Genelec on audio science

[svart-hvitt]

At the same time it has to be noted that audio forums also think that short lengths of mains cable are not a trivial problem.

@Cosmik , your remark on mains cables and audiophiles reminded me of how Markus Kahelin answered this question just recently on Genelec forum:

«The mains power cable has no effect on the sound quality of the Genelec product. as long as the cable is safe to use and has sufficient length to reach the power socket».

In other words: Audiophile should be very concerned about mains cable lengths. If the cable is too short, there’s no sound!



This is the the Genelec answer in its entirety, which I think is a classic to illustrate the crash between audiophile superstition and audio science:

«Hi!

The mains power cable has no effect on the sound quality of the Genelec product. as long as the cable is safe to use and has sufficient length to reach the power socket. The overall length of the mains cable from the powerplant to your house and wiring inside the house is in total much more than the last few meters before the device. All Genelec products have a power supply built in to the product, that has been designed to supply the needed operating voltages for the electronics and to eliminate any mains power related interferences. We do advice all products with a 3-pin mains power connection to be connected to a 3-pins safety grounded mains outlet. even this is more important for the overall specified electric safety requirements than the acoustic output quality. You can use your Genelec system with the original power cable and enjoy the best possible sound quality!

Best Regards, Markus
Genelec Support Team»
Source: https://www.community.genelec.com/forum/-/message_boards/view_message/995038#_19_message_995038

 

[Blumlein 88]

Multi-channel surround: an analogy..?

Perhaps what I was going on about yesterday could be described as follows:
Suppose you have a 3D TV. By whatever means are used, separate images are directed to the eyes, thus giving you an illusion of a 3D scene before you. However, it is limited to the scene only being in front of you. Some technologies require active glasses, some passive, and some use optical prism arrays.

Adding a third 'channel' would make no sense because you only have two eyes. It would not be a statement of the obvious to say that three or more channels were better than two - as has been said about multi-channel audio.

You could don a VR headset, which would allow you to synthesise an all-round 3D scene - although not necessarily a 'recorded' one. There would be a difference between being able to turn your head and look up and down, and actually being able to get up and walk about. Also, VR headsets are uncomfortable.

But here, I think, is where the temptation towards 'gimmick' comes in... If you were to place loads of ordinary 2D TV sets around the room, 90% of people would think they were in a genuine 'immersive' video environment. This is the same as those VR headset videos that are not 3D, but allow you to turn your head and look around as though surrounded by a large spherical TV set. Most people don't even care that it isn't 3D.

Not only that, but such a scheme would enable you to say "Hey! Look we can even get up and walk about and it still makes sense. This truly is a holodeck". But it wouldn't be. Most people probably wouldn't care, though.

This is what I am thinking is going on with much of this multi-channel audio (even just the idea of adding a centre channel). It is certainly 'surround' and 'multi-channel' and kind of 'immersive', but it isn't '3D'. Whereas plain common or garden stereo is 3D. But maybe the distinction between the two isn't important and no one cares.

There may be ways to 'project' a 3D scene at the listener, using '2D' transducers and head tracking - I suppose BACCH et al. are on this path. It would be great if it worked, and didn't have any side effects and felt real when you turned your head rather than just 'headphones without headphones'.

But in the meantime, I think that plain stereo with speakers performs quite a trick: it creates a genuine 3D image, but it also blends with the real room acoustics so that the listeners' own speech, shuffling of the feet, etc. feel quite consistent with the music. It creates an illusion of 3D, yet 'makes sense' even when turning your head. It seems natural to 'face the music' as in 99% of musical performance situations.

Given limited resources, should a person concentrate on getting good stereo or comprehensive multi-channel? I would say the former. If resources are not limited, then sure, go for good stereo and multi-channel - but don't use a centre channel when not listening to surround sound: it constitutes the meaningless 'third channel' that you don't need if your stereo setup works well.

Your analogy would only be accurate for headphone listeners. Stereo doesn't have the separated presentation to each ear that 3d glasses have when listening over speakers.

 

[Cosmik]

Your analogy would only be accurate for headphone listeners. Stereo doesn't have the separated presentation to each ear that 3d glasses have when listening over speakers.

It 'half works'; almost like the best of both worlds. There is cross-channel leakage of course, but the brain seems to absorb it, and the whole thing works remarkably well anyway. It isn't 'headphones without headphones' (which I'm not sure I'd want anyway) but has a seemingly logical response to head movement.

At the same time, the image for a good recording doesn't just look '2D' (like a large TV viewed from a distance), but more like '3D' with depth and the ability to 'look around and through' the scene . It doesn't hang together as you move through a large distance necessarily, but it starts to work again as soon as you stop moving.

I am not under any illusion it is a literal portrayal of the real recording venue, but at least it is a very compelling 'view' of an imaginary venue, IMO.

 

[Fitzcaraldo215]

Or it can be thought of as a creative space rather than a "gimmick" -- just as many classic rock albums use stereo creatively or installations use multiple speakers for the construction of sound architectures.



I have a few of those SACDs and there is one I definitely prefer in stereo (because the centre sounds distorted): https://www.discogs.com/Mahler-Maur...ymphony-The-Song-Of-The-Earth/release/7660895

But isn't the 3-channel replay of those recordings a happy accident (perhaps even a "gimmick")? The centre channel was originally a separate microphone positioned to make a concurrent mono-compatible recording and wasn't really intended to be heard together with the stereo microphone tracks. So for decades there was no thought of replaying them as 3-channels until domestic 5.1 surround introduced a centre speaker.

I believe that, before there was industry agreement on a cutting/playback standard for 2-channel on LP, there were thoughts of 3-channel tape as a distribution medium. That did not progress very far, and the industry, after much squabbling, finally agreed on the 2-channel LP. It was then and only then that "stereo" came to be synonomous with 2-channel. In prior usage and experiments back to the 30's, "stereo" often meant 3-channel.

Early recordings by RCA, Mercury, Columbia, etc. in 3-channel may have been hedging their bets as to the outcome of those industry squabbles, which persisted for awhile. I have at least one Reiner/Chicago recording in 3-channel dating from 1954. The stereo LP appeared in '58. When the path was clear and well defined for the 2-channel LP, some, especially Mercury, continued with 3-channel recording, judiciously mixing the center into L and R, as they also did with their pre-'58 recordings for LP stereo release.

There are a few old issues of Audio and High Fidelity magazines floating around on the web that may provide some insights.

But, yes, it may be fortuitous that today we have access to some of those old recordings in 3-channel along with their 2-channel counterparts on the same SACD. To me, they provide listening credence to some of the advantages of discrete Mch recording and playback, though just in the frontal soundstage.

 

[Fitzcaraldo215]

It 'half works'; almost like the best of both worlds. There is cross-channel leakage of course, but the brain seems to absorb it, and the whole thing works remarkably well anyway. It isn't 'headphones without headphones' (which I'm not sure I'd want anyway) but has a seemingly logical response to head movement.

At the same time, the image for a good recording doesn't just look '2D' (like a large TV viewed from a distance), but more like '3D' with depth and the ability to 'look around and through' the scene . It doesn't hang together as you move through a large distance necessarily, but it starts to work again as soon as you stop moving.

I am not under any illusion it is a literal portrayal of the real recording venue, but at least it is a very compelling 'view' of an imaginary venue, IMO.

Yes, of course, stereo has a phantom sense of perceived frontal image depth. Even mono does to a much lesser degree. Renaissance oil paintings on 2D surfaces do too. Mch does not eliminate eliminate that. Actually, I think it improves on it for a number of reasons. But, listen and compare yourself to reach your own conclusion.

 

[amirm]

Cars are easy. The room and the speakers are well known. So are the listeners' positions.

Cars are actually difficult because they are small spaces and hence the transition frequencies are much higher than home listening rooms. This means the "problem area" (of frequency spectrum) is much larger.

The other problem is getting good sound to all the listeners. Having it work for just the driver would make an awful experience for the passenger for example.

 

[amirm]

And oh, there is also the challenge of space and weight. Automakers like to give as little of that to people designing car audio for them.

 

[NorthSky]

I went to a small venue last week, a jazz band was playing.
The sound was coming from everywhere; the stage, the side walls, the rear wall, bouncing from the floor and ceiling. It had all type of reverberations delayed by different time intervals. On the dancing floor it was more intimate and direct and less aggressive and more coherent and you were more here, there with the musicians, and they were more with you too on the dancing floor.

There were few people sitting on stools @ the bar made of exotic wood, and they look like jazz people...with many facial jazz expressions and liberate by their drinks and the music playing and the people dancing and all that jazz. They added to the decor and atmosphere. ...Visually, as a point of second reference.

The place wasn't acoustically treated, it was a very simple normal venue built in the late 1800s with brick walls. The bricks were looking old and had experience of time and history. The ceiling was approximately fifteen feet tall with pipes (black) running across.

The musicians (five of them) were separated by no more than twelve feet, from one extreme to the other.

There were no musicians on the side and rear, only upfront. Still, the sound was holographic, 3D, and encircling you all around.

 

[svart-hvitt]

GENELEC EXPERIENCE CENTRE, LONDON

Interested people could try multichannel and immersive formats at the Genelec Experience Centre in Fitzrovia, London.

Nice people there.

The centre shows what may be possible in non-perfect rooms, as this is not a geometrically perfect place where they have 1 meter thick bass traps, a room-in-the-room etc. So it’s a more «realistic» room, I believe.

My experience tells me that immersive and surround must be experienced, not «talked». And the Genelec room excels compared to some «private rooms» I’ve heard. Especially the level of detail was very good.

https://www.genelec.com/genelec-and-hhb-group-unveil-worlds-first-genelec-experience-centre

 

[NorthSky]

That looks like a Dolby Atmos recording/monitoring studio.

 

[svart-hvitt]

That looks like a Dolby Atmos recording/monitoring studio.

So what surprised me when I was there, was how similar the 8351as sounded in stereo in that room compared to my own room (which has no acoustical treatment at all).

 

[Fitzcaraldo215]

Taking the suggestion from an earlier post, I have summarized some of my experience with Mch music in this new thread:

https://audiosciencereview.com/foru...-for-music-standards-setup-thoughts-etc.3295/

 

[pirad]

Cars are actually difficult because they are small spaces and hence the transition frequencies are much higher than home listening rooms. This means the "problem area" (of frequency spectrum) is much larger.

The other problem is getting good sound to all the listeners. Having it work for just the driver would make an awful experience for the passenger for example.

Perhaps I should have written “easier”. True, they are not easy, and can be pricey too. Naim, Burmester, B&O, B&W, Levinson... I am familiar only with B&W in my wife’s Volvo and it sounds better than many people’s home hifis. It has some 20 speakers and a sub system built into the car’s subframe. Driver, All and Rear listening positions . One of the DSP programs is Gothenburg Concert Hall.

 

[svart-hvitt]

Perhaps I should have written “easier”. True, they are not easy, and can be pricey too. Naim, Burmester, B&O, B&W, Levinson... I am familiar only with B&W in my wife’s Volvo and it sounds better than many people’s home hifis. It has some 20 speakers and a sub system built into the car’s subframe. One of the DSP programs is Gothenburg Concert Hall.

If car audio were «easy», why would Samsung buy Harman?

 

[Fitzcaraldo215]

Car audio presents many specific difficulties. But, I have found it has improved by leaps and bounds over the years. One advantage is that it can be engineered and tested for a specific car interior, unlike the problems in engineering for a typical, but with widely generalized assumptions, home listening environment.

It may have been our old familiar whipping boy Bose who was one of the pioneers in thoroughly engineering solutions for specific cars. If true, hats off to them.

However, at best, cars can never deliver, due to their sonic environment, the sound quality of a well set up home system.

 

[Guermantes]

Your analogy would only be accurate for headphone listeners. Stereo doesn't have the separated presentation to each ear that 3d glasses have when listening over speakers.

I agree, the equivalent to 3D glasses would probably be binaural recordings on headphones.

I am not under any illusion it is a literal portrayal of the real recording venue, but at least it is a very compelling 'view' of an imaginary venue, IMO.

"A map is not the territory."

 

[Speedskater]

How about Hafler Hookup? Simple cabling extracts ambience from stereo and directs it to rear speakers. It saves money and marriages!

The Hafler system never worked well with vinyl. Much much of the record noise was not correlated, it ended up on the rear channels and was rather loud. Never got back to trying the Hafler system with CD's.

 

[Frank Dernie]

Car audio presents many specific difficulties. But, I have found it has improved by leaps and bounds over the years. One advantage is that it can be engineered and tested for a specific car interior, unlike the problems in engineering for a typical, but with widely generalized assumptions, home listening environment.

It may have been our old familiar whipping boy Bose who was one of the pioneers in thoroughly engineering solutions for specific cars. If true, hats off to them.

However, at best, cars can never deliver, due to their sonic environment, the sound quality of a well set up home system.

The problem with listening in a car is the noise. Even a quiet car has 70dB + background making it hopeless for classical music IMO. I tend to only bother with radio comedies and plays in my car, audio is usually switched off though.

 

[sergeauckland]

The problem with listening in a car is the noise. Even a quiet car has 70dB + background making it hopeless for classical music IMO. I tend to only bother with radio comedies and plays in my car, audio is usually switched off though.

That's all I listen to in the car. BBC Radio 4 or in France, radio plays downloaded to a USB stick. I leave music for when I get home.

S

 

[sergeauckland]

The Hafler system never worked well with vinyl. Much much of the record noise was not correlated, it ended up on the rear channels and was rather loud. Never got back to trying the Hafler system with CD's.

My SQ Quadraphonic system does that too. Clicks get moved to the back. Never got on with the Hafler system, but enjoy SQ, as a bit of fun.
S