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The 'Jam' test.

L5730

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#1
Hello everyone,
Some time ago, mid 1990's, a chap in a HiFi and music Instrument store suggested that there is a simple test to quickly rule out an audio setup. He didn't give it a name, but I have, and am calling it the 'Jam' test.

1. Take Michael Jackson's "Dangerous" album, with the first track titled "Jam".
2. Play it over the first few seconds.

If it doesn't sound like a window has just been smashed, something is up. A lot of gear makes it sound like a wine glass smashing on a tiled kitchen floor, reverberations aside. It should have some mass and not tinkle.

I guess this depends if this album is remastered (or silently mastered differently) and if the proper sonic intent has been preserved.

My near field monitors are borderline wine glass, somewhere between the two. It's OK I know they have flaws, I work around them.
These new Takstar Pro 82 headphones are definitely giving window smash sound.
Little JBL PC speakers also give the impression of a window smash, albeit a bit lower fidelity of course.

Might be interesting to give it a try.
 

Tks

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#2
I'm totally lost here. What does it mean "rule out an audio setup". Rule out what aspect of it? It's competence, it's relevance, it's fidelity?

Am I supposed to hear my window smashing after I'm done listening, or is the smack sound supposed to sound like a window "smashing" (I presume you mean shattering)?

Is the Amazon music version a "proper master"? How would I know which.

Also the whole window and wine glass smashing on a tiled floor. Windows smashing or shattering sound utterly different to a wine glass shattering, not only that, various types of windows in various settings sound different (as evidenced by any movie you watch of a window being blown up or something through through it).

Lastly, what does it mean "it should have some mass and not tinkle" what is a mass sound? All I can imagine is bass? Tinkle I suppose is on the extreme end of treble?

Also, lets put aside all these questions. Why would this be a "simple test" remotely conclusive of any sort of fidelity test to surmise whether a sound system has validity? But worst of all, how does he know what that sound in the song should even sound like. Is he speaking from a true-to-life representation/emulation of the sound that was being played at the studio, or is he talking about the fidelity of whatever at all was even recorded at said studio? Because without being at the studio itself and hearing the sound itself independent of the recording, I don't understand how he's deriving validity in the premise of his proposition. What I'm saying is, why would I even accept the first portion of his condition.. why would I accept that sound ought sound like that? What is that in virtue of?
 

L5730

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#3
Smashing > Shattering, yes, my lack of choosing the correct word. Thanks for bringing that point up.

The situation/setting in which a glass (we assume it's glass) window shatters can change it's sonic character. Of course it can. A huge open warehouse with concrete floors, tall ceilings and lots more glass around is going to sound different to a small window in a small lounge being "put through".
A wine glass shattering on carpet, tiled floor, concrete floor, laminate floor or whatever else, as well as the acoustic space will change the sound too.

What the actual master that you have to listen to actually sounds like is a big question. Sure, a very valid point.
What was the origin of the sound source -was it a synthesised sound? Was it captured in a dry room? Was the mastering monitoring 'off' and so over compensated somehow?

The shattering window certainly doesn't seem to have much of any spacial cues. It's very brief.

OK, so we'll assume it's a perfect, or near as perfect recording of a real pain of glass being shattered with a softwood mallet, and recording in an anechoic chamber. Hardly real world. I suppose the point being that if that's what it is, it should sound like that.

Hey, look, take this with as much salt pinching as you like. I am not suggesting anything. I don't mean offence, and I am just suggesting trying something that might be fun, or not. It might cause one to search more into how this sound was made, it might not.


Something I find funny/strange, a lot of orchestra musicians don't listen to high end audio setups or even well measuring audio setups. They listen on cheapy naff little micro HiFis and stuff, that really obviously sound lo-fi. They know that a recording is never going to sound like the real experience, so seem not to invest in equipment. They may have lots of reasons really, but this seems one that I've come across.
People into their audio equipment cam sometimes bang on endlessly about the depth and detail and hearing into the music, discerning little intricacies in the orchestra etc. Seems odd to me that a musician wouldn't want the same experience - maybe it's more about performance than nitpicky after the fact. I am odd topic here, so...
 

L5730

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#4

This is definitely different to the album version of the track. That ball bouncing after it has gone through the window - that extra thump doesn't happen on the album track, but there is a lumpy sound really shortly after the 'window' shatters. Two different recordings of something shattering? It's already turning into a bit of a mess!
 

Blumlein 88

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#5
Pretty good rendition of glass breaking listening on my phone. Not using headphones either. Just built in phone speakers.
 

solderdude

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#8
I know about the glass breaking in private investigations.
On the proper speaker/headphones it is extremely 'real'
 

Tks

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#9
OK, so we'll assume it's a perfect, or near as perfect recording of a real pain of glass being shattered with a softwood mallet, and recording in an anechoic chamber. Hardly real world. I suppose the point being that if that's what it is, it should sound like that.

Hey, look, take this with as much salt pinching as you like. I am not suggesting anything. I don't mean offense, and I am just suggesting trying something that might be fun, or not. It might cause one to search more into how this sound was made, it might not.
You offend no one, it's a adequate and fine discussion, so no worries on that end.

As for the ideal condition, I wouldn't even remotely know what that would even sound like as I've never been in such a situation. Not even in a non-controlled setting let alone an anechoic chamber.

But regardless of even all this, my other incomprehension stems from the other stuff I mentioned. Again, I hope to reciprocate the same sentiments and hope you're not taking offense to what I'm saying, but there was more than half of my inquirey that went ignored. For example the mentioning of mass and tinkle which is something I have no idea what it could even mean in ANY context, let alone this one.
 

L5730

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#10
Hey we're all good. Text vs. face-to-face, or even audible interaction.

Mass vs. tinkle.
In a nutshell, just saying that a large window pane is going to sound 'weighty'. Dropping a wine glass on the floor and listening to it shatter is going to sound thin and sparkly/tinkly in comparison. I'm struggling for a better way to explain this.

As human beings we of course learn to identify sounds, even if the sound is not actually the real thing but a recording or close enough synthesised sound. Something just sound fake no matter what, others sound quite convincing.

Hmm ... wow, smashing!
 

RayDunzl

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#11
If it doesn't sound like a window has just been smashed, something is up. A lot of gear makes it sound like a wine glass smashing on a tiled kitchen floor, reverberations aside.
Listening on the "computer speakers", I get what sounds like a modified handclap, the glass breaking and falling onto a surface, with a single drum strike (kick or tom, not as low as subsequent kicks) embedded in that toward the end.

1573424791268.png


Listening with the big rig, there might be two more low level drum hits in the main breaking glass area for emphasis.


It should have some mass and not tinkle.

I find it to have mass and tinkle.
 

Tks

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#12
Okay, I somewhat understand, but here's the thing. The wine glass falling can never have "mass" as much as a glass window, but that's only because due to the literal mass of each compared to one another.

Regardless, even with the understanding demonstrated. How does that relate to the song my Michael Jackson, like how would I know what that actually is supposed to sound like? I don't even know exactly what id making the sound, how it sounded live to the people there, or how it's supposed to sound played back from a recording (aside from the actual playback we hear from the song itself).

My main perplexity is how does one grant validity to the folks who told you "this is how you can tell you got a good audio system very quickly". Like, why would I trust that to be a valid litmus test considering they themselves don't actually know what "it's supposed to sound" whatever that even means?
 

pozz

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#13
Okay, I somewhat understand, but here's the thing. The wine glass falling can never have "mass" as much as a glass window, but that's only because due to the literal mass of each compared to one another.

Regardless, even with the understanding demonstrated. How does that relate to the song my Michael Jackson, like how would I know what that actually is supposed to sound like? I don't even know exactly what id making the sound, how it sounded live to the people there, or how it's supposed to sound played back from a recording (aside from the actual playback we hear from the song itself).

My main perplexity is how does one grant validity to the folks who told you "this is how you can tell you got a good audio system very quickly". Like, why would I trust that to be a valid litmus test considering they themselves don't actually know what "it's supposed to sound" whatever that even means?
It's a subjective test and an interesting way to guage a system, though I wouldn't take it too seriously for the reasons you mentioned. A foley effect is usually manufactured from several sounds in any case so it's better not to mentally "search" for the correct reference.

I found that, with better speakers, older movie foleys sometimes sound ridiculous and certain effect work (reverb, delays) in music tends to stand out garishly. Can't think of any examples at the moment, but that's been a repeat experience.
 

restorer-john

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#14
My main perplexity is how does one grant validity to the folks who told you "this is how you can tell you got a good audio system very quickly". Like, why would I trust that to be a valid litmus test considering they themselves don't actually know what "it's supposed to sound" whatever that even means?
This was my experience, back in the same day (1990s) we are talking about, working in a real HiFi store:

When you work in a HiFi store and have access to literally tons of gear, you quickly distill down to a few discs or tracks that highlight the differences between a natural sounding array of components and not. All day you can try anything you want, play whatever you want in any of the listening rooms. You can re-arrange the room, the systems, the furniture, unpack new stuff, pack away other stuff. Roll in any speakers you like.

Whether MJ's Jam glass breaking is a super good recording or not, doesn't really matter. It just becomes a common reference you can use. I used different tracks myself for my own comparisons, and other guys had their own special tracks that worked for them.

You have discs/tracks that will sell anything to anyone, ones that highlight detail, bass, top end, whatever, and you use them all. You get to the point where you can tell in a second or two if a system works together or not. This is because you have so many component combinations available at the touch of the comparator's buttons, the bad combinations are immediately obvious.

Speaker/amplifier combinations and interactions are the biggest misunderstood part of HiFi in my opinion. That is where the system either works or it doesn't. And unless you have a lot of speakers, a lot of amplifiers and the ability to instantly select any combination, all this talk of amplifiers all sounding alike to one another, is just that- uninformed talk.
 

RayDunzl

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#15
My main perplexity is how does one grant validity to the folks who told you "this is how you can tell you got a good audio system very quickly".
Do you need to?

Try "Right on, bro!"

See if that works.

I like to use "Uh-huh" - which, with its various inflections, can provide a range of meaningful responses.

Here's a fairly neutral one, though maybe with a slightly positive tone.

And remember, practice makes perfect!


Advanced or otherwise specialized lesson here...
 
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Tks

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#16
It's a subjective test and an interesting way to guage a system, though I wouldn't take it too seriously for the reasons you mentioned. A foley effect is usually manufactured from several sounds in any case so it's better not to mentally "search" for the correct reference.

I found that, with better speakers, older movie foleys sometimes sound ridiculous and certain effect work (reverb, delays) in music tends to stand out garishly. Can't think of any examples at the moment, but that's been a repeat experience.
But see that's the thing, even in a subjective sense, I am at full loss with this many variables being logically inconsistent, what predictive value, or what value in virtue of being able to come to any sort of rational conclusion could be had with the approach proposed.

I try my best not to flat out say "I simply do not understand how any portions of this test are even logically feasible and to what end". I try to explain how I come to such machinations.

Now you propose there is something there, but even that - what is it that is being gauged here? Like lets say those reverb, delays are noticeable in 100% of cases of (for example) all movies before the 1960's. What value are we extracting here from this revelatory property of the speaker that we couldn't simply by looking at some of it's specifications/measurements for example? Or is this simply just another method of coming to the same conclusions as a measurement that demonstrates a speaker is of high quality/fidelity?

I swear I'm not trying to be pedantic, or terse or anything, and I really do apologize to anyone reading this that is irritated. I am just truly lost as to the value of this approach in almost any facet that isn't based out of a presupposition of some sort of imagination fueled scenario devoid of value placements with coherence as it relates to true to life observation.
 

Blumlein 88

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#17
snippage....

Speaker/amplifier combinations and interactions are the biggest misunderstood part of HiFi in my opinion. That is where the system either works or it doesn't. And unless you have a lot of speakers, a lot of amplifiers and the ability to instantly select any combination, all this talk of amplifiers all sounding alike to one another, is just that- uninformed talk.
I certainly have the same experience here. And agree it is largely misunderstood. Going back to those Swedish AES series amp tests. I don't know the total number they tested, but being rather rigorous they only ran across two that came really close to being straightwire with gain, and only one that passed muster of blind testing. And their most revealing test signal was a metronome sound. Wished I knew more about the details about that test signal.
 
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