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Old 5th August 2010, 01:48 AM   #5461
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Anyone else who has worked with Vu meters.
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Old 5th August 2010, 02:44 AM   #5462
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I use SPL meters in an attempt to set playback levels to record levels. As I understand them, VU meters measure decibels of the electrical signals (post electro-mechanical transducer in the case of recording, and pre, in the case of playback). VU meters are an aid to adjust record levels to prevent clipping (distortion).

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Using time-averaged levels, I'd like to find a means to correlate VU readings (or the like) to SPL readings. Of course, transducer response and room acoustics are large factors.


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Old 5th August 2010, 03:00 AM   #5463
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The Blowtorch does not have a power switch to avoid using signal switch/relay contacts for power on mute?


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Old 5th August 2010, 03:46 AM   #5464
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Hi John
I think I understand what you are implying here with your your Vu meter analogy and I agree with it entirely based on what I read at the TNT website.

However I have some experience with dither that is used in controlling servo-hydraulic machines for fatigue testing of materials. In this application it has the complete opposite effect. I wish I knew (it looks like I have something to read about now) exactly what the dither is doing to improve the response of the machine so I could comment further. However I could probably post some pictures to demonstrate how it improves the response. I don't know if this could be applied to audio in the same way it used in the servo hydraulic machine, but if it can, it definitely is worth looking into.
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Old 5th August 2010, 05:12 AM   #5465
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Quote:
Originally Posted by thanh1973 View Post
Hi John
I think I understand what you are implying here with your your Vu meter analogy and I agree with it entirely based on what I read at the TNT website.
What VU meter analogy was that? I don't see where John made any sort of analogy to a VU meter.

I made an impromptu "cognitive dissonance" meter in response to one of SY's posts and then John asked if anyone had ever seen or used a VU meter.

Where exactly was the analogy?

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Old 5th August 2010, 05:38 AM   #5466
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I read his mind. He hasn't shared the analogy yet.
I could be way off track with what he is trying to say here.

Last edited by Melon Head; 5th August 2010 at 05:45 AM.
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Old 5th August 2010, 05:42 AM   #5467
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Well, I noted that a continuous +3 on a Vu meter shows somebody not knowing how to make a proper recording. It looked silly to me, even though it meant something else. Nothing really hidden or that important.
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Old 5th August 2010, 05:52 AM   #5468
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Quote:
Originally Posted by thanh1973 View Post
I read his mind. He hasn't shared the analogy yet.
I could be way off track with what he is trying to say here.
I haven't seen any evidence that he's trying to say anything with regard to VU meters.

What TNT article are you referring to?

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Old 5th August 2010, 08:15 AM   #5469
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Dither article
That Dither Thing - [English]

Yes it works well if the intended signal is a sine wave.
What if the intended signal was a stepped sine wave as pictured would it still smooth the signal to a sine wave
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Old 5th August 2010, 08:28 AM   #5470
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It works with her voice, too.

Click the image to open in full size.

I can testify that said voice, while sinuous, is not a sine.
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