Can Loudspeakers Accurately Reproduce The Sound Of Real Instruments...and Do You Care?

[Cosmik]

Stereo is not a hologram.

I've played with a real hologram.

It's spooky.

Is stereo not spooky? I think it is. A sound apparently emerging from thin air is pretty spooky.

 

[Zog]

I don't see that as a given. We only have two ears, and so two channels is all you really need. What comes over the channels and how they reach your ears is the question.

Twenty seven channels is not much better than two channels compared to the infinite number of channels that perfection implies. And then twenty seven channels seems a bit 'blunderbuss' in comparison to the two-channel system that I, and some others, are often fascinated by.

My suspicion is that surround sound is a ho-hum 'ambience button' while stereo is a remarkably exquisite 'hologram'. Of course you can have the hologram and the ambience button too, I suppose.

Almost all live listening is done by listening to performers in front of you. The last thing I want when listening to a Beethoven symphony is to hear the Cellos coming from the Right Surround speaker.

My other objection to 'Surround' sound is more prosaic. Money. I would rather pay for two good floorstanders than split my dosh between 5.1 speakers, not to mention the extra amplification.

 

[Blumlein 88]

Is stereo not spooky? I think it is. A sound apparently emerging from thin air is pretty spooky.

It still isn't a hologram. If it were we could walk up to the musicians and walk around amongst them aurally speaking.

I do agree a solid near believable image form thin air is spooky. We have simply gotten used to it.

Stereo could almost be like stereo pictures. Think Viewmaster reels.

 

[MRC01]

Stereo, when recorded with certain 2-mic methods like Blumlein or ORTF, can create an audio image that is so lifelike it feels 3-D and while it's not literally a holograph, I understand why people call the effect holographic. These kinds of recordings are rare, but it shows what stereo is capable of. The effect is similar to a binaural recording on headphones.

 

[RayDunzl]

Is stereo not spooky? I think it is. A sound apparently emerging from thin air is pretty spooky.

It is not holographic.

 

[MRC01]

... I'd played the acoustic guitar track on my friend's mega-buck system and though it was clear as a bell and I could hear super clean differentiation between all the guitar strings....it just didn't "sound" like an acoustic guitar I know. The color was "off" it didn't sound real. ...

This is what I experienced the first time I listened to planar headphones a few years ago. They were HE-500. The clarity & resolution was excellent. Listening to an ensemble of about 15 instruments playing together, I could hear each and every one. I could tell there was a bassoon, 3 string players, etc. But the bassoon didn't sound like a real bassoon. It was like a cartoon caricature of a bassoon. Same with the violins and other instruments.

I believe the term for this is "voicing", at least that's what I mean by it. It's distinct from other attributes like clarity, dynamics, transient response, etc. Most of my music listening is natural acoustic instruments and good voicing is one of the most important attributes for me to fully enjoy the illusion.

 

[MattHooper]

It is not holographic.

Well..that's a bit pedantic

I see the term 'holographic' generally being used among audiophiles to describe soundstaging/imaging that isn't just "3D" as "3D" can offer conjure the type of layering of flat images one can find in some 3D films, but rather has a sense of roundness and depth almost as if you could, like a hologram, walk around the images.

I get that quite often from the MBL speakers

 

[Kal Rubinson]

Almost all live listening is done by listening to performers in front of you. The last thing I want when listening to a Beethoven symphony is to hear the Cellos coming from the Right Surround speaker.

Agreed. Not a problem. The vast majority of classical recordings are made with the proper perspective with mostly ambiance in the right (and left) surround.

 

[Duke]

... loudspeakers with the least audible contributions - the most neutral ones - get the highest scores and these have consistently been the ones with the fewest measurable flaws. Flattish and smooth frequency responses indicate an absence of resonances. It is not mysterious.

The section I have enjoyed the most (thus far) in the Third Edition of your Book has probably been your very personal and in-depth analysis of what the bipolar Mirage M1 speakers did so well in your home listening room back in the day.

In post 142 above, Matt Hooper says this about his MBLs:

... when I switched in my MBL radialstrahler 121 omni speakers... WOW...sounds through the MBLs just took on a rainbow-like sense of timbral variation... Everything just sounded that much more real."

It seems to me that the common denominators between your experience with the Mirages and Matt's experience with the MBLs have to do with the reverberant field being spectrally-correct and well-energized, as these two designs seem to excel in these areas. Do you find these two characteristics to be good predictors of enjoyable timbre (assuming the speakers are also relatively free from distracting resonances)? Or is one more important than the other? (If so, I would guess that the spectral correctness of the reverberant field matters the most.)

I realize that I am over-simplifying by not dividing up the "reverberant field" into first reflections and later reflections, but the bipolar Mirages and the omnidirectional-in-the-horizontal-plane MBLs probably do a better job than most with the spectral balance of both the early and the late reflections.

Thanks!

 

[Cosmik]

It is not holographic.

When I say 'hologram', I mean that it is a phenomenon that emerges when two sources interfere. They're not interfering? Well both speakers are heard at both ears, and the difference between what is heard at the ears creates the three-dimensional image.

You can't get up and walk around the image, but you can move position and still have a plausible image. Sitting in more-or-less the correct position you can turn your head while listening to Blumlein stereo and the image stays stable i.e. it doesn't do unnatural 'head tracking' but appears to be emanating from stable source positions ahead of you.

It can be shown that it gives a 'true' image i.e. that based on cross-correlation of what is arriving at the ears, the interference replicates the apparent positions of the sources at the original recording.

That this works at all, doesn't need calibrating to your head and ears, doesn't need your head to be in a vice, and doesn't seem to upset the timbres within the recording is quite something, I think. It's so simple in practice and such an old technology that its resemblance to the slickest high technology created by Ray Kurzweil or whomever is often forgotten, I think.

 

[Cosmik]

I don't think discussion of stereo is off topic btw. The original question about speakers replicating the sound of instruments can be interpreted as asking whether a single dedicated speaker can replicate the sound of a single instrument, like a speaker-based fairground organ. It's an interesting idea and would be an interesting toy to play with.

But to be practical, and for the system to be unconstrained in what it records and plays back, one speaker effectively has to reproduce multiple instruments and their acoustics. A single mono speaker must make all the sources appear to emanate from the same position which is unnatural - the speaker may get the timbres right, but it is not replicating the sound of the instruments in a way that is plausible. Introduce that second speaker, and suddenly the instruments and their acoustics are separated from each other in a way that could be natural. It's not just a minor difference but a fundamental one.

 

[Blumlein 88]

Holograms are recordings of scenes illuminated by a coherent light source. Stereo isn't the soundfield of something illuminated by coherent sound sources.. In this sense a hologram of Sonic's would only reproduce the room. It would fail at recording other sources of sounds.

 

[Cosmik]

Everyone seems very keen to tell me what a literal hologram is, but they're missing that I put 'hologram' in quotation marks. I know what I meant and have explained why, and to what extent, I think the term 'hologram' is a useful analogy.

 

[Blumlein 88]

Everyone seems very keen to tell me what a literal hologram is, but they're missing that I put 'hologram' in quotation marks. I know what I meant and have explained why, and to what extent, I think the term 'hologram' is a useful analogy.

I don't think it is useful as an analogy. It would be more like a stereogram in photos, and only then if recorded with no more than 2 microphones. Which is very rare in music available to us. So its usefulness is limited even so.

 

[Cosmik]

I don't think it is useful as an analogy. It would be more like a stereogram in photos, and only then if recorded with no more than 2 microphones. Which is very rare in music available to us. So its usefulness is limited even so.

But what about the notion of interference? A stereogram directs a discrete image to each eye, while stereo feeds each speaker to both ears and from that, the image - as if by magic - emerges. With speakers it's not just a stereogram. It may 'look' like one, but how it was created is much more interesting.

With Blumlein stereo there was no literal time difference recorded, but the interference produces the correct time-of-arrival difference at the ears. If that's not a fascinating thing, I don't know what is.

 

[Blumlein 88]

But what about the notion of interference? A stereogram directs a discrete image to each eye, while stereo feeds each speaker to both ears and from that, the image - as if by magic - emerges. With speakers it's not just a stereogram. It may 'look' like one, but how it was created is much more interesting.

With Blumlein stereo there was no literal time difference recorded, but the interference produces the correct time-of-arrival difference at the ears. If that's not a fascinating thing, I don't know what is.

Its fascinating and ingenious how Blumlein stereo worked and that he understood why. The interference sets up a soundfield. But it isn't a soundfield replica of the one where the recording took place. In the right spot it is a perceptual result something like that original event.

 

[MRC01]

The way ORTF works seems to be more intuitive: the mics are about as far apart as our ears. Both give an excellent stereo image. While I've recorded both ways, I've never compared them back-to-back.

 

[DDF]

Have you listened to "Drums and Bells" by Chris Dutz?

Do you mean this with Brad Dutz and Chris Wabish?
https://positive-feedback.com/reviews/music-reviews/tony-minasian-drums-bells/
Not on Spotify or Tidal unfortunately, but the link has a sample.

It has extreme dynamic range which will contribute mightily to the realism you hear.

The engineer used to make his own speakers and second hand reviews say that he used a purposely resonant cabinet design. https://forum.audiogon.com/discussions/thin-walled-speakers-tonian-musical-affairs-etc

 

[Blumlein 88]

The way ORTF works seems to be more intuitive: the mics are about as far apart as our ears. Both give an excellent stereo image. While I've recorded both ways, I've never compared them back-to-back.

I've mentioned some careful tests were done, and Blumlein (if the speakers are at 90 degrees) give the most accurate portrayal upon playback. If speakers are 60 degrees (much more common) Blumlein is still usually best or 2nd best.

In my limited experience and tests, I don't much like coincident X-Y cards. You get some stereo, but it seems to be amorphous imaging. Theoretically M-S would give the same results. I like M-S better though some of it is being able to do some post manipulation of aiming. It does however share a less distinct imaging and seems blurry or not very good around the edges on each side.

ORTF or DIN (I've used DIN more) gives better results. j.j. says it gives a larger sweet spot and better imaging. I agree on the imaging, not sure I've experienced the larger sweet spot. It makes sense, you get the built in creation of timing differences from spaced speakers, plus some actual timing difference spacing the microphone. So it is easy to see how moving your head a bit before things fall apart would result.

I very much like the seeming see thru transparency of omnis. But they have issues too. I like using them with a Jecklin disk. I think you get almost a hole in the middle imaging somewhat like a pair of omni's too far apart though not quite that much of a hole. The center seems softly defined. The result is very believable, but also compared to the real scene inaccurate. I've done tests and it compresses the outer edges, and is indistinct in the middle because it spreads out the angles. I've wondered if an third center omni mixed into both channels (or maybe a card) could help with that. But with the imaging compression of the outer angles I've not bothered so far.

As someone who occasionally does this as a hobby, I'd like to have two or three or at most four microphones. Mixing processing multi-miked recordings is too much work. But most people seem to like the multi-miked results much better. Being able to throw up two mikes and get a good result where you don't do much further is much nicer. But that limits opportunities.

I actually am more interested in doing some surround recording. But no one has a need or desire for that. Oddly, there are lots of carefully done tests about how to mike surround for music. Even more oddly they come to very contradictory conclusions in regards to accuracy and usefulness.

 

[MRC01]

Do you mean this with Brad Dutz and Chris Wabish?
https://positive-feedback.com/reviews/music-reviews/tony-minasian-drums-bells/
Not on Spotify or Tidal unfortunately, but the link has a sample.

It has extreme dynamic range which will contribute mightily to the realism you hear.
...

Yes that's the one; I misquoted the musician names.
It has great dynamics, yet also has excellent voicing, incredible bass, fantastic transient response. One of the most lifelike recordings I have ever heard.
Tony Miniasan's other recordings are also great. But that one really is something special.