Hello Friends
I have a pair of SB Acoustics SB Audience BIANCO-18SW450 18" Subwoofer and Pair of Tang Band W8-1808. I have no knowledge of simulation software please can someone guide me what size OB can I make. I have a carpenter who can do all my cutting. Also have miniDSP 2x4HD I have no talent to make passive crossover can only buy the components and get it soldered but can't design a crossover.
My listen to variety of music Pop Rock I have not had great experience with money for nothing and Micheal Jackson songs on many speakers I heard.
I want to feel the punch in my chest and I sit approx 8 ft from the speakers. Oh on amp I have Hypex Ncore modules 100 watts and 500 watts stereo.
regrads
anand
I have a pair of SB Acoustics SB Audience BIANCO-18SW450 18" Subwoofer and Pair of Tang Band W8-1808. I have no knowledge of simulation software please can someone guide me what size OB can I make. I have a carpenter who can do all my cutting. Also have miniDSP 2x4HD I have no talent to make passive crossover can only buy the components and get it soldered but can't design a crossover.
My listen to variety of music Pop Rock I have not had great experience with money for nothing and Micheal Jackson songs on many speakers I heard.
I want to feel the punch in my chest and I sit approx 8 ft from the speakers. Oh on amp I have Hypex Ncore modules 100 watts and 500 watts stereo.
regrads
anand
You can try free sims yourself eg:
Edge/Basta for baffle design and the 6dB dipole crash and compensation/XO
Hornresp for OB sim for the SB 18" for SPLmax vs f to work out amp W and see if slam is possible
You can find all that info and more online. If you want a good outcome you will need to put the effort in yourself.
If you want the punch in the chest you cergainly should avoid an ob for the 18.
18" sealed, cut off around 200 hz with the upper you can OBs.
What you are looking for needs prezurisation in the 80 around 200 hz area and OB is known for better articulation of bass but not neceesarily the wow you are looking for.
However nothing should stop you to try the 18" in open conf, the nearer from the listener the better the effect as it is far from the front wall. However yourd dsp amp permit some bass lifting due to the OB loss in the lows with added EQ... but anyway I am not sure big distance between the OB and the listening spot is the best thing to do with OB bass load and for what your looking for. It's controversal in my basic understanding.
If you put it in a Uframe you may have resonance in the highs of the pass band that may dictate your cut off with the upper speaker to cross below the resonance.
It should be easy to experiment and make your first try...
18" sealed, cut off around 200 hz with the upper you can OBs.
What you are looking for needs prezurisation in the 80 around 200 hz area and OB is known for better articulation of bass but not neceesarily the wow you are looking for.
However nothing should stop you to try the 18" in open conf, the nearer from the listener the better the effect as it is far from the front wall. However yourd dsp amp permit some bass lifting due to the OB loss in the lows with added EQ... but anyway I am not sure big distance between the OB and the listening spot is the best thing to do with OB bass load and for what your looking for. It's controversal in my basic understanding.
If you put it in a Uframe you may have resonance in the highs of the pass band that may dictate your cut off with the upper speaker to cross below the resonance.
It should be easy to experiment and make your first try...
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http://www.tolvan.com/index.php?page=/edge/edge.php
Because of your requirement for "punch" (and that you have digital eq.) I would do a "SLOB" design:
https://www.firstwatt.com/pdf/art_slob.pdf
The "SLOB" basically adds-in some compression that provides a more tactile sensation = more "punch".
You would need to purchase an extra pair of 18SW450 to do this properly, but this would help-out with spl vs power compression (meaning that after eq. you could play louder than with a single 18SW450 per loudspeaker.
For the Baffle and Fullrange driver placement on-baffle - try modeling a 700mm [x] by 1000mm [y] baffle in the Edge with a 220mm driver centered horizontally at just under .8m and the virtual "mic." centered on the Fullrange driver with a set distance of 2m; remember to check the box on "Open Baffle". This should provide a useful "bump" from about 140 Hz to 600 Hz (that can be "eq'ed flat) - with that added "bump"/spl providing a bit lower non-linear distortion in that range than normal.
Target a crossover freq. near 150 Hz. (..and the digital eq. should be able to cut-out the cavity resonance of the "SLOB" loading.)
Because of your requirement for "punch" (and that you have digital eq.) I would do a "SLOB" design:
https://www.firstwatt.com/pdf/art_slob.pdf
The "SLOB" basically adds-in some compression that provides a more tactile sensation = more "punch".
You would need to purchase an extra pair of 18SW450 to do this properly, but this would help-out with spl vs power compression (meaning that after eq. you could play louder than with a single 18SW450 per loudspeaker.
For the Baffle and Fullrange driver placement on-baffle - try modeling a 700mm [x] by 1000mm [y] baffle in the Edge with a 220mm driver centered horizontally at just under .8m and the virtual "mic." centered on the Fullrange driver with a set distance of 2m; remember to check the box on "Open Baffle". This should provide a useful "bump" from about 140 Hz to 600 Hz (that can be "eq'ed flat) - with that added "bump"/spl providing a bit lower non-linear distortion in that range than normal.
Target a crossover freq. near 150 Hz. (..and the digital eq. should be able to cut-out the cavity resonance of the "SLOB" loading.)
You can't simulate an open baffle because you can't model the random bouncing about and mixing of phase from the rear of the baffle in the intended room location. BTW, some of the bounces add and some subtract.
B.
B.
When you simulate an open baffle (really any baffle/box-shape) it's just there to get a decent idea of:
1. upper freq. response of driver relative to baffle size and placement (and usually just on-axis for something simple), and
2. some idea of presssure loss below the baffle's support and what will be needed to compensate (eq) anechoically - this in-turn provides some idea of what will be needed to compensate (eq) in-room and also what sort of increases in non-linear distortion and power compression there will be below the pressure-support region for the baffle.
In other words a base estimate to be "built upon".
In this instance the poster can (digital) eq. at his listening position so most of his problems are avoided.
1. upper freq. response of driver relative to baffle size and placement (and usually just on-axis for something simple), and
2. some idea of presssure loss below the baffle's support and what will be needed to compensate (eq) anechoically - this in-turn provides some idea of what will be needed to compensate (eq) in-room and also what sort of increases in non-linear distortion and power compression there will be below the pressure-support region for the baffle.
In other words a base estimate to be "built upon".
In this instance the poster can (digital) eq. at his listening position so most of his problems are avoided.
And a feet is 30 or 32 cm. It should be ok. OB needs a large room. But, chest pumpning is normally not OB territory
If that was true one can't simulate anything, since monopoles do cause reflections too. But I bet you know. I think Basta! can predict OB output on a given baffle BTW.
Although I am tempted to agree with you wholeheartedly, the simulation is worse for the dipoles because monopoles (whatever that is) modify or absorb their rear waves rather than shoot them out the back undoctored.
B.
Can you please post or link the evidence you have to support this assertion? It would be good to see the data of measurements of dipole vs sealed across a room. Thanks.
http://musicanddesign.speakerdesign.net/tech.html
http://musicanddesign.speakerdesign.net/Boundary_reflections.html
etc. lots of good info in the www
And I agree, "punch" in a largish room and dipole bass is like mission impossible. Only way is to sit in nearfield, but then you miss the dipole sound of mid/fullrange drivers....
http://musicanddesign.speakerdesign.net/Boundary_reflections.html
etc. lots of good info in the www
And I agree, "punch" in a largish room and dipole bass is like mission impossible. Only way is to sit in nearfield, but then you miss the dipole sound of mid/fullrange drivers....
A monopole radiates evenly at 4pi. Ideally it’s a pulsating sphere of which the diameter is small compared to the wavelengths involved. Given a certain bandwidth (low to medium frequencies) most ordinary speakers are acting as monopoles.
Hi, @Juhazi
Why you miss it in the medium and treble if too far from the front wall?
If the patern is an eigth, then you do not miss too much the side walls bouncing out of phase and only the big out of phase bounce from the front wall is missing.
So the main advantage of OB above 300 hz medium beginning should be the lack of box colration difraction and the box bouncing rear wave back on the rear of the cone that color somewhat cause very near the main front signal. I mean near in the cancelation timing behavior.
So what is missed in a close OB near the sweet spot as you can delay with dsp the front signal to time align them for the listener with the bass ?
Or does that mean if the mid treble is too far from the front wall you experienced too much of phase return...also called an echo ?
Why you miss it in the medium and treble if too far from the front wall?
If the patern is an eigth, then you do not miss too much the side walls bouncing out of phase and only the big out of phase bounce from the front wall is missing.
So the main advantage of OB above 300 hz medium beginning should be the lack of box colration difraction and the box bouncing rear wave back on the rear of the cone that color somewhat cause very near the main front signal. I mean near in the cancelation timing behavior.
So what is missed in a close OB near the sweet spot as you can delay with dsp the front signal to time align them for the listener with the bass ?
Or does that mean if the mid treble is too far from the front wall you experienced too much of phase return...also called an echo ?
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That is what is saying the theory, but I think it is truer from a listener perception point of view than a physical point of view of what really happen if we could finely measure it 360°.
Put your hand near a port of an aperiodic bass cabinet for instance and you will experience more pression than at the back of the enclosure and main should happen from a SLOB. The radiation patern sould not be exactly 360°. I'd like to see a mathcad patern or a very proper measurement to see what happen really. Anyway I beleive what we are listening is indeed in the bass a 360° sorta bass experience due to the waves length here in sort the wall of the room plus the cabinet act as a difusor with no real lag between the cabinet and the room due to the length of the waves than often exceed the room dimension, no ?
Main difference should be how are excited the room modes ? Sealed seems to create more presurisation, i.e. more low and high pressure windows because there is no out of phase cancelations of those nodes made by the back wave bouncing with open baffles.
If sealed and if slam punch needed, one should find a high pressure mode of the room in the 80/200 hz where it occurs, by experimenting distance between his chair and the front of the speaker.
Unluckilly this distance may be not the best in term of soundstaging when the best if often to place the listening spot inside the triangle nearer with the loudspeakes axis and not outside of the triangle ... ?
I really think it is a trade off : OB enthusiast seem to like articulation and lack of coloration but may miss punch and soundstage somewhat for a more immersive experience than only occur in big venue but not necessarily cope with sound ingineer mastering for a studio reccording !
Choose you evil...
Slam is an artifact of big woofers with a lot of power. Used to great effect in concert PA. Few musical instruments have that kind of slam - except maybe a big drum up close. Listen to a typical rock bass drum during sound check, the slam comes from a close mic, EQ, powerful amps and big speaker cones. The drum doesn't make that noise on its own. To get that kind of sound, you need a similar system.
As for "soundstage" some OB can do that very well. John Busch brought a pair of P.Audio 18" coax on OB to RMAF one year. He and I worked on the crossover there - tweaking and tweaking to get them right, then we would go around and listen to other speakers at the show. Every time we came back to our big OBs we were surprised at how good they sounded. Better than about 80% of the other systems in the show. They imaged like mad, great depth and strong positions.
Slam? Well we kept playing the track "Po Lazarus" from O' Brother Were Art Thou, which starts with hammers on the railroad. Bang! Bang! Like real hammer blows. So much so we got shut down by TAS who were in the room next door. 😀
Basically I agree that imaging and slam are not as easy to do with OB as with box speakers - but they can be done with some skill and hard work. I know, I've heard it.
As for "soundstage" some OB can do that very well. John Busch brought a pair of P.Audio 18" coax on OB to RMAF one year. He and I worked on the crossover there - tweaking and tweaking to get them right, then we would go around and listen to other speakers at the show. Every time we came back to our big OBs we were surprised at how good they sounded. Better than about 80% of the other systems in the show. They imaged like mad, great depth and strong positions.
Slam? Well we kept playing the track "Po Lazarus" from O' Brother Were Art Thou, which starts with hammers on the railroad. Bang! Bang! Like real hammer blows. So much so we got shut down by TAS who were in the room next door. 😀
Basically I agree that imaging and slam are not as easy to do with OB as with box speakers - but they can be done with some skill and hard work. I know, I've heard it.
Seems clear from this ardent discussion that the only "sim" you need (or the only model any two posters would agree on) for a dipole is a dull pencil on the back of an envelope to figure the wave-length impacted first (but to an unpredictable degree) by the shortest sneak-around dimension. All the rest is plain guesswork... until you install the speaker in your room.
B.
B.
Hi Pano.
When I talk about slam, it is about just in my head to cope with real acoustic instruments, jazz or rock drums or also indian tablas that are hard to render and is often my reality check when I benchmark two loudspeakers. I know it is also about group delay and treble harmonics for the impact feeling. So the OB behavior of the upper frequencies are also involved more or less in the discussion. I focussed on the OB bass for the topic and also because bass is often the main difficulty to do well imho.
Slam is maybe notbthe rigtht word and I only talked of the fundamental of tose notes, often refered as midbass (upper bass in correct english, circa 80 to 200 hz). I am not referring to any amped rock artifice in studios or concerts from the mixing of modern music. That is simply not my ref when I talk about hifi. At least not my goal.
I supose it is also an EQ thing for the power response but here I am only wonder about delay and room patern in the feeling perception assuming a good reccording/material
When I talk about slam, it is about just in my head to cope with real acoustic instruments, jazz or rock drums or also indian tablas that are hard to render and is often my reality check when I benchmark two loudspeakers. I know it is also about group delay and treble harmonics for the impact feeling. So the OB behavior of the upper frequencies are also involved more or less in the discussion. I focussed on the OB bass for the topic and also because bass is often the main difficulty to do well imho.
Slam is maybe notbthe rigtht word and I only talked of the fundamental of tose notes, often refered as midbass (upper bass in correct english, circa 80 to 200 hz). I am not referring to any amped rock artifice in studios or concerts from the mixing of modern music. That is simply not my ref when I talk about hifi. At least not my goal.
I supose it is also an EQ thing for the power response but here I am only wonder about delay and room patern in the feeling perception assuming a good reccording/material