Skipping issue with diamond.

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crowesBR
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Skipping issue with diamond.

Post: # 43358Unread post crowesBR
Fri Jul 22, 2016 8:21 pm

Hi all.
Recently I was doing some cuts with diamond and I notice that some part of music have some skipping issue.

Not sure if is the depth of cut, too much volume, too much weight,... Also if I have less volume some weird echo appears on the beginning of the discs.

I'm using a Presto 6N with MyShank diamond and blanks.

Can you tell by looking at the grooves? See photos.

Thanks for any help.

Image

Image

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piaptk
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Re: Skipping issue with diamond.

Post: # 43360Unread post piaptk
Fri Jul 22, 2016 11:33 pm

You are cutting some really tight grooves. 224 lpi? They don't appear to be crossing though....
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crowesBR
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Re: Skipping issue with diamond.

Post: # 43361Unread post crowesBR
Fri Jul 22, 2016 11:43 pm

Yes. 224 lpi.
For some reason some parts of the track are skipping. Not sure why. Not crossing.

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piaptk
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Re: Skipping issue with diamond.

Post: # 43362Unread post piaptk
Fri Jul 22, 2016 11:44 pm

They appear deep enough. Same part of the audio every time?
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crowesBR
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Re: Skipping issue with diamond.

Post: # 43363Unread post crowesBR
Sat Jul 23, 2016 12:53 am

Yes. All the same.

Think that maybe I'm going to deep.

If I go down the volume like 10% starts getting a little echo on the first seconds when start cutting

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crowesBR
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Re: Skipping issue with diamond.

Post: # 43364Unread post crowesBR
Sat Jul 23, 2016 1:11 am

Few more pics.
How can I measure the groove width? Like 2-4 mil,... Any tools?
My scope didn't have any.

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Image

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crowesBR
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Re: Skipping issue with diamond.

Post: # 43369Unread post crowesBR
Sat Jul 23, 2016 5:50 pm

Ok looks like if I adjust the weight on my playback tonearm the skipping is not happening anymore.

If I have more that 0.5 than start skipping. Too much weight skip.

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Aussie0zborn
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Re: Skipping issue with diamond.

Post: # 43370Unread post Aussie0zborn
Sun Jul 24, 2016 7:06 am

The echo you hear is pre-groove echo and is caused by too much level when grooves are too close. The modulation is transferred to the previous groove. Your pre-echo would probably be worse if you were cutting into lacquer.

As you are cutting with a fixed pitch, this echo is probably occurring throughout the whole track but is masked by the level.

If you had automatic variable pitch, the pre-groove echo could almost be non-existent. Neumann lathes with an "ECHO" function allow you to open the pitch further by holding down the "ECHO" button. This is useful when a song starts with a loud percussive sound such a snare drum.

If its a problem, can you hand crank and increase the pitch a little at the start of each track?

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crowesBR
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Re: Skipping issue with diamond.

Post: # 43373Unread post crowesBR
Sun Jul 24, 2016 1:53 pm

Thanks
Yes
I'm using a fixed pitch.

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crowesBR
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Re: Skipping issue with diamond.

Post: # 43374Unread post crowesBR
Sun Jul 24, 2016 5:33 pm

Ok. I could fix that "echo" adjusting my levels.

Now I hear the vacuum in the background. :shock:

Damn.

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Aussie0zborn
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Re: Skipping issue with diamond.

Post: # 43376Unread post Aussie0zborn
Sun Jul 24, 2016 7:38 pm

Decreasing the pitch will solve that problem and allow you to cut at a higher level again.

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