Why would one want to align drivers like this at all? I think it would be more beneficial to have controlled directivity that goes beyond what a single simple waveguide can do.
Hi tinitus,
Just try it for yourself, fast and easy😉
In my previous experiment, my tweeters come with short WG so it'd be more complex than domes. The closer they are, the more cancellation. More separation, the less cancellation but the vertical response is getting messy (as expected).
Hi markus,
Is there any effective WG which can do 180 degree of horizontal dispersion? Or we need more than one? What about the possible overlaps or holes between them?
🙂
Just try it for yourself, fast and easy😉
In my previous experiment, my tweeters come with short WG so it'd be more complex than domes. The closer they are, the more cancellation. More separation, the less cancellation but the vertical response is getting messy (as expected).
Hi markus,
Is there any effective WG which can do 180 degree of horizontal dispersion? Or we need more than one? What about the possible overlaps or holes between them?
🙂
We know that certain reflections increase spaciousness. This is obviously what a omni or dipole design wants to achieve. At the same time early reflections have a negative impact on intelligibility. So the ideal would be a speaker that creates on only certain reflections while minimizing others.
hmmm... what I like the most about omni is not the spaciousness. It's the very wide listening area, almost everywhere in the house, in which the timbre and tonal quality stay very stable. Such consistency can't be obtained from narrow dispersion.
By this character, so it sounds more natural to me.
OTOH I have to admit the ultimate detail (intelligibility) is not the best. It's not like a headphone. I'm OK with that.😀
By this character, so it sounds more natural to me.
OTOH I have to admit the ultimate detail (intelligibility) is not the best. It's not like a headphone. I'm OK with that.😀
A friend/speaker designer thought of the following: triangle shaped mid-range/tweeter planar driver...I estimate he was thinking of something around 8-10" tall, the base about 4" across, maybe a LF cutoff around middle C (261 Hz) or lower. Multiple drivers would interlock like a geodesic dome making a hemisphere shape resulting in a huge linear hemispherical radiation pattern.
Personally, being a fan of pure analog Trinaural, I'd likely prefer hemisphere L/R with each L/R hemisphere center facing the opposite channel (the flat side of the hemisphere parallels the nearby wall), with an omnisphere center. The front wall to back of the speakers = 4-6'. Yumm!
Of the top performing systems I've auditioned (mostly but not all at CES/THE Show) none was a monopole (well except for one). With only the rarest of exception I don't really consider monopole radiation high-end. Of the several different most widely known loudspeaker radiation patterns, natural acoustic instrument patterns most closely approximate a bipolar pattern...though my favorite loudspeaker radiation pattern follows Dr. Floyd Toole's latest recommendations, unknown in any commercial or DIY speaker except for one.
Personally, being a fan of pure analog Trinaural, I'd likely prefer hemisphere L/R with each L/R hemisphere center facing the opposite channel (the flat side of the hemisphere parallels the nearby wall), with an omnisphere center. The front wall to back of the speakers = 4-6'. Yumm!
Of the top performing systems I've auditioned (mostly but not all at CES/THE Show) none was a monopole (well except for one). With only the rarest of exception I don't really consider monopole radiation high-end. Of the several different most widely known loudspeaker radiation patterns, natural acoustic instrument patterns most closely approximate a bipolar pattern...though my favorite loudspeaker radiation pattern follows Dr. Floyd Toole's latest recommendations, unknown in any commercial or DIY speaker except for one.
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hmm, that's a simplification
at least around here, dipoles are popular mostly because of the box free design
what is commonly said about omnis, and repeated over and over, is in my opinion mostly based on heresay
its been said by Graaf, and me, that omnis may not yet be fully understood
and it might be the reason for "why are omnis not more popular"
most are copying others 'flawed' work/designs
noone seem to have actually exploided all possible aspects of omnis
The moment I read that post I was thinking:
-which reflections?
-what is "spaciousness"?
-early reflections are?
-intelligibility is?
..and of course my favorite:
-just who is "we" and how do "we know" it?
Yo - ro..........
Which speaker would that be?????? and I do have Dr. Toole's papers from the infinity site.
Yo, Thomas,
You will regret asking! 😀
I employ a 5-piece mode-flattening distributed sub array (ala Geddes/LeJeune with my own original Golden Ratio setup instructions)...also the main speakers are active high-pass X'd, dual pole, 135 Hz and 80 Hz. Even though the mains need extension only to 135 or so, I wanted them usable full range (like for location monitors) so the mains go as low as mid-high 40s.
I gave up stereo almost four years ago, favoring pure analog Trinaural (all three front channels are algebraically processed, IOW center is not summed mono).
The speaker is difficult to splain. Image ETA is about four weeks when the cabinet man finishes necessary changes (the same cabinets were formerly a vertically offset bipolar array).
Toole recommends ambiance drivers be direct copies of the main forward firing driver array. I'm pretty sure Toole presumes only single cabinet implementation, which would be extremely costly and complicated as you'll soon see (this and the lack of center channel application may explain the dearth of prior implementation of Toole's recommendation).
My mains are improved clones of the superb minimum phase 2-way $6500/pr French ASA Pro Monitors.
Per Toole the ambiance drivers fire 65-degrees outward (off-horizontal axis) from the main forward-firing drivers. The ambiance drivers are vertically offset for 7+ms (check that number, might be off) arrival delay to maintain main driver primacy. Obviously the vertical offset is easiest fulfilled by locating the mains above the ambiance drivers vs. vice-versa (always wanted to write that!)
So, fine, we solved the L/R array, but what about my Trinaural center channel requirement and/or HT application? No known center speaker has a nearby side wall, the closest boundaries being the floor and ceiling. So I fire the lower center speaker 65-degrees downward toward a pedestal base.
A 1" tall heel equals the speaker width and fastens close to the rear of the pedestal base. The 1" tall front face of the heel is angled to match the contact of surface (bottom) of the lower speaker. At the front of the pedestal is an upside down U-shaped bracket supporting the lower speaker (this bracket is open on the sides for side radiation of the ambiance drivers).
A flat horizontal platform rests on the upper front corner edge of the lower speaker. The platform secures with four triangle shapes (2 per side) resting on the top and rear panel of the lower speaker. This platform supports the lower platform of the stand between the lower/upper speakers.
If you aren't thoroughly confused without images, I'll see if I can do better! Believe me, if you saw my center stand prototype you'd know why I won't photograph it. Think of Dennis The Menace's soap box derby vehicle. Besides, the speaker cabinets are gone and it won't make sense without them.
The cool thing is my upper/lower speakers are discreet, each with separate 8-Ohm Xo. Meaning I can adjust system gain 5 dB (+3 dB for impedance, +2 dB mechanical gain with ambiance drivers connected) and compare with vs. without the ambiance drivers.
The stage/image size/accuracy and density collapses without the ambiance drivers, ditto detail, ditto sound outside the box, improved in every single audiophile parameter, no downside at all. You'd never return to any monopole regardless of cost and under no circumstance. I rate it the best overall architecture unless you gotta have planars (I've heard it all over a few decades including MBL). I love planars done right, but this is the cat's meow for my taste.
One last little tidbit is that this speaker architecture combined with the subs and the Trinaural integrates music and HT with no known compromise (requires retracting perforated screen and front projector). The acoustically transparent screen combined with good front wall to speaker spacing results in premium image/stage depth for video, especially music videos. Rather than exist as an acoustic impediment as is the case with any solid acoustically opaque screen, the screen barely exists in space for ideal 3D effects in the front. Add the surround spatial effects and you're cooking with gas.
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No reaction yet ? Graaf must be on vacation or in power outage, because if quoting this from ro9397:
with a little decryption it comes close to the center side firing principle (Stereolith if you want) with virtual side "hemispheric" sources, highly debated subject...see the graph for refreshing the memories.
BTW, the analogy with Trinaural stops here, the genuine Stereolith being more primitive, making no special treatment to the difference R - global or L - global.. But, with a more complex system, it's maybe possible to go much further, at the price of a very small listening spot.
PS : what's this Toole's recommended design ???
edit : thx for the info ro9637, but can you make a scheme or show pics too ?
with a little decryption it comes close to the center side firing principle (Stereolith if you want) with virtual side "hemispheric" sources, highly debated subject...see the graph for refreshing the memories.
BTW, the analogy with Trinaural stops here, the genuine Stereolith being more primitive, making no special treatment to the difference R - global or L - global.. But, with a more complex system, it's maybe possible to go much further, at the price of a very small listening spot.
PS : what's this Toole's recommended design ???
edit : thx for the info ro9637, but can you make a scheme or show pics too ?
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OK - Understand ya so far.
I'm guessing you are using Ampzilla's Spread Spectrum Tech thingie? I never did get around to reading how that little toy does what it does - but then I wuz never that hot at algebra. 🙄 In fact I didn't really understand the need for algebra until I got into calculus - and I still do things backasswards. 😉
I once dated a woman that took med's for that. 😀
Ahhhhh - a true believer! Buy a pair of $6k+ speakers - and them MOD them!!! I'm luv'n this!!!!
Oppps - I misread that - you said CLONED!!! EVEN BETTER!!!!!!!
Call me old school - but I like the ambiance speakers above the mains. 😎
OK - now I'm getting to feel like I just got off a big roller coaster ride. Which way is up???
Check my photo's in post#7. Ugly is my middle name!!!😱
You are having more fun with this than mere mortals are allowed!!!
I can't wait to see sum pictures. You are gonna need your own thread!!! 😎
It's said the center channel sees "true center" which is the common portion of R & L. (so the signals of far right and far left would not appear at this ideal center)
Now the basic (stupid) question: how to get it by an analog circuit?
First, if we sum R & L by a mixer circuit, what happens to the common portion of both channels? A commonly seen analogy is a diagram of 2 circles with some overlap between them, as what we see in the math class:
http://en.wikipedia.org/wiki/Set_(mathematics)
So, there should be "2 layers" in the area of overlapped. Is that right?
What's next? How to utilize this?
Now the basic (stupid) question: how to get it by an analog circuit?
First, if we sum R & L by a mixer circuit, what happens to the common portion of both channels? A commonly seen analogy is a diagram of 2 circles with some overlap between them, as what we see in the math class:
http://en.wikipedia.org/wiki/Set_(mathematics)
So, there should be "2 layers" in the area of overlapped. Is that right?
What's next? How to utilize this?
perhaps something like the inverse of this technique?:
Vocal Removal - Audacity Wiki
(perhaps we're getting OT, split off to a new thread?)
Vocal Removal - Audacity Wiki
(perhaps we're getting OT, split off to a new thread?)
Scott, I always thought you're familiar with psychoacoustics. All those terms are defined in numerous publications. See Blauert "Spatial Hearing" for a summary.