exactly, but it's a 14L box made with 10mm plywood and angled sides so the individual panels are quite small. The weak spot at the moment is the interface between the box and desk surfaces, where rattling may occur. But I plan on fixing this with a 'floating' base.