More DL Meter Magic

[WK154]

I decided to look at the channel strip a little closer, my misfortune. The manual states that when you pan hard right or hard left that the channels output will increase by 3dB and measured with both meter and scope it does. Unfortunately the master fader (L & R) meter on the side that increases by 3dB goes nowhere and of course the other channel goes to infinity (off) as it should. So now you have 3dB more than indicated by the meter and if you're close to the feedback limit it's feedback time. It's called "equal loudness" a new version of Mackie feedback. I'm well aware most mixers compensate for pan but to not indicate that on the meter is stupidity. Why bother dropping the other channel meter to infinity ?

Continued: use 2 channels and the meter moves even if one channel is muted. I'm going for coffee. I was in the dead zone (transition near 0 were meter movement is negligible) moving away from that level shows what I would have expected a 3 dB change. Mackie fix this junk!!

[Wynnd]

This is nit-picking on a mixer that doesn't cost more than $5K.  My take anyway.  If it were perfect on this aspect alone, I doubt if a typical user would notice it at all.  I surely wouldn't have.  3db?  Not worth worrying about in my mind.  I doubt if any of my mixers were that accurate at any point in my life.  (Let alone having a vu meter that went that small.)    That said, a friend's band was using a DL1608 as the mixer for a five person rock band.  3 vocals, 2 guitars, drums....  It was loud, but that's never the mixer's fault.  (Powered speakers, monitors and subs.)   It was fine for the type of music.  There really isn't a reason to play that loud.  They would have sounded better at lower volume and people might have actually wandered onto the dance floor.  My take anyway. 

[WK154]

What happened to pride and quality workmanship? Especially if it takes not a dime to do it right. You need to make that $5K down to $1K cause I would be upset if My Yamaha or X32 or the M32 would provide me with this kind of information. 3dB is noticeable by normal hearing a lot of musicians probably need 10dB, that's double the loudness in psycho-acoustics. In Voice Record Pro the VU meter almost moves a point and that's significant to those using meters. I grant you that for a lot of uses of the DL a 1/4" line stating " Use Your Ears for Volume indication" would be sufficient. and not waste all that screen real estate. I agree with you on loud music it's not very romantic.

[Jkowtko]

I don't understand how an increase in the input channel's feed would not be picked up by the LR meter?  Doesn't the LR meter just measure it's input signal?

[WK154]

If you have a steady sound source +-0.2 dB you can observe it yourself. Just set the input channel meter and fader to 0 and the master fader to 0 and you will find 1st a loss of 3 dB in the chain indicated by the output. This would be using a sine wave for the signal. You then simply pan hard left or hard right on the channel and watch the output meter. If you can detect any movement it would be about 1 dB (magnifying glass time). If you meter the output L or R you will see a 3 dBu change. Mackie has a long history of messing with meters. With meters done correctly you would see the change. The L & R meter is the last thing in the digital output chain.

[WK154]

Actually an even easier test is to again find a stable sound source and set the MF to 0 along with the meter then move the Fader. Does the meter track the fader moves, NO. Does the output track the fader moves, YES. I'd say there is something wrong with this picture and would welcome an explanation.

[Jkowtko]

Hmmm ... it still seems very unlikely that the LR meter would know anything about the source of the individual signals coming over the bus and the input channel fader/pan settings.  Are you implying that it is?

There is also a 3db attenuation on each input channel before summing onto the bus, correct?  Is that relevant?

Have you tried this with stereo channels, and multiple channels active?

[WK154]

Let's not complicate the test it's a single channel of input. Next stop is the L & R outputs. No eq's or any other processing involved other than channel pan. The output should reflect the adjustments to the channel. First you need to get the simple settings correct before venturing into stereo or multiple channels.

[Jkowtko]

Not complicate the test, but determine what variables affect the behavior.   

If this works properly on a stereo channel but not a mono channel, that would be good to know. 

How about two mono channels panned the same way?  Do you get 6db discrepancy instead of 3db?

This might help you to understand logically where the problem is occurring.

etc ...

[WK154]

I already know were the problem lies and it's been defined since the old Mackie forum.  But don't let me stop you from exploring all the permutations and combinations. Hint nonlinear meter display is the problem. Remember this is about meters and it caught me off guard. If you want to explore the bus and other aspects of the DL go for it.
For those interested in the numbers the meter values from -12 to +2 dB, a 14 dB range, in fact covers a range of -20 dBu to +10 dBu of output, a 30 dB range. That's about a 1:2 ratio as opposed to 1:1 as it should be. The output above +2 dBu is 8-10 dB higher than the meter indicates and below -12 dB is 10-12 dB lower than the meter indicates.
For the bus summing for each doubling of input channels (ie. 1,2,4,8,16) the output increases by 6 dBu for a total of 24 dBu. This is for in sync sine waves of equal value with a crest factor of 3 dB not music which has a crest factor of about 8-20 dB.