Vectorscope or equivalent

[kozikowski]

With respect to this answer:

http://forum.audacityteam.org/viewtopic ... 93#p232193

The short, definitive answer is View > VectorScope and make sure you have a fan or blob of audio and not a straight line.

If you have a straight, bright line, that means the show is mono and you are missing some of the sound from your vinyl.

Koz

[steve]

Does "jellyfish.ny" fit the bill? http://forum.audacityteam.org/viewtopic ... 68#p160968

[kozikowski]

Didn't we discuss this in another thread? Jellyfish.ny returns a text number and is easily fooled by a mono show out of stereo balance. It may also give significantly misleading results for a mono show out of stereo phase.
Koz

[steve]

Didn't we discuss this in another thread?

The only discussion that I recall is here: http://forum.audacityteam.org/viewtopic ... 40&t=61484

"Jellyfish.ny" is a very simple plug-in. It simply gives a figure for the waveform similarity. Where a user just wants to know "is this recording 2 channel mono", Jellyfish.ny will provide the (correct) answer. It is extremely easy to use and has that one feature only.

As Gale wrote: "Robert's Stereo Toolkit has extensive information about stereo correlation."

I take it that Koz wants a real "Vectorscope" with a real jellyfish.

[kozikowski]

take it that Koz wants a real "Vectorscope" with a real jellyfish.

Well, yes I do. It tells you a lot of quality information just by glancing at it.

It may not have to be in motion like the classic scope.

Stop > Drag-select a portion of the show > Display as Jellyfish. That will reveal direction, amplitude and phase without having to muck about in motion graphics for three different computer platforms.

Remembering that a proper Jellyfish will also reveal Mono phase problems. "How come the top is one straight line but the bottom is all similar smeary loops?"

Koz

[steve]

Remembering that a proper Jellyfish will also reveal Mono phase problems. "How come the top is one straight line but the bottom is all similar smeary loops?"

How's that? What are "the top one" and "the bottom one"?

[Robert J. H.]

Remembering that a proper Jellyfish will also reveal Mono phase problems. "How come the top is one straight line but the bottom is all similar smeary loops?"

How's that?

Good question.
I think a normal vector scope for a monaural sound shows a straight, diagonal line from the left lower to the right upper corner. A 180 ° shifted version goes from the left upper corner to the right lower one.
The "stereo bursts" deviate from those lines, but the general picture should be the same.
By the way, is the jellyfish.ny anywhere downloadable?

[steve]

By the way, is the jellyfish.ny anywhere downloadable?

Yes, but you'll probably be disappointed it is only a very simple tool. Here's a direct link: http://forum.audacityteam.org/download/file.php?id=4238

I think a normal vector scope for a monaural sound shows a straight, diagonal line from the left lower to the right upper corner. A 180 ° shifted version goes from the left upper corner to the right lower one.

The one that I use shows a vertical line for mono, which tilts diagonally according to the pan position. It also has a bar graph at the bottom that goes from -1 to +1 to indicate the relative phase of one channel to the other. -1 means out of phase (-180 degrees), +1 means in phase (0 degrees). The width of the blob (if not a straight line) shows the amount of variation between the channels. Basically it is an oscilloscope where the left channel controls one diagonal and the right channel controls the other. A horizontal line shows that the audio is mono but 180 degrees out of phase.

[Robert J. H.]

Thanks Steve, I am not authorized though.

[steve]

Sorry Robert, I didn't even look at where the download was. Here it is:

jellyfish.ny

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