POLL: How do you connect your stereo oscilloscope?

Topics regarding professional record cutting.

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How does mono look on your scope?

1. Upper right to lower left
1
25%
2. Upper left to lower right
0
No votes
3. Horizontal
0
No votes
4. Vertical
3
75%
 
Total votes: 4

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blacknwhite
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POLL: How do you connect your stereo oscilloscope?

Post: # 10877Unread post blacknwhite
Tue Oct 12, 2010 8:41 am

POLL: For those of you who have an oscilloscope connected to your cutting lathe to visualize how much out-of-phase material there is, etc. etc., OR for those who use a "virtual" scope in the digital pre-processing stages:

How is it oriented?:

Image

Trying to determine if there is one currently-agreed-upon "standard" / "traditional" way of doing it, or if everyone does it differently.

Besides responding to the poll, if you could also post a message saying which choice you made in the poll and whether you are using a software-based scope visualization or an actual separate oscilloscope, and if that oscilloscope is built-in to a traditional disc mastering console or rack component (i.e. one made by Neumann, Haeco, Nevee, {Scully?}, etc.) Also, any other cutter scopes you have seen.

I already got one response from Nickou for #4 vertical, but also having seen folks use #3 horizontal - Thanks!,

- Bob
Nickou wrote:Hi bob ,

vertical is the mono , and , so .. ,horizontal the out of phase

but ..
a lot of cutting room plug it to have the in phase horizontal , like the information cutted on the disk
cheers

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leo gonzalez
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oscilloscope phase

Post: # 10879Unread post leo gonzalez
Tue Oct 12, 2010 10:32 am

bob, this depends completely on the oscilloscope model you are using.

on a classical tektronik kind scope it would be number 1.

but on a newer dk audio meter it would be number 4. these are nice cause the lines are also labeled on the screen, unlike the oldies.

i dont know if there is an agreed convention or standard, just depends on the meter and which axis -line is your 0 degree line, from there you can deduct where's your 180.

i think yann is basing his answer from a more modern phase scope convention like the dk type which emulates the position of the listener in front of a 45-45 speaker placement.

I think a better tool is a good correlation meter. possibly better than a phase-scope.

best,
leo

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blacknwhite
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Re: oscilloscope phase

Post: # 10882Unread post blacknwhite
Tue Oct 12, 2010 1:14 pm

leo gonzalez wrote:just depends on the meter and which axis -line is your 0 degree line, from there you can deduct where's your 180.
Cool, thanks for the input Leo - I suspected that there may no longer be a single "standard" orientation...

So I guess we;'re back to the question... how is Mono oriented on Lathe Troll forum members' scopes, and how have you seen it on other folks' scopes?.

Also, I'd be interested to know if there was ever a "standard" / common orientation for the old pro Neumann & Scully lathes & associated consoles, back during the height of vinyl cutting...

- Bob

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Nickou
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Post: # 10883Unread post Nickou
Tue Oct 12, 2010 2:32 pm

the old neumann transfert desk were using NTP vectorscope , and 4 is what you see for mono info

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cohearent
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Post: # 11580Unread post cohearent
Fri Nov 26, 2010 3:21 pm

If you feed left to X and right to Y on any conventional oscilloscope a Mono signal will produce #1. Disk cutters like to see lateral and vertical modulation. So, if the scope has a round tube it is a simple matter to rotate the tube 45 degrees clockwise in its mount. Since most scopes have square tubes (or are software based) it is necessary to matrix the left and right signals to sum an difference exactly like an M-S mic matrix. It requires a couple dual-secondary-winding transformers or 4 opamps.
On every NTP I have seen, (and I'm talking dozens) #3 would be mono. #4 would be "out of phase", actually reversed polarity.
The problem is which channel is which? The disk cutting convention used by Neumann/NTP would be #1 for left channel. This would match the actual stylus motion as seen looking at the face of the cutterhead. Unfortunately for me, the first console I worked on for 5 years used #1 for Right channel. I got so used to that, that I use that setup for my system, so I admit being backwards to convention.
Kevin Gray

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