Measure Mixer Output

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doncolga
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Measure Mixer Output

#1 Post by doncolga »

Hey all,

My mixer output seems to be low to me. How would I measure that to see if it's doing what it's supposed to be?

Thanks!

Donny
Donny Collins
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Two 18" Tuba 30's 3012 LF
Two 26" Tuba 30's Lab 12
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BrentEvans
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Re: Measure Mixer Output

#2 Post by BrentEvans »

Use the same method you user to measure amps. 1k sine into a channel, gain it up until the channel is just below clip, turn up outputs until just below clip, measure pins 12-3 AC voltage. 1.7VAC would reference +4db over unity gain. More is fine, very much less than that would mean low output.
99% of the time, things that aren't already being done aren't being done because they don't work. The other 1% is split evenly between fools and geniuses.

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J_Dunavin
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Re: Measure Mixer Output

#3 Post by J_Dunavin »

If you had an oscilloscope then you could actually see where it clips too. That would be the bees knees! I barrowed one from work to set up my system! Turns out that the red LED really does mean it's clipping. HU who knew?
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doncolga
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Re: Measure Mixer Output

#4 Post by doncolga »

OK...here's what I'm observing...

I'm sending a 1 K tone, the channel is soloed and channel fader and master faders are in what I believe are the unity gain positions (it's near the top and labeled "0" with a bolded horizontal line at that mark.) The multimeter is reading 1.26 -1.6 to keep the mixer lit up to +4. Clipping starts are 5.07 volts. What does all that mean?

Thanks!
Donny Collins
Built:
Two 18" Tuba 30's 3012 LF
Two 26" Tuba 30's Lab 12
Two OmniTop 12's DL 2512 (Melded Array)
Presonus Studio One DAW
Harrison Consoles MixBus 32C DAW

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BrentEvans
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Re: Measure Mixer Output

#5 Post by BrentEvans »

It means your mixer is doing exactly what it's supposed to do. 5v clip is quite common.

Circling back... why do you feel your mixer output is low?
99% of the time, things that aren't already being done aren't being done because they don't work. The other 1% is split evenly between fools and geniuses.

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doncolga
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Re: Measure Mixer Output

#6 Post by doncolga »

BrentEvans wrote:It means your mixer is doing exactly what it's supposed to do. 5v clip is quite common.
Very cool Brent. Thanks for the affirmation.
Donny Collins
Built:
Two 18" Tuba 30's 3012 LF
Two 26" Tuba 30's Lab 12
Two OmniTop 12's DL 2512 (Melded Array)
Presonus Studio One DAW
Harrison Consoles MixBus 32C DAW

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BrentEvans
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Re: Measure Mixer Output

#7 Post by BrentEvans »

Heh... you must have missed my edit.

What makes you think the mixer has low output? There must be something you've recognized as a potential symptom.
99% of the time, things that aren't already being done aren't being done because they don't work. The other 1% is split evenly between fools and geniuses.

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doncolga
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Re: Measure Mixer Output

#8 Post by doncolga »

BrentEvans wrote:It means your mixer is doing exactly what it's supposed to do. 5v clip is quite common.

Circling back... why do you feel your mixer output is low?
I think maybe I just need to run my amps with more sensitivity. Inputs going in are hot enough, channel faders are in the unity gain area. I usually have the main faders way up in the unity gain area too...it just feels like the mixer outs are not very hot when the faders are that high. The board meters around +4 or so at that point.
Donny Collins
Built:
Two 18" Tuba 30's 3012 LF
Two 26" Tuba 30's Lab 12
Two OmniTop 12's DL 2512 (Melded Array)
Presonus Studio One DAW
Harrison Consoles MixBus 32C DAW

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BrentEvans
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Re: Measure Mixer Output

#9 Post by BrentEvans »

doncolga wrote: I think maybe I just need to run my amps with more sensitivity. Inputs going in are hot enough, channel faders are in the unity gain area. I usually have the main faders way up in the unity gain area too...it just feels like the mixer outs are not very hot when the faders are that high. The board meters around +4 or so at that point.
That's probably the answer. Gain structure can be a booger. Don't forget to reset your limiters if you didn't do it with amp gain maxed out to begin with.
99% of the time, things that aren't already being done aren't being done because they don't work. The other 1% is split evenly between fools and geniuses.

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doncolga
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Re: Measure Mixer Output

#10 Post by doncolga »

BrentEvans wrote:
doncolga wrote: I think maybe I just need to run my amps with more sensitivity. Inputs going in are hot enough, channel faders are in the unity gain area. I usually have the main faders way up in the unity gain area too...it just feels like the mixer outs are not very hot when the faders are that high. The board meters around +4 or so at that point.
That's probably the answer. Gain structure can be a booger. Don't forget to reset your limiters if you didn't do it with amp gain maxed out to begin with.
Yes...I set it with the sub amp wide open. Thank again man!
Donny Collins
Built:
Two 18" Tuba 30's 3012 LF
Two 26" Tuba 30's Lab 12
Two OmniTop 12's DL 2512 (Melded Array)
Presonus Studio One DAW
Harrison Consoles MixBus 32C DAW

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