The amount of misleading "science" thrown around by "audiophiles" sometimes drives me nuts!
Some people obviously like the "sound" of omni-directional speakers - but what they are liking is a form of increased phase and time alignment distortion from having the original signal bouncing around the listening area. There used to be all sorts of electronic "spatializers", or "spacial enhancement" boxes in the 70's and 80's that did exactly what omni's do - introduce controlled phase and time distortion. Why? - because some people found it pleasant or fun. "Distortion", which is simply a deviation from the original source's output, isn't necessarily unpleasant but let's be real about what it is.
1. Your ears are not able to discern the broad "shape" of the "front" of a soundwave. A change in the air pressure in your ear canal moves your eardrum either in or out, which in turn vibrates some bones, which then vibrate fluid in your inner ear, and finally - at the back of your inner ear that is converted to an electrical impulse. In addition, the "cleanest" wave you can incite will come from a smooth "point" source.
2. The idea that somehow bouncing recorded output around at random is more accurate than directing back, from a "point source", what stereo microphones have already picked up is nonsense and/or marketing hype. You only have two ears - and they do exactly the same thing as microphones. You don't need 6 or 8 ears to receive spatial information. The most accurate thing a speaker can do is create in reverse EXACTLY what occured at the diaphragm of the microphone. It's extremely delicate information, and the more it bounces around the room, the more of it is lost, period! Of course it's not perfect reproduction - everything ELSE a speaker does may sound good to some people and bad to others, but it's "distortion". The spatial information of the original sounds' environment is ALREADY IN THE SIGNAL - you don't need to somehow alter or re-recreate it to make it more "real".
3. I have owned many types and brands of speakers, sometimes 8 or 10 pairs at once, and have a very nice A/B testing set-up where I can swap from one pair to another using only a foot switch. I personally prefer minimum baffle speakers***. But for example, even in A/B testing the Dahlquist DQ20i (minimum baffle) against the Alon V (which is an extremely similar design but has a 90% OPEN baffle mid and tweet) it is becomes apparent how much distortion the rear waves from the Alon's sets up. By itself, it sounds "open" and "spacious" - in A/B it sounds open, spacious, and MUDDY!
*** Of course, minimum baffle design is also a trade-off of where you like your distortion, too. Instead of output reflecting immediately off the baffle, there'll be more "escaping" to reflect from surrounding walls, etc. Apparently, my ears prefer that. |
Some early Ohm/Walsh's I believe, were omni. They decided to un-omni the consumer line (starting with the Ohm/Walsh 2, I think) to make room placement easier simply by placing a baffle inside the mesh canister which absorbed/deflected the "rear" output from the Walsh cone. |
Hi AudioKinesis - IMHO the reverberant energy in a hall is either a fortunate or unfortunate attribute of that hall - depending on one's tastes and location. I would call it distortion, as compared to the piano in an anechoic chamber. Except that, to get philosophical about it, certain genres, forms, and specific pieces of music were developed/composed with certain assumptions about the acoustical properties of the places or media where they were likely to be heard - especially with regards to classical music, e.g. Russian church choral music wouldn't sound right in a jazz club.
But my point is that the best a speaker can do is re-create what you would have heard at the point where you were sitting - and a microphone has ALREADY picked up all those reflections, time-delayed, and out-of-phase sounds.
As far as the ear's diaphragm is concerned, there are never "sounds arriving at different times in different ways" - there is only one complex waveform which already IS the net sum of all those primary and secondary elements hitting you at any point in time. (That's why there is only one groove necessary in a record). This is what the microphone records, and is all that needs to be re-amplified. Adding omni-directional characteristics to speakers is simply like changing the acoustics of the hall that the piano was recorded in. Some will like it, others won't - but it's not what was there in the first place.
I'm not a purist in the sense of maintaining the original if something else is more pleasing or fun, but personally, I'd rather have a Yamaha DSP that gives all sorts of acoustic playback options - including the option of turning it off. And I'm a big fan of the DBX 5bx dynamic range expander (which actually DOES restore the signal to more like the original.)
I just think that if you want to alter the signal that's on that CD or LP, having your speakers bouncing sound off the walls and ceiling is really not the best way do it. |
Eldartford - The fact that an instrument is larger than a cone driver doesn't mean the driver can't reproduce the sound that we, as humans with ears, would hear if we were sitting a reasonable distance in front of it. The "planar speaker" argument which keeps popping up here completely misinterprets the mechanics of both recording, wave theory, and human perception.
1. Our ears, like the microphone, also only sample a small portion of the "wavefront". All we need, and in fact, WANT, to do is accurately reproduce that little portion of the wave. The whole point is that the microphone's diaphragm takes the place of our ear. It's "sample" is about the same size as an eardrum. Therefore, any driver larger than the mic's diaphragm is capable (theoretically) of fully reproducing the same sounds the mic heard. The only issues governed by driver size are volume and distortion - (the larger the driver the louder it can play a certain frequency range, but the more prone it is to distortion at a given level of power input.)
Otherwise headphones wouldn't work. They're much smaller than a cello. The reason planar headphones sound good has nothing to do with the size of the wavefront or the drivers, and the reason some people like planars has nothing to do with the "shape" of the original or reproduced wave.
2. All a speaker can be asked to do is accurately regenerate the information that was recorded (sampled) by the microphone. Making the driver bigger or smaller doesn't add any data that was lost in the size of the "sampling", if there really were. Even assuming that a cello created a strange, planar wavefront*** (see #3. below) that had different properties along it's "face", a planar speaker can't reproduce the waveform that was created by the soundboard - it can only reproduce the sample that was picked up by the mic. It brings to that sample certain sonic attributes of its own - but not more of the cello's attributes than a cone driver of equal quality.
3. There is no "cello-soundboard-shaped wavefront" that zooms by the listener. If there were, by the time it got to the back of a symphony hall, all you would be hearing would be the vibration of a 1000ths of an inch specific section of the soundboard. Someone sitting in the seat 5 over from you would hear a different concerto than you. Waves don't work that way.
If you drop a brick in a pond - are the ripples that emanate outward rectangular? Yes and no - for a very short distance they are, then very quickly they're not.
Why - because the wave and it's medium constantly interact with each other. This rapidly "smooths" the sound to a uniform waveform (at reasonably equal angles from the source). Within a few feet the wave IS the same as if it came from a point source. 20 feet out in the pond you would not be able to tell me whether I dropped a brick or a bowling ball by lookint at an ear-sized sample of the rings emanating from the center.
Have a good weekend all. |
I'm not disagreeing that many might find the Shahinian sound pleasant. But it is just that, a "sound". I, personally would rather hear (usually) the piece as it was recorded.
Don't take this as directed personally but: One thing people don't seem to get - the acoustics of the hall are ALREADY IN THE RECORDING - as recorded (if it's done right)! You may enjoy adding your own reverberation, but if you play back a CD recorded in St. Paul's Cathedral on a great system in an anechoic chamber, it's going to sound more like it was recorded IN ST. PAUL'S CATHEDRAL, than if you play it back in a large tiled bathroom.
The reason people like to sing in the shower is because the reverb from the tiles makes them sound "better". That doesn't mean they're ready for the Met. So if you like adding reflections from your walls that's perfectly fine - I have no prejudice about what people like - but it's not a more accurate reproduction of what was recorded. |
Dear Newbee - I wasn't really serious about the DSP. But I listen only to vinyl and the DBX (even a 3bx) is IMHO essential. I really have pretty good ears and have tried to find a fault with this thing and can't. It's the only add-on I have. The sound is soooo much improved. I haven't had anyone listen who wasn't floored by it. It's takes compressed analog (like almost every record ever made), and restores the dynamic range and punch that it had - there's no going back once you hear it. There's nothing magic about compression that can't be reversed with a proper algortihm.
I know many vinyl/audio snobs would have a kneejerk negative reaction to such a device, but then they've just bought a $5,000 tonearm to listen to highly compressed source material with numerous clicks and pops? It ain't that accurate to begin with.
Damned if you don't and damned if you do I guess....
Any Audiogoners in the SF Bay area who'd like to stop by hear it are welcome. You'll be on Ebay buying one within hours.
OK - I really have to get out of here this time... |
Hi all again - I'll be heading out for the weekend so this is my last post for now:
re: Sean - I started a new thread on DBX expanders so as not to drag this one OT with that stuff.
re: Audiokinesis - What you say about mic location is very true, and it has a huge impact on the success of a recording as far as I'm concerned - but that's a whole other topic, too.
The anechoic chamber or overdamped room probably sounds dull because of some or all of these reasons:
-It's not what we're used to.
-You can actually hear how IMPERFECT even a great recording played back on high quality equipment really is compared to the original!
-Room generated Reverb is fun.
-We expect it to be dull - the placebo effect.
-In a properly set-up room we are actually relying on/using wall interactions to cancel out the fact that your right ear is hearing the left channel output, and your left ear is hearing the Right channel, etc. - which dramatically reduces the stereo effect. (It might be interesting to hear a perfectly set up Carver Sonic Holography unit in anechoic chamber. Don't worry, I wouldn't use one at home.)
So, yes, I do hold that all interactions are colorations of what was recorded. But indeed we all may want those colorations because they sound better than not having them by bringing back some of that "liveliness" which was lost in the reproduction process.
re: Holzhauer - I don't have anything at all against omni-directional speakers if that is what somebody likes. My only "objection" when I started posting here was really the quasi-science which is so profusely expounded by the speaker builders/marketers and then absorbed as fact by audiophiles.
I have owned 3 pairs of Ohm/Walsh (with and without the dampening material inside the can) and have had friends with planars (quad/maggie/X-static/ML), which I enjoy but wouldn't want for myself.
As came up in Audiokinesis post - I suppose we do need and enjoy some amount of room interaction, but anyway I look at it - the more interaction the more "distortion" from the original. My experience (for my particular taste) is that the amount thrown off by an omni- is too much, in too many ways, to control properly so that I get the sound that I enjoy, which is very precise imaging with very minimal coloration. I'm going nuts right now just trying to tame the rear wave from a pair of Alon V's to direct and reduce the rear wall bounce.
I haven't heard Shahinians and am always open. |
Hi - (I'm not sure where the DBX post has ended up. I think it will probably appear in Misc. Audio.)
Until 6 months ago I had 8 pairs of speakers here - but I'm in a one bedroom apartment, and my new wife just moved in! I just gave my Ohm/Walsh 2's to a friend because they were too "big". Now it's tame little Sequerra Pyramids in the 2nd system.
On the other hand, she promises to buy me a pair of Avantgarde Duo's when we eventually move and have the space for them! |
GMA Continuum 3's - Just listened to a pair that's for sale near Modesto, CA which I probably should buy - but I'll have to go back again. My initial impressions, without being able to hear vinyl which is pretty much all I listen to (I brought a TT but we hadn't realized that the owner had no phono section) -
Overall, really great speakers. Some of the best I've heard.
Dynamic and immediate is an understatement.
My main concern is they seemed a bit bright in the upper-mids for my tastes, as many of the modern designs seem to be. For example, the female chorus in Steely Dan's Babylon Sisters didn't have that sweet, smooth, harmonic sound that they should - they were somewhat etched and stinging especially as volume went up. (Don't worry - I don't listen to a lot of Steely Dan, but there's a couple of tracks I use for evelauation purposes...)
The Mid-mids and Low-mids and Bass were SPECTACULAR, as was imaging and coherence. I'm not generally a fan of ported bass designs and this one is not only ported - but ported UP directly into the open-baffle rear wave of the midrange driver. An odd decision designwise. Do you think Roy would let me just shove a dark gray towel in there?
When I get a chance to go back, which is about a 2 hour drive, I'll bring a tube pre-amp (Granite Audio) with a phono section and see if the vinyl/tube combo tames the upper-mids.
All in all, though, when I got home I was very happy to be back with my trusty DQ-20i's. They lack serious "punch" but they are so neutral and so listenable, they've proven hard to give up. (Just spent 4 days intensively A/B'ing against Alon V Mk. 2's and I like the DQ's better - mostly because the Alons pass too much rear wave out to bounce off the back wall.) Also - believe it or not - the DQ tweeter is better.
BTW - If I don't buy evetually those GMA's somebody else out there ought to - at $4000 they're a steal compared to the new price, and these really are like new (+ already broken in!). |
re: the GMA Continuums - I think it's probably the associated equipment, or the room itself - or maybe just my ears - but I figure I'll go back with some tube stuff and vinyl and try again (if they don't sell first). But I'll tell you, it's been really hard to match the smoothness and neutrality of the DQ's - very underrated speakers because they're not the newest whizzbang technology. They have a bit of a dip in the low-mids (probably where the crossover point is) but I may just upgrade the caps and tweeters and live happily for another year or two, until I move into a big enough apartment to fit Avantgarde Duo's. |
Binaural Recording Baby! - If you want to feel like you are there! So how come nobody does it? Jazz At The Pawnshop, clearly one of the most successful recordings of all time, was done with a binaural setup. From the Proprius website:
"Palmcrantz rigged the main microphone pair facing the stage, about two metres above the floor. These microphones were Neumann U47 cardioids, spaced 15-20 cm and inclined at an angle of 110-135 degrees.
This ORTF stereo technique - named after the French radio which introduced this simplified dummy head technique at the beginning of the sixties - was, according to Palmcrantz, the best method for optimal stereo effect and spatiality.
- Real stereo effect can only be achieved by placing the microphones in a similar way to the disposition of the ears.
Such a pair stood in front of the stage at Stampen and another pair was placed to the right of the stage, facing the audience in order to recreate the right "live" feeling. Some auxiliary supporting microphones were also necessary. One microphone was placed next to the grand piano standing on the right-hand side of the platform with its lid open, and Palmcrantz hung two cardioid Neumann KM56s over the drums on the left side of the stage. The bass, standing in the middle, and connected to a little combo amplifier on a chair, was supported by a Neumann M49, also in omnidirectional mode. The microphone was placed in such a way that it caught sound both from the instrument and from the amplifier's loudspeaker. "
I had a feeling this thread would get around to this end of things eventually. One of the biggest problems for us trying to reproduce music at home is inconsistent recording technique/methodology.
If all recordings were done this way I don't think you'd want/need Omni speakers to give you that feeling of presence. |
