Hi,
I wouldn't think so.
The distance from the cavity opening to the chamber backwall still defines the dominant resonance frequency.
jauu
Calvin
I wouldn't think so.
The distance from the cavity opening to the chamber backwall still defines the dominant resonance frequency.
jauu
Calvin
Ah, thanks. Don't know why I was thinking dominant resonance was between the top and bottom walls.
A pair of dual driver ri-poles has been on my to-do list for many years. Think I could get decent low frequency extention with 4x 10" drivers (0.43 Qts, 43Hz Fs, 10mm Xmax)? I don't need a lot of spl and have plenty of EQ and power.
A pair of dual driver ri-poles has been on my to-do list for many years. Think I could get decent low frequency extention with 4x 10" drivers (0.43 Qts, 43Hz Fs, 10mm Xmax)? I don't need a lot of spl and have plenty of EQ and power.
You can expect output to about 33hz which I consider deep enough for 99% of recordings produced. It's all about the pure quality bass a Ripole produces and less about the last few herz.
I finally finished my build, was on vacation in the mean time. I included some build pictures and one where the finished subs can be seen with my setup. While i remember that Jazzman once called the build of a RiPol "easy" i had quite some challenges with it. First of all the 7cm radius cutouts for the magnets were too small for the router i had and therefore needed some help from a local carpenter to get them done. In the end i still had to use a rasp to shave off a bit conically to get a flush seal. Due to the length of my design i also had to include another metal bracing at the back to get the two chambers to seal flush. Otherwise my only real "problem" is that even though i sanded everything to 240 grit, the spray paint turned out more like 160 grit and i could not sand it the top layer without scratching it. Maybe i'll give them a different finish in the far future.
Now about how they sound with my Fosi ZA3 and the Yamaha V6A. First impression was underwhelming to be honest, with a distinct "where is the bass?" feeling. After adjusting the levels and listening to a few more songs this turned to excitement as the bass was actually there and very "clean" at that. Overall way less boomy than with my Versacube which is great as the rest of the songs in turn are more clear as well. While the configuration in my setup is certainly not perfect (maybe i'll try putting them under a coffee table in near field in the future) the bass does not come from a distinct place anymore and blends great with my speakers. Everything sounds full and balanced, my only nitpick is that they do not seem to pressurize the room (which to be fair Jazzman warned me about) so there is no tactile feedback to the bass.
Now about how they sound with my Fosi ZA3 and the Yamaha V6A. First impression was underwhelming to be honest, with a distinct "where is the bass?" feeling. After adjusting the levels and listening to a few more songs this turned to excitement as the bass was actually there and very "clean" at that. Overall way less boomy than with my Versacube which is great as the rest of the songs in turn are more clear as well. While the configuration in my setup is certainly not perfect (maybe i'll try putting them under a coffee table in near field in the future) the bass does not come from a distinct place anymore and blends great with my speakers. Everything sounds full and balanced, my only nitpick is that they do not seem to pressurize the room (which to be fair Jazzman warned me about) so there is no tactile feedback to the bass.
Attachments
Very nice looking setup. Funny, I considered making a whole console with integrated ripoles but abandoned the idea after playing with different placement possibilities in room - can't place it far enough from a wall.
Yeah i am sure my placement is also far from ideal, in the future i also plan to put them more near field but for now i really don't have any better options which is why i decided to integrate them. I'll just look at it like a "free upgrade" once i eventually place them more optimally
Nice idea ! But yes : you need some circa 40 to 60cm spacing free at the rear, so you can't put it against the wall...
That said : why not opt for a similar principle for a coffee table instead of a console ?
T
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A coffee table build would be cool but I would still want another sub, which would reintroduce the placement problem. And I do prefer my coffee tables a bit more "airy" aesthetically 🙂
Nice job!……but as was expressed to you, the ‘where’s the bass’ thing is typically very disappointing. Most OB folks looking for sub bass just find a way to convince themselves after a while that it sounds good. Here’s the reality of the physics…..below 80hz or so in most spaces, the room is completely modal in its response and gain structure. The only way to get anything below 80z is to in fact excite as many modes as possible…..that is ALL that a subwoofer can do….there is no direct sound, no fundamental tones or notes…..it’s all just resonance.
If you look at it from a musicians point of view, the reality becomes quite obvious acoustically as the instruments that can play fundamental tones do this through chamber resonance…..like a speaker box does……large soundboard in a box piano, large enclosure strings like cello and bass, tuba, and of course drums……all simple resonant chamber devices.
From 250hz on down to 80hz, your ripole build in a stereo configuration would likely sound amazing……you’d have your clear and accurate midbass slam and direct tones with all of the intensity. From 80hz on down, you’ll need boxes or horns. And because the premiss is to excite as many modes as possible, one subwoofer is grossly ineffective and two isn’t any better and in many cases, actually worse. Three begins to improve things and gets the room fully excited but the real benefit is when you add the fourth…..the fourth creates enough of an additional pressure gradient with proper placement to smooth all of the modes delivering a very tactile, evenly resonant chamber that is fully coupled to the air.
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@mayhem13 ; I fully appreciate the overwhelming impact of the room below the Schroeder frequency, however I’m struggling with the concept that “there is no direct sound”. Assuming you have a sub that is capable of producing sub 80hz fundamentals then surely you will receive some direct sound at certain frequencies in any given location.
Was the problem with resonance with the curved build on the back side of it? I'm struggling to understand how resonance could form on the front side with that geometry.
No this is simply some kind of cavity resonance, the form of the cavity by itself has more or less importance.
T
With my ripole subwoofers I have got distortion problems at the low end.
I built two ripoles with 10x drivers a few years back. Thanks too all the information here. And of course Jazzman.
One has two peersless 831727 drivers. And the other some old Visaton. WF 26 bf.
Both driven by a dedicated crown amplifier.
If I try to get kind of flat response to a 20hz the subs create tremendous distortion from a 30hz down and they hit maximum excursion.
For reference, I encounter it with some classical music. Anna Lapwood with sangreal or Max Richter War Anthem for example. And I do like organ music...
How to get that flat response without the distortion.
Build a new one with just more power. Higher powered drivers like the Faital Pro 10rs430 and more muscle in the amplifier? Most of the recommended drivers here have similar specs to the ones I have.
Bigger drivers 12" or 15"? With or without more power. The crossover is around 50hz to the main OB speakers. So I am not afraid of resonance in the higher end.
Or schould I switch to a commercial subwoofer with low hz? The SVS sb 1000 pro, or the 2000 pro seem to do that very well. Will that do with the open baffle?
Regards
I built two ripoles with 10x drivers a few years back. Thanks too all the information here. And of course Jazzman.
One has two peersless 831727 drivers. And the other some old Visaton. WF 26 bf.
Both driven by a dedicated crown amplifier.
If I try to get kind of flat response to a 20hz the subs create tremendous distortion from a 30hz down and they hit maximum excursion.
For reference, I encounter it with some classical music. Anna Lapwood with sangreal or Max Richter War Anthem for example. And I do like organ music...
How to get that flat response without the distortion.
Build a new one with just more power. Higher powered drivers like the Faital Pro 10rs430 and more muscle in the amplifier? Most of the recommended drivers here have similar specs to the ones I have.
Bigger drivers 12" or 15"? With or without more power. The crossover is around 50hz to the main OB speakers. So I am not afraid of resonance in the higher end.
Or schould I switch to a commercial subwoofer with low hz? The SVS sb 1000 pro, or the 2000 pro seem to do that very well. Will that do with the open baffle?
Regards
@hjo : assuming you want to stay in the Ripole way, you would certainly increase the size of your Ripole unit, if it is doable, to afford higher loudness without issues...
I'll cite again one of my friends who went from a pair of Velodyne subwoofers to a pair of DIY Ripoles :
He went at home and listened carrefully to my - small in regard ! - Omega Ripole 2x12" :
He was amazed by the deep and clear tone, that unboxy floating infra-bass extension that provided my unit... Knowing him, I recommended him to go "larger, bigger, way much..." if he wanted to satisfy his tastes for loudness in any music genre (including Classic and EM).
After discussion, we decided to go for two 2x18" Ripoles design - I called them "D-Ripoles" thanks to their lateral shape, imagined by my friend :
They are cut at 60Hz / 24dB/Oct by an active crossover, and driven by (IIRC) LabGruppen 1kW amps each.
The 4 loudspeakers are these ones :
https://www.toutlehautparleur.com/haut-parleur-sb-audience-bianco-18sw450-8-ohm-18-pouce.html
My friend would not go back to his two - now sold - Velodyne subwoofers now...
IMHO and by our experience, in one word : if you want loudness with the benefits of the Ripole principle, you have to go "big" with large / high power handling / great Xmax speakers.
T
@tubelectron Thank you for your reply.
The 18" look good but are way to big unfortunately. I might squeze in one 15". But not two.
How does your omega perform in the low end?
What would be the big difference between conventional and ripole in music? I don't watch movies.
When I am in church with the big organ, I hear and feel the massive bass notes. Would the ripole be able to do that I wonder now. If possible at all in not to big livingroom.
The 18" look good but are way to big unfortunately. I might squeze in one 15". But not two.
How does your omega perform in the low end?
What would be the big difference between conventional and ripole in music? I don't watch movies.
When I am in church with the big organ, I hear and feel the massive bass notes. Would the ripole be able to do that I wonder now. If possible at all in not to big livingroom.
You need big otherwise the efficiëntie is to low, driving the speakers fast to it limits. Visaton has done one
with small speakers, but then also with 87dB watt it is quite low. knwing the petit organ I think.
with small speakers, but then also with 87dB watt it is quite low. knwing the petit organ I think.