I'm very interested to see the results of this. After lots and lots of reading I've decided that the SPL output of 3" full range drivers is enough for me down to bass support, but I'd like to make their output more omni. I've made a clone of Oliver's Demokrit which sounds lovely in my living room. I'm interested in ways to make full range units more omni without deflectors, though. A near ideal pointsize without crossovers >250 Hz is an interesting challenge. The dustcap/phase plug could perhaps be used in the paraline as Patrick is suggesting for the dome tweeter.
What do you think?
What do you think?
All the usual B&C dealers simply do not stock the DE5 or DE7. Although they have all offered to special order them.
Does anyone know what the optimum sound absorption device is?
In the second measurement posted above, I stuffed the space under the midrange cone with polyester fiberfill. (The driver is a Pyle PDMR5.) In the first measurement, there's no poly fill, the chamber is empty. The driver is those $2 2" midranges from PE.
I'm wonder if part of the very nice rolloff of the PDMR5 is due to the poly fill.
Based on my understanding of HOMs, we will not see any diffraction below 18khz in the Paraline. And I think Danley is right about this. I have a set of Summas, and I think I've become pretty adept at being able to 'hear' HOMs. And I don't think the Paraline has a lot of HOMs.
BUT...
The energy from the various devices may 'leak' into the cavity of the midranges. For instance, a certain percentage of the output from the compression driver will certainly find it's way into the midrange chambers, and we don't want that.
So, a substantial amount of sound-absorbing foam or fill may smooth out the response of the Paraline, at the expense of efficiency. (And obviously, for a hifi setup I'd happily discard efficiency for smoothness.)
Just some food for thought. I know Dave Smith from Snell has been discussing which sound absorption is ideal on here, but I haven't heard what the winner was. (fiberglass? reticulated foam?)
In the second measurement posted above, I stuffed the space under the midrange cone with polyester fiberfill. (The driver is a Pyle PDMR5.) In the first measurement, there's no poly fill, the chamber is empty. The driver is those $2 2" midranges from PE.
I'm wonder if part of the very nice rolloff of the PDMR5 is due to the poly fill.
Based on my understanding of HOMs, we will not see any diffraction below 18khz in the Paraline. And I think Danley is right about this. I have a set of Summas, and I think I've become pretty adept at being able to 'hear' HOMs. And I don't think the Paraline has a lot of HOMs.
BUT...
The energy from the various devices may 'leak' into the cavity of the midranges. For instance, a certain percentage of the output from the compression driver will certainly find it's way into the midrange chambers, and we don't want that.
So, a substantial amount of sound-absorbing foam or fill may smooth out the response of the Paraline, at the expense of efficiency. (And obviously, for a hifi setup I'd happily discard efficiency for smoothness.)
Just some food for thought. I know Dave Smith from Snell has been discussing which sound absorption is ideal on here, but I haven't heard what the winner was. (fiberglass? reticulated foam?)
The two buck midranges are 1.25" deep, and they don't quite fit under the Celestion. So that's about 1.125" deep. My CDX1-1425 is in pieces right now, so I can't measure it. In the pic I've inserted a 0.25" space beneath the Celestion.
The Paraline progressively has more diffraction at lower frequencies.
As far as "the optimum sound absorption device", there is none (save perhaps a black hole
) one has to choose absorption for a particular frequency range.
weltersys,
I have to agree with you on the comment about diffraction. The Paraline, like any other device becomes more and more omnidirectional as frequency is lowered until the waveform is equal to or longer than the mouth opening. This is true for any shape waveguide, whether touted as CD or exponential the rules stay the same. The only advantage that I am seeing here is that you have foreshortened the entire length of the waveguide and supposedly have perfect integration of the multiple devices. I don't believe any of that is actually true, there are many fallacies here, the cavity resonance of the mid devices and the effects on the compression drivers are much more sever than is being spoken of. I am not saying that these designs can't sound okay, but there are many aspects of this design that I question as a whole.
I have to agree with you on the comment about diffraction. The Paraline, like any other device becomes more and more omnidirectional as frequency is lowered until the waveform is equal to or longer than the mouth opening. This is true for any shape waveguide, whether touted as CD or exponential the rules stay the same. The only advantage that I am seeing here is that you have foreshortened the entire length of the waveguide and supposedly have perfect integration of the multiple devices. I don't believe any of that is actually true, there are many fallacies here, the cavity resonance of the mid devices and the effects on the compression drivers are much more sever than is being spoken of. I am not saying that these designs can't sound okay, but there are many aspects of this design that I question as a whole.
rvrazvan,
The rules apply for any size of this device. You can build the Parline for any size driver, you just have to size it accordingly. There is no rule that this has to be a full range system, this can be a design for a single driver such as a 15" driver. Most people in this thread are using this as a full range device with multiple drivers for highs, mids, and lows if you can design it to integrate at all the frequencies.
The rules apply for any size of this device. You can build the Parline for any size driver, you just have to size it accordingly. There is no rule that this has to be a full range system, this can be a design for a single driver such as a 15" driver. Most people in this thread are using this as a full range device with multiple drivers for highs, mids, and lows if you can design it to integrate at all the frequencies.
Sure. You can get 'in the ballpark' by modeling it as a radial back loaded horn in Hornresp.
You can also leave the back open to make it a back loaded horn.
You can also put a Parline on both sides of the driver, and end up with something similar to an H-Frame or a Bose acoustic cannon. The acoustic cannon suffers from strong resonances. The flare of a horn on both sides should improve that problem w/the acoustic cannon.
Art - are you just commenting on the 'diffraction' at the mouth? I.e., about what happens when a wave hits a slot (according to frequency)? Or are you saying that something is going on inside the paraline?
Thanks
SMF,
From my perspective the diffraction in the low frequencies is a function of mouth size, not the throat section of the paraline. But the principal of the Paraline is that it is working as a diffraction device at the slot for the upper frequencies loading into the waveguide. That is the reason that they height is what it is for the dispersion in the horizontal plane and becomes limited in the vertical plane.
What say you Patrick?
Steven
From my perspective the diffraction in the low frequencies is a function of mouth size, not the throat section of the paraline. But the principal of the Paraline is that it is working as a diffraction device at the slot for the upper frequencies loading into the waveguide. That is the reason that they height is what it is for the dispersion in the horizontal plane and becomes limited in the vertical plane.
What say you Patrick?
Steven
jerryo,
I have not heard these either. What I know is that this is borrowed from a pro-audio application for sound reinforcement with a coherent wavefront/ I don't really think that in its present form I would call it a high fidelity device. but I have not heard it so I could be wrong.........
I have not heard these either. What I know is that this is borrowed from a pro-audio application for sound reinforcement with a coherent wavefront/ I don't really think that in its present form I would call it a high fidelity device. but I have not heard it so I could be wrong.........
I think it depends on you personal preference. JGH summed it up nicely in his editorial "why hifi experts disagree"*
I personally listen to a lot of heavily processed music (EDM), indie music, and talk radio. Due to this, I've noticed that my listening content has virtually no sound staging, but a lot of bandwidth. (lots of EDM digs into the 20s)
So I don't obsess over soundstaging much. I *have* found that articulation and intelligibility is the one thing that can make all sources better. Even if you're listening to Lou Barlow on a 64kbps Pandora stream, an articulate loudspeaker will improve your ability to differentiate instruments, words, the studio, the microphones. Articulation gets you closer to it.
i am not aware of a better way to improve articulation than to use a wide bandwidth point source.
Here's a few examples of this:
- a line array can produce a large image. But the articulation is poor because there are multiple elements producing midrange frequencies, each at distinct points in space, interfering with each other
- My beloved Summas are quite articulate. In the range of 2khz to 16khz, the sound is radiating from a single point in space.
- A full range Paraline can potentially improve on the Summa's radiation in 2 aspects. First, instead of covering three octaves with one driver, it's covering five, including the critical midrange. Second, a Paraline is a smaller acoustic source. (and if we are trying to approximate a point source, smaller is better). For instance, a Summa reproducing 1khz is radiating sound from both the waveguide and the midbass, with a center-to-center spacing of 42cm, from a cabinet that's the size of a small refrigerator. Due to the very small dimensions of the Paraline, if it's playing 1khz the sound is radiating from a point in space that is a small fraction of my reference loudspeaker.
In summary, is a Paraline hi-fi? That depends on what your preferences are. If you want a radiator that's the size of a ribbon, that can do 110dB, and plays three octaves lower, this is the answer.
I do NOT think the Paraline is for you if ruler flat frequency response is your thing. For instance, the music I listen to is already heavily processed, and that's likely one of the reasons that ultra- flat direct radiators aren't my cup of tea. I like it loud and Prosound speakers fit the bill.
I think there's some substantial cosmetic reasons to use a Paraline. Due to the fact that they're flat and thin, they're an excellent complement to a flat screen TV. Or mount it on the wall. Or in the wall. Or use it as a room divider. Lots of options, places where horns would normally not fit.
* The high-fidelity initiate, bewitched, bothered, and thoroughly confused by the staggering selection of components he must choose from, often turns to a high-fidelity expert to assist him in assembling his dream system. The expert may be a local consultant, a dealer, or a magazine that the prospective buyer trusts as a source of accurate, down-to-ear information.
If this seeker of high-fidelity truth is wise, he will consult one expert and no more. The more expert opinions he gets, the more confused he will become, because every expert opinion will be different from all other expert opinions.
About the only thing that all high-fidelity experts agree about is that high-fidelity is supposed to be realistic sound reproduction. They may even agree that Marantz amplifiers are pretty good, and that Thorens makes a passable turntable. But try to pin them down about pickups, or other amplifiers, or tuners, or particularly loudspeakers, and one expert's preference is another one's anathema....
Full editorial here: Why Hi-Fi Experts Disagree | Stereophile.com
Last edited:
If you've never heard a Danley Synergy horn in real life, then you are missing out. Go find the nearest Danley dealer and listen for yourself. Only then will you understand why we are so passionate about this design. I can honestly say that Danley's so called PA speakers will trounce +90% of the speakers marketed as "Hi-Fi" regardless their price point. Wilson, B&W, and Avantgarde have nothing on Danley. The majority of Hi-Fi speakers cannot even begin to approach the dynamics, coherency, or efficiency of a Danley Synergy Horn.
Danley SH100B, Lavry DA10, MC2 Audio MC1250 - YouTube
The comment left behind by TerdFurg3zon in the above video speaks volumes. The SH-100B and SH-50 are not even the best models anymore. The SH-46 is even better IMO.
Danley SH100B, Lavry DA10, MC2 Audio MC1250 - YouTube
The comment left behind by TerdFurg3zon in the above video speaks volumes. The SH-100B and SH-50 are not even the best models anymore. The SH-46 is even better IMO.
It seems to me that if a considered design were to be finalised using a specific driver that gave good results, a Kit of parts could be made available, made from a CNC machined laminated material that made up the five layers of the design.
This could run as a "Group Buy" and would therefore be very useful in evaluating the efficacy of the Patented design by a wider group of people.
Just a thought!
This could run as a "Group Buy" and would therefore be very useful in evaluating the efficacy of the Patented design by a wider group of people.
Just a thought!