Live vs. Recorded - can you hear a difference?

Status
This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.
It's awesome that you're going to try such a comparison. It may not be a novelty, Either Duntech or Dunlavy used to do stuff like this (can't remember which).

I'll make the recordings available for download after the test.

That would be great too! How often do we get a chance to hear something like that.

I'm interested in the outcome. I think using a mono speaker is a good choice, though indeed an Omni speaker might have a better shot at it. Your speaker was designed to avoid reflections due to directivity while the "live show" will have them in a real room. Makes one wonder if you should have pré-recorded in that room.
 
it depends on what we want to get.
if you will want to get a fidelity recording,
this is the reverse of how we will should do.
Any sound produced in the anechoic chamber is not suitable for listen from our brain.
You will obtain a sound without the informations of the space around the instruments and,
again more important,
you will not have the space time informations, necessary, for links each one to the others the instruments and alls together for shape the live esecution.
and then when you listen you will add the informations produced from the room, informations not present in the live esecution.
Perhaps? are you trying to eliminate a source of disturbance?
The disturb are created from the conditions in which we listen the sound.
However i believe that your experiment will be much educational for your experience.
 
Unfortunately it's the crappy speakers in the photo. To be honest, I don't really think they're crappy (I actually think they're among the most accurate you'll find), but you're probably right in that an omnipole would be a better speaker for this particular job. That's because an omni has a dispersion pattern that's closer to that of the snare, the keys on a chain and the cello. To accurately reproduce spoken voice, a conventional 2-way box the size of a human head would probably be best.

We're trying to create the illusion of "here and now". The speakers we're using are better equipped to create an illusion of "there and then", which is an even more difficult one to pull off.

I agree about controlled directivity speakers being better at creating the illusion of "there and then" vs. omnis being better at creating the illusion of "here and now".

Also, given that 99.9% of the recordings are NOT anechoic, this is the reason why in my opinion and experience, omnis are a poor choice for the reproduction of conventional acoustic recordings.
 
it depends on what we want to get.
if you will want to get a fidelity recording,
this is the reverse of how we will should do.
Any sound produced in the anechoic chamber is not suitable for listen from our brain.
You will obtain a sound without the informations of the space around the instruments and,
again more important,
you will not have the space time informations, necessary, for links each one to the others the instruments and alls together for shape the live esecution.
and then when you listen you will add the informations produced from the room, informations not present in the live esecution.
Perhaps? are you trying to eliminate a source of disturbance?
The disturb are created from the conditions in which we listen the sound.
However i believe that your experiment will be much educational for your experience.

Not intending to sound snarky here, but I think that if you want to take part in forums like this, then you should work on improving your English. It's very hard to make out what you want to say.
 
Administrator
Joined 2004
Paid Member
Keyser. I'm surprised at the 1/10th dB levels, I don't remember finding it that critical, but do remember that it was touchy. No, not done at any audio show that I remember, just private demos among enthusiasts. The give-away for me, outside of level, is always a boxy sound. Speakers can so easily sound like boxes - often the problem is in the low midrange. Speaker that don't sound boxy often go a long way toward sounding real. It may be different for different people, but that was my main clue.

I find it surprising that so many people think this isn't possible, don't understand the test, think it's pointless or bring up issues that don't really matter. Maybe I've just worked with live sound and recordings for so long this test doesn't seem so complex to me. Many of the issues involved are not what most people imagine, maybe that's what leads them astray. You are already well down the road to understanding what' needed for a test like this. Have fun and best of luck!
 
First of all one has to know what one is doing. What is the stereo sound? How does this illusion work?

We need a theory.

For example David Moulton has a theory of how speakers in stereo work:



Sounds right BUT OTOH the first of a set of early reflections is not what a stereo mic records. So there is fundamental inconsistence between what the mic records and how the loudspeakers are perceived.

Anyone has a better theory?

I don't think he is saying that they are reproducing some recorded early reflections but that the brain interprets whatever is recorded AS early reflections, regardless of what has been recorded. Sounds like a kind of made-up theory *unless* there is some psycho-acoustic or nurological evidence pointing towards that.
 
Yes, and I think it's because people will be open to being fooled and how many will know what the live instrument sounds like anyway? Who are the listeners going to be?

Hmm... beware of people who consider themselves experienced in an area in sense-related studies like that. Beside everything else, they have their egos telling them that they should find it easy and then start looking for particular signs they believe will be most obvious based on a congnitive theory - i.e they will stop listening and only hear what they want to hear.

It's like our brains' naturally learned ability to recognise faces. Once you see a face in a random pattern of dots, it is very hard to un-see it... even though it doesn't exist.

Better often to have people with no expectation and to make simple judgement on their senses and not pre-concieved ideas.
 
I find it surprising that so many people think this isn't possible, don't understand the test, think it's pointless or bring up issues that don't really matter. Maybe I've just worked with live sound and recordings for so long this test doesn't seem so complex to me. Many of the issues involved are not what most people imagine, maybe that's what leads them astray. You are already well down the road to understanding what' needed for a test like this. Have fun and best of luck!

Maybe you are correct, if you've kind of done these comparisons simply in the course of life rather than set out as such.. A result that showed people couldn't reliably tell the difference would be fine and would require no further thought.

Any result where people *could* tell the difference, then requires some thought on whether it is the fault of the speaker not reproducing the sound well enough, or down to other factors that perhaps hadn't been considered, flaws in the whole set-up, recording technique etc etc ect

The latter result then renders the test a bit pointless unless one does their best to render the other factors insignificant. And perhaps that is what people are doing here - taking some time to think/talk the experiment through.

You'd have to counter everyone's points and say why they were not valid or not worth considering to really have a constructive analysis, if you felt so motivated :D
 
Administrator
Joined 2004
Paid Member
Well I don't know that I'd have to counter everyone's points, but it may be worth discussing a few, which the OP and I have both addressed. From reading the test I think it is well constructed and has a good chance of success.
Some points worth considering:
  • Recording technique. Much of this is taken care of by recording in an anechoic chamber. As explained, this eliminates any recorded acoustics which would be mixed and confused with the playback room acoustics. Recording in a well treated room with directional microphones is another way to this, but perhaps not as good. The distance of the mic(s) needs to be well chosen, and that is usually done thru trial and error. The idea is to make the recording sound like a cello that's playing in the playback room. Double acoustics can muddy the sound and be an easy clue.
  • Keep it simple. Recording a single instrument raises the chances of success, mostly because of mic technique and speaker placement on playback.
  • Playback level. This is critical, as has been discussed. A level that is not matched to the reference will still sound good, but is less likely to fool you than a tightly matched level. If the listener is not directly comparing real to recorded, then level matching is less critical. But level does remain important for a sense of realism.
  • Visual cues. One would hope for a blind test, but they aren't always needed. E.G. I've done a test were a string quartet was playing in one room, and it was piped live to speakers in another room down the hall. Listeners could go back and forth between the two to compare and criticize the reproduced sound - and that was useful.
  • Fooling people. As any magician knows, it's not too hard to trick people - if you set out to fool people, you usually can. Edison did it with his Diamond Disk (which is remarkably good) by training his singers to sound like the payback. :p That's not the goal here, this looks like a very honest test, not a trick.
 
I don't think he is saying that they are reproducing some recorded early reflections but that the brain interprets whatever is recorded AS early reflections, regardless of what has been recorded.

therefore I point to an inconstistence, more precisely not "whatever is recorded" but the speakers as sources in stereo reproduction

Sounds like a kind of made-up theory *unless* there is some psycho-acoustic or nurological evidence pointing towards that.

I don't think it's "made up". The analogy seems rather common sense.

Have You got a better theory?
 
Last edited:
No body records in an anechoic chamber for a reason, it dosnt sound right. It changes the tonality of the instrument by removing all but the direct sound. The sound emited from all other angles from the instrument, which will have a different harmonic spectrum than the direct sound will disappear.
 
Great recordings have an illustrious history. IMO, when you throw great musical artists together with great engineers, the results are astonishing. :D

These are old recordings put together with simple dual cardiod microphones and attention to avoiding overload which makes for distortion. Mostly done in the Concert Hall.

The first great choice you could look out for on CD is Frank Sinatra with the great Count Basie band. This is SO live. Possibly worked even better on Vinyl.

I also love Ella Fitzgerald and Louis Armstrong. Ooh YEAH! :cool:
 

Attachments

  • Frank Sinatra and Count Basie.jpg
    Frank Sinatra and Count Basie.jpg
    78.1 KB · Views: 186
Status
This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.