Depending on the magnetic gap lines of flux orientation, either clockwise or counter clockwise windings can result in a + signal moving the diaphragm forward.
It is possible for a voice coil to be flipped in manufacture, which reverses the winding direction and polarity. I once received a factory recone that had that problem, since then I have always checked woofers with a 9 volt battery to confirm correct polarity before closing the box.
The diaphragm is usually impossible to see on a HF driver, and even if visible the movement is generally too little to be detected by eye with a battery test, though the "click" noise it makes at least tells you if it works or not.
Still awaiting Celestion engineering to answer several questions regarding the ferrofluid used in the CDX14-3050 magnetic gap before I correct the polarity reversal. "Dr.Decibel" from Celestion did confirm that there was no change in polarity convention between the 8 and 16 ohm diaphragms and that + voltage applied to the red terminal makes the diaphragm move towards the throat, but has not confirmed whether ferrofluid is used in both the 16 ohm variant and the standard 8 ohm.
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I looked at the phase response in Smaart and determined I'd put the diaphragm in upside down
.
Nate Hansen requested a more detailed chart.
The chart is the SynTripP with secondary horn extension horizontal dispersion measured at 2 meters above ground, mic at four meters. Ground and building bounce makes the response look quite a bit rougher than later tests done at four meters high.
The chart is the SynTripP with secondary horn extension horizontal dispersion measured at 2 meters above ground, mic at four meters. Ground and building bounce makes the response look quite a bit rougher than later tests done at four meters high.
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Glad you enjoyed it!
Tests at four meters high will show the frequency polar response is even better than it appears in the past tests, but I have about 50 hours of other work to finish before any more testing will happen, and I'm more excited about a "further development", than further testing of the SynTripP.
Further development will include the "SynTripP 3D" (working title) now in the design stage, stereo sound from a single cabinet. It won't have the output potential of the SynTripP, but will use very affordable components, total cost per cabinet should be in the $100 range.
The SynTripP 3D will use a variant of the old Phantom Stereo concept I was first introduced to by Yanni (Chryssomallis) before he became rich and famous. At the time, around 1975, he was playing with the Minneapolis space rock band "Archangel", a few years before joining "Chameleon", another great rock band.
Yanni had simply connected the "+" of a rear ("Phantom") speaker to the "+" on one side of his receiver amp, the "-" to the "+" on the other amp side, resulting in only the L/R stereo difference information is heard from the Phantom speaker, a kind of "triphonic" effect requiring no encoding. Although I consider it an "effect", the Phantom image can be quite revealing of recording techniques, as L/R phase differences are discreetly heard from the Phantom, while a true mono recording results in no sound. The Phantom has one advantage over standard L/R stereo- no matter where you are in the room you can still hear a stereo image, of sorts. The Phantom connection works fine with all amps that use a common "-" ground connection, but may be problematic on some newer "bridged" amp designs that isolate the "-" from the amp chassis ground.
The SynTripP 3D can be operated in multiple modes:
A) "Wide" mode: a 180 x 40 degree horn requiring only one channel operation.
B) "Beam Steering" mode: Controlled patterns from around 180 x 40 to 40 x 40, requiring a minimum of two channels of amplification and DSP, and up to 26 channels for more precise control in both horizontal and vertical beamwidth, similar (on a small scale) to what EAW's Anya system does.
Robert Scovill is loving the Anya on the Tom Petty "Hypnotic Eye" tour.
EAW: Eastern Acoustic Works | Robert Scovill Talks About Anya at Fenway Park - EAW: Eastern Acoustic Works
Robert has pretty much the same goals in live reinforcement (and recording) as I do, other than that darned weight and size issue that precludes me from using large scale cabinets. I still can't hear the name Anya without immediately thinking of Frank Zappa's "Didja Get Any Onya?", sung by Lowell George on the album "Weasels Ripped my flesh".
C) "90 degree" mode: The two outer side firing horn cells are disconnected from the amplifier and shorted out, limiting the coverage to the 2 (or 3) center cells, requiring only one channel of amplification.
D) "3D Phantom" mode: Left /Right difference signal is sent to the side firing outer horn cells, requiring a minimum of two channels amplification, processing can be either done with a simple passive network consisting of some resistors or potentiometers (volume controls), or with a four channel mixer with one polarity reversed connector. Using volume controls allows the stereo "width" to be completely adjustable.
E) "3D Phantom Dipole" mode: As in "D", but the outer cells polarity is reversed, resulting in a wider divergence of the stereo image from the main output.
F) "Left/Right/Center" mode: LRC from a single cabinet, requiring a minimum of three channels amplification.
Modes A,B & C will be useful when using the SynTripP 3D as "fill" speakers for PA, or as speakers for home theater.
As a musician, having to lug around 2 speakers to achieve stereo is an added burden, especially on postage stamp sized stages, when crammed in a corner, or in a small rehearsal space. Although the spaciousness the stereo image two speakers can provide is great, a single point source for everything but the reverberant content is actually the best way to reproduce vocals and instruments.
The idea for a single "3D" speaker using a line array format had been bubbling around in my head for a while, then on 11/7/14 it occurred to me that it could be done using horns, which will work much better in most of the venues it will be used in. I'd already repurposed one of my Hyperboline speakers to make a pair of mini line arrays:
http://www.diyaudio.com/forums/multi-way/236037-dirty-dozen-line-array.html
I'll be able to use the other three and parts of their horns to make four SynTripP 3D, just need to decide what lightweight (and cheap) woofers to use below 200 Hz or so.
Art
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Is the 3D thing anything like this?
http://www.diyaudio.com/forums/full-range/223313-foam-core-board-speaker-enclosures-239.html#post3961261
Yanni wasn't the first to use it Nagaoka has the single speaker stereo SSS concept from way back.
http://www.diyaudio.com/forums/full-range/223313-foam-core-board-speaker-enclosures-239.html#post3961261
Yanni wasn't the first to use it
Nagaoka has the single speaker stereo SSS concept from way back.
Not much like that, the SynTripP 3D topology will sum the L/R for the center, and use the difference between L/R for the horn loaded side firing speakers, so the HF difference information will primarily be heard reflected from side walls.
After thinking about it more, probably will only build one as a rig for my Vocals/Theramin/Guitar/Keyboard/Drum gigs.
I still plan to build four conical horn front fill speakers, but since frequencies below 200 Hz are hardly needed (plenty of LF "spill" from the mains) they each won't require anything but a dozen "full range" speakers feeding 3 or 4 cells with a conical dispersion of around 40 x 60.
Actually, that is what the SSS matrix topology proposed by Elias does. He just added a LPF for the center channel to make more of the HF content reflect from side walls.
More info here
https://dl.dropboxusercontent.com/u/2400456/html/Elias_Pekonen/SingleSpeakerStereo.html
More info here
https://dl.dropboxusercontent.com/u/2400456/html/Elias_Pekonen/SingleSpeakerStereo.html
The SynTripP, as built is 2-way 2-part virtual single point source horn, connecting the two woofers separately to L and R channels would not effect much change to the output, as both drivers "fill" the horn equally. The result would be poor, reducing coherency due to phase differences between L/R combined together, with little image change compared to a mono signal.
The (unbuilt) SynTripP 3D will use separate side firing horn cells sharing a common horn mouth with the forward firing center cells. When completed, I'll create another post describing it in detail, as it is a completely different design using different drivers serving a different application than the SynTripP.
I probably should not have even mentioned it, as it is presently #15 on my "to do" list, with 60 (to 120
) hours of work before it is even started. Art
I'm currently in the "thought" phase (ie; ADD making me review all possible alternatives and yet prohibiting me from doing anything fully) of my home theater 'baffle wall' for LCR options.
I posted on PETT forum earlier today asking some basic questions about the synergy horn method. Up until last night, I was pretty set on a BMS 12" coaxial design for simplicity. But, I wanted to check the synergy horn idea as well. Someone over their mentioned your thread here. I must say...
WOW!
The amount of documentation you've provided is stellar. So, I have to ask... is this something you would mind sharing dimension/geometry details so we can *ahem* copy your work? I understand you probably would rather not let someone reap the benefits of your hard labor. I just can't help but ask. Practically every single one of your requirements for your build are perfectly in line with mine. Ideally, I'd like to keep a $400 budget and achieve high efficiency and output down to 100hz where subwoofers would then take over. And like you, I LOVE DIY but after years of this stuff, I have reached the point where I'm okay using existing designs that have the technical data to prove their merit.
So, to summarize...
Your efforts are astounding.
The results look awe-some.
Where's the tip jar?
Do you have BOM/schematics for us to clone your design?
If the answer to the latter is "no", that's understandable. I just can't not ask.
Thanks in advance, and keep rocking.
- Erin
I posted on PETT forum earlier today asking some basic questions about the synergy horn method. Up until last night, I was pretty set on a BMS 12" coaxial design for simplicity. But, I wanted to check the synergy horn idea as well. Someone over their mentioned your thread here. I must say...
WOW!
The amount of documentation you've provided is stellar. So, I have to ask... is this something you would mind sharing dimension/geometry details so we can *ahem* copy your work? I understand you probably would rather not let someone reap the benefits of your hard labor. I just can't help but ask. Practically every single one of your requirements for your build are perfectly in line with mine. Ideally, I'd like to keep a $400 budget and achieve high efficiency and output down to 100hz where subwoofers would then take over. And like you, I LOVE DIY but after years of this stuff, I have reached the point where I'm okay using existing designs that have the technical data to prove their merit.
So, to summarize...
Your efforts are astounding.
The results look awe-some.
Where's the tip jar?
Do you have BOM/schematics for us to clone your design?
If the answer to the latter is "no", that's understandable. I just can't not ask.
Thanks in advance, and keep rocking.
- Erin
The dimensions are in the development thread:
http://www.diyaudio.com/forums/multi-way/262838-synergy-tripp-10-a.html
They evolved a bit so you will have to look at the latest design. However, the final port dimensions for the bass reflex portion are perhaps a bit different. I don't think the difference is significant though.
http://www.diyaudio.com/forums/multi-way/262838-synergy-tripp-10-a.html
They evolved a bit so you will have to look at the latest design. However, the final port dimensions for the bass reflex portion are perhaps a bit different. I don't think the difference is significant though.
I'm currently in the "thought" phase (ie; ADD making me review all possible alternatives and yet prohibiting me from doing anything fully) of my home theater 'baffle wall' for LCR options.
I posted on PETT forum earlier today asking some basic questions about the synergy horn method. Up until last night, I was pretty set on a BMS 12" coaxial design for simplicity. But, I wanted to check the synergy horn idea as well. Someone over their mentioned your thread here. I must say...
WOW!
The amount of documentation you've provided is stellar. So, I have to ask... is this something you would mind sharing dimension/geometry details so we can *ahem* copy your work? I understand you probably would rather not let someone reap the benefits of your hard labor. I just can't help but ask. Practically every single one of your requirements for your build are perfectly in line with mine. Ideally, I'd like to keep a $400 budget and achieve high efficiency and output down to 100hz where subwoofers would then take over. And like you, I LOVE DIY but after years of this stuff, I have reached the point where I'm okay using existing designs that have the technical data to prove their merit.
So, to summarize...
Your efforts are astounding.
The results look awe-some.
Where's the tip jar?
Do you have BOM/schematics for us to clone your design?
If the answer to the latter is "no", that's understandable. I just can't not ask.
Thanks in advance, and keep rocking.
- Erin
Hey Erin,
I have Kefs here, and I have some DIY Synergy horns I've built.
Kefs are pretty darned good.
I'm not saying you'll be disappointed with the Synergy horn; but I *am* saying that you're reaching the point of diminishing return here.
To my ears, here's how they rank:
1) Synergy Horn
2) Kef (close, but not quite. But really, REALLY close.)
3) B&C 5" coax
4) B&C 8" coax
TLDR: Your current speakers are really nice. If you invested six months building some synergy horns, the difference will likely be subtle.
P.S. If you intend to use the Synergy Horns for PA, then ignore everything I said. My comments are based on using Synergy horns for the home or the car. In a PA scenario, they'll crush a KEF.
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There is something very special about the sound from a synergy - the directionally of the horn reduces reflections from the room and increases the signal to noise ratio. Noise being reflected sound. To have then coherency of the point source and the super high sensititivity (reduces distortion as you play with less cone movement), it all comes together with effortless dynamics. I have not heard an open face driver speaker that is as good. I have not heard KEF's but the synergy is definitely the best speaker I have heard.