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Topic: Mackie 1200 VLZ Issue |
James Quillian
From:
San Antonio, Texas, USA
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Posted 2 Mar 2021 12:05 pm |
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I am not getting a signal when plugging an instrument into the inputs in the section market in read. The inputs to the left work fine.
Is there a certain way these inputs must be used? It is probably something I am not doing correctly.
Of course it may be a problem with the unit itself. I need to find out if it is.
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_________________
Curbside Jimmy's New Act
https://www.youtube.com/watch?v=XlzieFLE5no |
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Howard Parker
From:
Maryland
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Posted 2 Mar 2021 1:11 pm
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Are those the settings you were using because you have the gains turned down for CH5-CH12. I can't tell if you also might have the channels muted (button below the "Pan" knobs).
h
_________________
Howard Parker
03\' Carter D-10
70\'s Dekley D-10
52\' Fender Custom
Many guitars by Paul Beard
Listowner Resoguit-L |
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James Quillian
From:
San Antonio, Texas, USA
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Posted 2 Mar 2021 1:48 pm
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That is not actually my mixer in the image. I just used it because it is exactly the same.
The channels to the left work fine. Nothing has been muted and volume is set.
| Howard Parker wrote: |
Are those the settings you were using because you have the gains turned down for CH5-CH12. I can't tell if you also might have the channels muted (button below the "Pan" knobs).
h |
_________________
Curbside Jimmy's New Act
https://www.youtube.com/watch?v=XlzieFLE5no |
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Howard Parker
From:
Maryland
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Posted 2 Mar 2021 2:21 pm
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fwiw
Inputs 1-4 are "instrument Level" 5-12 are "Line Level" and might not have sufficient gain for a "raw" intsrument feed. |
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Dave Mudgett
From:
Central Pennsylvania and Gallatin, Tennessee
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Posted 2 Mar 2021 2:45 pm
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The inputs in the section outlined in red are line-level inputs. They are expecting a signal on the general order of 1-1.5 volts peak-to-peak, which is taken as a 0 to +4 dBV reference for other signal levels.
Typical instrument or mic level inputs are roughly 20-30 db less than line level, or more like 30-100 miillivolts, with passive mics usually being the weaker signal. This is a factor of around 10-30 smaller. So it's not surprising you don't get much output if you just plug a guitar into a true line-level input without any trim pot to increase the gain.
If you want to be sure those line inputs are working correctly, plug in something with a larger signal output. Maybe a rack effect that has a line level out, maybe the output of a clean boost with a gain factor of around 10 or more. I have an old (late 70s-early 80s) MXR Noise Gate / Line Drive that does this pretty well. But anything that will give you around a 20dB (10x) clean boost. I suggest clean boost because you want to know if the preamps are cleanly amplifying. |
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James Quillian
From:
San Antonio, Texas, USA
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Posted 2 Mar 2021 5:33 pm
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| Dave Mudgett wrote: |
The inputs in the section outlined in red are line-level inputs. They are expecting a signal on the general order of 1-1.5 volts peak-to-peak, which is taken as a 0 to +4 dBV reference for other signal levels.
Typical instrument or mic level inputs are roughly 20-30 db less than line level, or more like 30-100 miillivolts, with passive mics usually being the weaker signal. This is a factor of around 10-30 smaller. So it's not surprising you don't get much output if you just plug a guitar into a true line-level input without any trim pot to increase the gain.
If you want to be sure those line inputs are working correctly, plug in something with a larger signal output. Maybe a rack effect that has a line level out, maybe the output of a clean boost with a gain factor of around 10 or more. I have an old (late 70s-early 80s) MXR Noise Gate / Line Drive that does this pretty well. But anything that will give you around a 20dB (10x) clean boost. I suggest clean boost because you want to know if the preamps are cleanly amplifying. |
I plugged a stereo receiver into it and it lit up. So that worked.
_________________
Curbside Jimmy's New Act
https://www.youtube.com/watch?v=XlzieFLE5no |
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Howard Parker
From:
Maryland
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Posted 2 Mar 2021 5:37 pm
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Excellent. Sounds like it is functioning as designed.
h |
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