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My latest music acquisition is Erykah Badu's new CD "Return of the Ankh". Great collection of songs, I'm loving it. What a groove!
While listening, I've noticed that she and her sound engineers were playing a lot with the sound during the production phase. One thing startled me: there are many, many sounds on this CD that create the illusion that the sound source is located somewhere outside of the regular soundstage (i.e. the sound is often not coming from between the left and the right speaker). Sometimes the effect is extreme, for example I suddenly hear sounds coming from the extreme right, as if I had a third speaker positioned all the way to my right. Sometimes I'm hearing sounds almost as if they're coming from behind me!
How's this possible? What did they have to do to achieve this startling and confusing effect? And is it mostly due to the Maggie's nature, or will other speakers also reproduce this mystifying effect?
Follow Ups:
Using the Carver hologram technology with a pair of correctly positioned speakers all program material will have sound that appears to originate outside of the soundstage. IIRC BC claims that one should even be able to hear sound coming from behind you, well not immediately behind you but nevertheless with some wrap around effect, (which I have heard).
Norman,
I would agree. My Carver C-1 preamp does this every time with great effect for me with my IIIas powered by a set of M-1.0t power amps.
I hear this effect all the time in well recorded film soundtracks. It's usually when it's raining or the wind is blowing outside in the film, or conversations and street noises when the film is in an urban apartment building. Cool stuff, and no surround sound speakers!
I'm jealous. I blame my apartment. Good thing I'm going to get orders soon. (hopefully to Ottawa).
When done in the mix, it's done with interaural crosstalk cancellation or manipulation of the head-related transfer function (for sounds behind you).
A stereo sound field actually extends 180 degrees, but in practice, it's truncated because the sound from the left speaker hits the right ear and vice-versa. Crosstalk cancellation adds an out-of-phase delayed signal to the opposite speaker, which cancels the interaural crosstalk.
You can produce this effect yourself with free software and it will work with any recording. Do a search for "ambiophonics." It's pretty cool to hear images extending at least 150 degrees, way past the speakers -- and I'm not talking about the kind of image spread you get from lateral reflections, which is what you're normally hearing when you hear sound beyond the speakers, I'm talking about what in audio terms is like going from an old 3:4 movie to a widescreen one.
I think there is more to this outside the speaker bit than reflections, I still think this has something to do with phase issues, since it is far more rare to get this kind of performance from steep sloped speakers.
Here is an interesting idea about the phase issue in recordings played back in omnipolars vs single or dipole in that the brain does not get a distribution of phase angles from which it can match auto correlated notes and locate sound radiating objects producing them from a monopole or dipole - you only get that from an omnipole in a reflective environment and from rooze type setups that create a phase distribution from the monopole mic's tiny sampling of the wave front:
I was taken in by that article of Robert Harley's but there was a discussion of it and somebody read the patent. Seems all he's doing is (primitive) crosstalk cancellation. You can do it better with the free Ambiophonics software, even better than that with Princeton's no-longer-free BAACH filter.
The role of time alignment/group delay in imaging is something I don't understand -- that is, I don't know whether it improves it or not, as long as the group delay is the same for both channels, since the brain does use interaural time differences (relative phase at lower frequencies, useless higher up where the wavelength is small compared to head width making the directional information ambiguous). Some recordings preserve this (e.g., dummy head or ORTF head-spaced cardioids), some don't (e.g., spaced omnis, in which the relative phase is randomized or pan-potted multiple mono).
I've seen it said that polar phase response is important to imaging. This would be because as you say the brain has to match the reflection up with the direct sound to determine that it's ambiance and extract information from it. If the polar amplitude response goes off, the polar phase response will as well, so who knows where one leaves off and the other begins. However, logic suggests that the brain determines this by using the neural network equivalent of a tapped delay line, and subtracting signals at t, t-1, t-2, etc. to some limit, then seeing if they null. And I'd guess that what it does by way of being able to do this simultaneously in multiple frequency bands, over different apertures, etc. is constrained by evolution, that is, by natural phenomena in which the group delay of a reflected image is generally the same as that of the source. In any case, as I said in an earlier post, I don't think different crossover alignments tell us all that much precisely because they do radically change the polar amplitude response, so we're left with that ambiguity. And we do know that polar amplitude response is critically important to matching the reflections with the source, there's much on Linkwitz's site about that. Maybe someone has done some experiments to resolve it, but if so I haven't seen them mentioned.
I think the QOL concept is different from what you are referring to in cross channel cancellation tricks.
It may have similar end results to a degre when used in stereo, but it is not what the target is. The application is identical in mono too and seems to have the same result - other than stereo effects.
The idea is to let phase correlated material that would otherwise cancel out as it comes out of a speaker to remain. The signal that is created and added to the otherwise unaltered original is the sum of phase shifted freq bands supposedly in 45 deg increments. the result is that you have particular phase correlated content be reinforced and that signal added back in to the original, so you have 1db and up to 5db higher output as some material that would have been cancelled coming out of a speaker is not cancelled.
Hmmm . . . I've been relying on second-hand knowledge here, first the review then someone who said he'd read the patent application. I found it but it's quite verbose and I haven't had time to read very far.
I think you mis-linked. I like the bit with the umbilical cords, cute.
Well I tried just about every combination - poles forward, poles backwards, tweeters in, tweeters out, tweeters wired backwards, tweeters wired normally - no luck on broadening the sound stage. Some interesting things - I first wired the tweeters out of phase, and didn't much notice the difference. I put it back, and thought "wow, that's better." did it a couple of times to confirm - I really only notice the difference going one way. Only clear loser was tweeters in. Poles facing the room won out slightly over facing the front wall (sounds louder, so I figure less clipping on the amp since I don't have to turn it up as much, and the sound is more at ear level, vs higher for the poles normal config).
What do you all think - other than some of the peculiarities about JBen's room configuration, what can I do to create the environment for that surround-sound effect?
Hmmm, let me not assume things and do a "basics check". The following are non-room related things that affect imaging. This will be rushed because I am expecting some visitors, so I may forget some things but not the important ones. In order of influence:
1. Power cables of correct guage. Best example. First Denon receiver I had. No imaging to speak of. The surrund effects were barely perceivable. False solution: I bought another more powerful Denon and the issue was gone. Why false? Much later I discovered that the power cable sold to me with the original Denon was a computer cord, 18 GA. Later tested the same offending receiver with a 14ga cord. Imaged like a champ. As a result, I replaced ALL power cables with 14ga. Improved imaging further. (In the process discovered that the SACD player was in fact supposed to have a 14ga cable, not the 18ga they sold it to me with...bass and dynamics jumped, imaging finally surpassed my cPlay enabled PC.) Whatever you may have bought second hand or store demo IS SUSPECT.
2. Speaker cables: too close to transformers or other power sources. Case in point: A single walwart (like the transformer for a hard drive) can flatten and/or shift imaging if it gets to close to speaker cables. (I allow no more than 6" proximity now. Even with shielded power cord)
3. Power cables: (Shielded vs non shielded.) Later replaced all 14ga non-shielded with some 14ga shielded that Dawnrazor mentioned. A few benefits ensued including notable gains in image stability and overall soundstage.
4. Interconnects, obviously, the analog RCA. Regardless of quality, keep away from power lines, transformers and the enclosures of the equipment.
5. Walwarts or power appliances on the same circuit contaminate. iPad's, among other, are very offensive. Power conditioners help but are not always effective.
6. TV RFI of my plasma is not as terrible as I have seen elsewhere. Shielded power cord helps grandly. Managed distance helps also.
7. Some power amps with toroidal transformers can be affected by CableTV or Satellite incoming signal. TOTAL disconnection (cable from box, box from wall) can tell. If an issue is found, filters are avalable that help.
Visitors arrived...but you get the idea. Cable & power managment is key.
Haha that's about everything!
1. Every power cable I have is suspect :-)
2. This has to be an issue in the jumble I have
3. Probably good here
4. Same as 2
5. Half the apartment, including the microwave and TV, are on the same circuit. I kid you not! I'd have to run an extension cord from my bedroom to get on another circuit. I haven't gotten a power conditioner yet. Should search audiogon, but I'd prefer to stick to low cost solutions for now and my surge protector. But I will get one eventually.
I think when I get a house I'll hire an electrician to do some rewiring and have a couple dedicated wall sockets for audio-only.
I played the demo tracks on the ambiophonics web site...sounds coming a few feet left and right of my imac (built in speakers); pretty crazy!
It's amazing, isn't it?
At least, that's what I remember from when this was discussed earlier.
FM dose this all the time...some time i stop an get the lites out an point were i think the sound is comeing from....an it two feet outside of my MG2c.....tweeters out... room W..18'...2c 13'inside to inside...off back wall 5'... room L 25'....my head is 15' to cen...
R Waters CD woks every time...miny others..thanks for the post
For Q sound to work properly the system must be very phase coherent. Also some people can hear the effect while others won't. If you have a system that really screws up the phase response of the music you will get sound from all over the place. The Roger Waters cd is one of the best examples of using Q sound.
Alan
You mean FM radio, Tyu? One of these days I am finally going to find and install the darn antenna. I get off the car listening to a concert and then I can't continue listening at home. Dumb...and lazy.
LOL! I do something like that...I close my eyes and point the laser pointer at the sound outside the MMGs after a while. Then I open my eyes to confirm. The first time my wife saw me doing it she started looking for my straight jacket.
I use tweeter-in in this room. The difference is not significant here and I get a better center rendition. Check this link below for the room layout as it was early last year, not much has changed since then. I have to update and add other details that I think contribute in this room.
hhscott355 pretuner....60years young...same tubes sold when new..all stock....lot of fun...how about the Brain...gives us all these great tones...in space... i well look at you setup...thanks
What a little jewel have we here! Long, very long ago, as a high school student, I envied a neighbor's ability to get such a delightful sound from his Klipschorns. At first I thought it was the Dynaco tube power amps he had. However, he insisted the HH Scott was the real hero. The darn thing also had FM sensitivity that beat the living daylights out my father's huge Grundig. (That Grundig, when I finally got my hands on it to dissect it, showed me the first electrostatic tweeter I had ever seen).
Yup, at the end of the day, it is the brain. We just fool around pretending that we control what it does. It is both fun and folly that it gets us here discussing as if we "knew" things.
This hhscott tuner dose a great job ....But the star is the hhscott 299c
pre/amp never have had a All stock tube amp with all the tubes that scott put in...over 60yeas ago ...I never heard any thing like it.. now i drive my Old B&W DM16s...big full bass..lot of fun..It only 30 watts but it well drive the Magnepan ture ribbions vary well... Thats just the ribbinos.....It seems to have more power tha a Dynaco.ST70....an it outputs are the 7591s...go figg....This Amp puts a lot of thing out side of the maggys nomatter if the tweeters are in /out
I looket at you room...tuff...12'WX25 long...but you got it working thats all matter
thanks for your time an goodluck on you woodwork
The 299c I never saw before. Given HH Scott's design prowess at the time, it would not surprise me if they project more power than the ST70s. I liked the overall sound of the ST70s. However, I was not successful in them driving the midrange/tweeter combo (of a bi-amp set that I had in the 80s). To be fair, the volumes at which I played some things in those days...
You know, the room was not as much of a scare when I first considered buying the MMGs. OTOH, the fact that I would have to live with a TV in the middle was my very worst concern.
Long story short is that it may have been a blessing in disguise for it facilitates great center imaging. Luckily, the late Al Sekela had had the same challenge and threw a few good ideas my way.
Also helping, though I did not realize it at first, was the truncated corner wall on the left side. Once I matched on the other side, stuff beagn to fall in place rather easily.
Thanks; the wood work went fine on the most important aspect: the sticks that do the actual sound improvement job. These were cut just as precisely as I needed. They will be hidden from view so we did not stain them.
On other, more exposed pieces, things did bomb out, at least for the day. The test for the wood stains that I thought I'd use made us reconsider. I'll have to test other alternatives...but "pretty" can always wait on my book. I just need them to sound right, for now. : - ))
I just played "Hotel California" from "Hell Freezes Over" again, this time plugging my right ear. The crowd, which was limited to the edge of my speakers, suddenly blossomed to all around my left side. I heard whistles from BEHIND me. Freakin' awesome. Going to play with placement and see if I can't figure something out.
Awright! We're getting somewhere.
I was hoping to find my installation disks for Flash (creator) which got corrupted in the PC, but they must be in the storage. With Flash, I may be able to illustrate, by animation, the appearance of items on my soundstage as some pieces are played. I have many examples that correlate with other Maggies and other box speakers that I've played that same music through.
In the meantime, for further reference at the start of this Hotel California version, before the singing begins:
- As the piece opens, the first guitar chords appear centered, about 2ft behind my TV (which always behaves as if it were not there, sound-wise)
- A guitar solo then begins a couple of feet behind the right MMG
- The bulk of the crowd is spread from left outside that MMG to right outside that MMG, but on the other side of the back wall (sliding door).
- The low-frequency amplified/miked conga beat is strong, dynamic and beefy. The MMGs don't need the subwoofer to project most of its impressive bass and that's how I prefer it (thought the subwoofer will reveal more low-end ambience, synthetic as it is). This beat shows left of center and I perceive it as slightly forward of the crowd but still outside the room.
- The normally recorded side of the conga pair is sent mostly to the right channel and shows about 4ft behing that MMG.
- The crowd blooms at times, with a bias towards the left side of the room. Some of the whistling is also left-biased but appears slightly behind me and very high above...as if there were various levels in the hall and someone whistled from a level above. This particular whistle location is very reapatable. I've heard it hail from that same spot with 1.7s, 3.7s, 3.6s, LFT-8bs, Nola Baby Grand Ref, B&W 802Ds and a couple other speakers, all in diffrent rooms. So, I supect the recording engineers did not do this by accident.
Yeah I failed miserably. I managed to extend the crowd beyond the speakers by rotating the speakers out so the edge of the speaker are facing the couch (not as good as plugging one ear, but still impressive), but it completely destroyed the center imaging. I ended up settling on moving the speakers wider apart.
What type of room dynamics do you need to get that faithful reproduction outside the stage created by the arc from speaker to speaker?
Ok, just keep trying...little by little one starts getting an improved sense for what might work.If you mean the drawing with the curved arrow, it is a little more elaborate than just the room. Luckily, at some point in the future you may be able to shoot for something like this.
The reason is that to obtain it, room and electronics go into a "tuned state" First, I maximize every room feature that can help in this particualr situation, including exposing the sliding door glass. The latter is usually a no-no in audio but I get away with murder by compensating at the corners. It works, but it still can get too bright with bad material.
The other key element is that I then switch my bi-amp configuration to one that places both drivers in the same polarity. The resulting frequency response curves are virtually the same when measured with a mic. However, the "same polarity" xover version will enhance depth and layering towards the back. It does help to be able to measure the actual frequency response because one "sees" how the drivers work together and separately.
I don't know for sure if this would work with 1.6s but at least you already have a great xover to try it with...but later. First you have to get the hang of what you have.
Which reminds me, if something is not set right in that xover, you may get great imaging showing up in China...LOL!...but not really where you want it. So, keep learning about its capabilities, limitations and related things.
Edits: 03/19/12
Usually something that out there is from a q-sound recording.
The liner notes on the CD are printed using microscopic font, so I'd need a very powerful microscope to read it. Sorry, could not decipher whether they mentioned q-sound or not.
I'll let the engineers explain the speaker physics & psychoacoustics involved.The effect that you describe is very common in quite a few recordings at home. In fact, I place bets with friends that stereo can do surround, and win all the time in my place.
However, it is not only the Maggies that can do it. Depending on how the recording was made, many good boxes can deliver the experience. Still, planars are much better at it, as far as I've personally heard.
Edits: 03/16/12
However, it is not only the Maggies that can do it. Depending on how the recording was made, many good boxes can deliver the experience. However, planars are much better at it, as far as I've personally heard.
Yeah, I remember a recent audition I did for the Naim DAC. At one point, the sales rep told me he's gonna play some Roger Waters track, and alerted me to pay strict attention to the 'surround sound' effect that should be delivered (he was using Totem speakers). I remember trying real hard to hear the much ballyhooed surround sound effect, but for the life of me couldn't detect even a single sound coming from outside of the regular soundstage zone. But I just played along, telling the rep how impressive Totem speakers were;) I didn't want to ruin his presentation...
But at home, with Maggies, for sure, these wonderful little surround sound effects keep pleasantly surprising me and often startling me:)
An example with a box speaker. "Hell Freezes Over" CD, The Eagles.The rendition of Hotel California, in concert, has many charms in my system. I use its first minute or so as part of my core test music.
Among these charms, the audience extends outside the walls behind the MMGs but some of their applause and some of the whistling hails from above and behind me at the sitting position.
At a friend's, his B&W 802D speakers do pretty much the same. While the audience behind the speakers is not as deep, from behind and above me I hear a similar surround effect in stereo.
OTOH, what the 802Ds cannot replicate there is the soundstage depth and layering that I get between the MMGs and their behind-the-wall far end, as I get at home. Within this soundstage at home, each player and instrument has a 3D position and none of it comes from the MMGs or anything in between them.
Another example I just remembered is the Telarc SACD Sampler 3 disk. In the stereo layer, the first track is rich in spatial effects and it starts with sound that comes from the back as well as, later, sound from the sides, close to the sitting position. Both the MMGs and 802D display them, each with their own personalities.
I wish the 802D were not so heavy becasue I'd be curious to see how much of my room config makes for the great imaging I get. These B&W, for being boxes, do very good imaging despite their current placement restrictions in my friend's family room.
Edits: 03/16/12
Do you have tweeters in ... or out?
Thanks,
Andy
Hi Andy! Tweeters in.
alas, I don't hear " some of the applause & whistling coming from above & behind me "!! :-((
So I thought mebbe that was an artefact of you having your tweeters out?
Regards,
Andy
Is this the same disc?
http://www.amazon.com/Hell-Freezes-Over-Eagles/dp/B000000OU0
There are other recordings of the song that do not display similar sonics.
.
You had me worried for a sec. The effects come through even in good box speakers. Maggies make it better still.
I am going to bed early, only 1am, not my usual 3am but I have Maggies work to do tomorrow and it starts at a friend's at 7am. We are cutting the new wood.
I just played that song - I get just past the outer edge of my speakers - not much more. Though one of my favorites is the first battle scene in Master and Commander. The shot below decks with the gun crews, you can hear the sailors on the weatherdecks running about. Sounds like it's coming from the upstairs apartment.
"Though one of my favorites is the first battle scene in Master and Commander."
I love it while watching the movie here, also! However, I have not tried in stereo, only in surround (which I don't use for music).
I did tell you that at least one of Peter Gabriel's pieces does that here also, didn't I? It builds a dome of sound that spans from behind the MMGs, over the side walls to their outsides and all the way to well behind my sofa. One hears the soundfield and one also gets specific items hailing from around and from above...in stereo.
Which one? I have a center for movies btw.
LOL! PE, I discarded the center speaker long ago because I don't need it.
This is edited from the post where I mentioned it earlier [adding context clarification in brackets]:
One of the examples was Peter Gabriels's UP in SACD Stereo. A friend once challenged that I HAD to be using the multi-channel layer (which I never use). No way could stereo do this, he said. I won a case of beer.
...The effect on "Growing Up"... This piece is one I used many times. It creates a sound bubble of surrond sound that includes the ceiling. Awesome; and I did not use the subwoofer which [if I do] adds even more resonance "air". [at the expense of other things that I like without it]
--------
I then added that the CD layer of the SACD recreates much of this effect. In other words, SACD format is not the determining factor for this to happen. It is the way the recording is made. Ergo, if you have the CD, you may be able to hear this.
Yeah, I imagine now that I have a proper setup, I can get by just fine without mine. Might even be better without it. Whether by accident of design (unlikely) or accident of rookie ears (likely), it works seamlessly with the Maggies. Wouldn't be hard to turn it off on the receiver though and test the differences. In fact, I wonder if it'll give a better psychological center since the channel wouldn't be a point source from the bottom of the TV. OTOH, the center of my image shifts left when I move left and shifts right for when I move right, so the center might be best for those off-axis.
I have *a* "Growing Up" track on disc one of Gabriel's "Hit and Miss" collection. It doesn't exceed beyond the soundstage. It's almost certainly a different mix (in fact, it says "Tom Lord-Alge Mix"), but I think we've already establish your room/ears have a better sense of the surround. I'm probably going to move within a few months. Going to rent a house. Priority #1: decent living room dimensions.
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