There is a alternative to EDGE from John Kreskovsky which is slightly more accurate – cheap but not for free
A, B, C, Dipole
IIRC EDGE does not account for the difference in path length at different mic positions
Michael
A, B, C, Dipole
IIRC EDGE does not account for the difference in path length at different mic positions
Michael
Why are you concerned about that "symmetrical peaks around a wrap through 180 degrees"? thing?
Its the "normal" filter behaviour thats displayed - nothing specific to the drivers in particular !
Michael
What's odd with the phase response? It looks like it should to me.... or maybe I missed something.
Might be you got confused by the phase response of the *impedance* and the phase response of the *driver itself* ?
Have a look at simus below to sort that out:
Michael
The ADAM monitors I have use something close to the 8" Peerless 830869 – I guess the only mod they made is magnetic shielding.
From what I can say, its a really good driver – as is its bigger brother – but again – there is something to gain IMO with respect to the "live" feeling...
On the other hand, not anyone is "rubber allergic", "friction allergic", "baffle allergic" etc....
Michael
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This is a very interesting design you have.
I was wondering - how would the sound be affected if the frame the drivers hang from weren't perfectly rigid? ie, what if the frame were sticking out of the top of a subwoofer for example? The frame itself would be wobbling back and forth a bit due to the LF energy of the subwoofer, which would set the speakers swinging back and forth like a pendulum.
Or if the frame weren't on a floor but on a desk or shelf or something that isn't perfectly stable, but moves back and forth a bit?
I was wondering - how would the sound be affected if the frame the drivers hang from weren't perfectly rigid? ie, what if the frame were sticking out of the top of a subwoofer for example? The frame itself would be wobbling back and forth a bit due to the LF energy of the subwoofer, which would set the speakers swinging back and forth like a pendulum.
Or if the frame weren't on a floor but on a desk or shelf or something that isn't perfectly stable, but moves back and forth a bit?
You possibly should get into contact with the users of the
"Prima Luce" or the
http://www.diyaudio.com/forums/multi-way/159731-beautiful-swingin-speaker.html#post2058806
"Roksan Darias"
http://www.diyaudio.com/forums/multi-way/159731-beautiful-swingin-speaker.html#post2058824
to explore how kinda swing system actually sounds when attached to a (sub-)woofer
On the other hand I possibly can answer how the interaction may be seen for non-rigid-frame mounting "in genereal".
LOL - even better though, you might try by yourself .
Take your Clarks, Reebok, Adidas or whatever, at the shoelace – do NOT move the shoelace "pivot" and give them a push with the other hand.
You will notice that your beautiful shoes swing the same (in frequency) after every push - no matter how.
Now try to shake your shoe with the hand that holds the shoelace. Try quick and try slow !
You will notice that when moving slow, your shoe will follow better – and starts to refuse to follow your movement the quicker you shake.
Now – to put things into perspective – take the shoelace off and knot it at the last hole – so as to get a way larger pendulum as before.
Repeat the experiments above and most likely you will be able to discover that your shoes are even more stubborn to quick movement.
Bottom line – the swing not only isolates the forces from entering the structure – it also isolates the movement of the structure shaking the speaker.
Without the use of any math you intuitively might have got the point, that isolation in either way is related to pendulum length.
A classical win-win situation I'd say...
Michael
"Prima Luce" or the
http://www.diyaudio.com/forums/multi-way/159731-beautiful-swingin-speaker.html#post2058806
"Roksan Darias"
http://www.diyaudio.com/forums/multi-way/159731-beautiful-swingin-speaker.html#post2058824
to explore how kinda swing system actually sounds when attached to a (sub-)woofer
On the other hand I possibly can answer how the interaction may be seen for non-rigid-frame mounting "in genereal".
LOL - even better though, you might try by yourself .
Take your Clarks, Reebok, Adidas or whatever, at the shoelace – do NOT move the shoelace "pivot" and give them a push with the other hand.
You will notice that your beautiful shoes swing the same (in frequency) after every push - no matter how.
Now try to shake your shoe with the hand that holds the shoelace. Try quick and try slow !
You will notice that when moving slow, your shoe will follow better – and starts to refuse to follow your movement the quicker you shake.
Now – to put things into perspective – take the shoelace off and knot it at the last hole – so as to get a way larger pendulum as before.
Repeat the experiments above and most likely you will be able to discover that your shoes are even more stubborn to quick movement.
Bottom line – the swing not only isolates the forces from entering the structure – it also isolates the movement of the structure shaking the speaker.
Without the use of any math you intuitively might have got the point, that isolation in either way is related to pendulum length.
A classical win-win situation I'd say...
Michael
Essentially the question I was asking was whether the normal tracking of acoustic phase with electric phase holds through mechanical resonance. Thanks for the simulations. I'm still somewhat unsure what happens with the acoustic phase, though it should follow the current's much flatter phase.
Fortunately today looks like a good one for some measurements.Nothing, I guess.
I haven't measured many woofers for electrical phase and, in my current system, the port tuning frequency and Fs are within 2Hz of each other---so it's especially unclear how much acoustic phase change is due to the port and not the free air acoustic response of the woofers. Since the resonance is mechanical it would make sense the electrical phase exhibited resonant like behavior but didn't undergo the full phase rotation I'm used to associating with resonances.An LR4 type phase wrap is, in my previous experience, normally associated with resonance. Also happens to be one of the phase correction profiles supported by the Arbitrator section of Frequency Allocator.
Not by default. You have to manually increase the speaker source density and watch for the simulation to converge. I've found densities of 8 are usually sufficient.
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Thanks for your answer.
As I was sitting here, swinging my Vans back and forth, I thought to myself....
What the hell am I doing here?
Then it occurred to me, why am I using a physical model, when I could be using.... Ghetto Engineering!
So I ran to the basement in my parents' house, grabbed some backup midranges I have for my surround system, dug out my old crate of Legos from my childhood, grabbed my spare amp, and whipped up this:
So I can sit here, kicking the desk with my knee, and seeing what effect it has on the sound. (As you can see I should be studying, but I prefer to distract myself with ghetto engineering - much more fun than real engineering)
I must say, I can see the appeal in a hanging speaker. Granted, these midranges are not really designed to be run fullrange, they've got a nasty 12dB peak at 1900Hz that I EQ'd away in iTunes, and they drop off pretty rapidly below 500Hz withouth an enclosure. All that nonwithstanding, they're still better than listening to my laptop speakers (which is all I have to listen with here).
These things sound tinny as hell, but somehow soooooo open and enveloping. I'm quite surprised.
Anyways, once my exams are over and I have more time and money, I think I will be experimenting more with hanging speakers, slightly less ghetto, using more & bigger drivers, and wood instead of legos!
Cheers from your neighbour state!
PS: Electronic music with HF flanges in it (ie, in the 5 digit Hz range) sounds rather painful, but the lower frequency range is really nice sounding (obviously - as this is a midbass). I'm thinking: swinging fullrange driver running from 500-20k, and (a) sealed or open / H baffled 8-12" woofer(s) for 500 down to 50ish.
PPS: Piano sounds beautiful!
On the other hand I possibly can answer how the interaction may be seen for non-rigid-frame mounting "in genereal".
LOL - even better though, you might try by yourself .
As I was sitting here, swinging my Vans back and forth, I thought to myself....
What the hell am I doing here?
Then it occurred to me, why am I using a physical model, when I could be using.... Ghetto Engineering!
So I ran to the basement in my parents' house, grabbed some backup midranges I have for my surround system, dug out my old crate of Legos from my childhood, grabbed my spare amp, and whipped up this:
So I can sit here, kicking the desk with my knee, and seeing what effect it has on the sound. (As you can see I should be studying, but I prefer to distract myself with ghetto engineering - much more fun than real engineering)
I must say, I can see the appeal in a hanging speaker. Granted, these midranges are not really designed to be run fullrange, they've got a nasty 12dB peak at 1900Hz that I EQ'd away in iTunes, and they drop off pretty rapidly below 500Hz withouth an enclosure. All that nonwithstanding, they're still better than listening to my laptop speakers (which is all I have to listen with here).
These things sound tinny as hell, but somehow soooooo open and enveloping. I'm quite surprised.
Anyways, once my exams are over and I have more time and money, I think I will be experimenting more with hanging speakers, slightly less ghetto, using more & bigger drivers, and wood instead of legos!
Cheers from your neighbour state!
PS: Electronic music with HF flanges in it (ie, in the 5 digit Hz range) sounds rather painful, but the lower frequency range is really nice sounding (obviously - as this is a midbass). I'm thinking: swinging fullrange driver running from 500-20k, and (a) sealed or open / H baffled 8-12" woofer(s) for 500 down to 50ish.
PPS: Piano sounds beautiful!
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A gorgeous take on the subject !
For sure worthily to enter Valhalla:
http://www.diyaudio.com/forums/multi-way/123512-ultimate-ob-gallery-6.html#post2110775
Michael
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Awesome.
I'm outside with the measurement gear (laptops and wireless internet, whee) and on close mic I'm measuring what looks like the usual LR4 phase rotation from the mechanical resonance of my 6.5 inch woofers (OEM variants of the Vifa XT18WH09-08, Fs is probably 38Hz). Too much dipole rolloff to take measurements at 1 or 2m, but 0.5m suggests the behavior holds up as one moves off the cone.
Conclusion: I need either much bigger drivers to measure or ones with higher Fs. Sounds like a description of the 8W4P and 15PW5 to me.
Awesome.
Thanks for the compliments guys!
I bet the real one I build won't garner as much attention as the prototype
Small update, a roadie showed up in the Legos bin:
Try these 8" PA's, then tell me what you find so I'll know exactly what to do with my pair
Monacor SP-8/150PRO
SP-8/150PRO
Hi there,
I'd like to share my latest woofer setup. This little swing is the simplest build I can think of, made of leftover ply (from baffle hole cut out in last project) as its base and a minimal skinny wooden frame. A steel wire support a bare woofer right at its center of mass so it's automatically balanced.
I'd like to share my latest woofer setup. This little swing is the simplest build I can think of, made of leftover ply (from baffle hole cut out in last project) as its base and a minimal skinny wooden frame. A steel wire support a bare woofer right at its center of mass so it's automatically balanced.
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Looks like just my bad luck to hit a temporary outage---I can see the image in post 115 now. Thanks anyway!
I was fooling around with compound pendulum periods and the parallel axis theorem and had just come up with the same solution when I noticed the email with your post notification. It's surprising to me how low the predicted frequencies are for short pendulums---for a 10cm pendulum I'm coming up with less than 2Hz for my 18 inchers and that's likely on the high side due to the rough moment of inertia approximation I'm using for the drivers. Is that consistent with your experience?
I was fooling around with compound pendulum periods and the parallel axis theorem and had just come up with the same solution when I noticed the email with your post notification.
It's surprising to me how low the predicted frequencies are for short pendulums---for a 10cm pendulum I'm coming up with less than 2Hz for my 18 inchers and that's likely on the high side due to the rough moment of inertia approximation I'm using for the drivers. Is that consistent with your experience?Yes. The fs of the whole suspension system is easily getting vvveeerryy low by such arrangement. The length requirements of the wire (or the likes) are often much less than expected.
10cm is about the length I had used on the suspension of midrange horn. And the wire in the pic above is only slightly longer.
10cm is about the length I had used on the suspension of midrange horn. And the wire in the pic above is only slightly longer.
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