kradcliffe
OK guys, Denon MCX8000
I pick a track with a beat. Autogain set to auto, ZeroDB set to default, no effects, gain pot set to zero and the channel LEDs are going in to the red. Doesn't look like the limiter is cutting in however I'm not keen on the track peaking so high. If I turn the gain pot higher then the limiter instantly cuts in.
If I set ZeroDB to -3 the LEDs go down a bit to mid orange, and if I set it to -6 they pretty much stay in the green, but of course the output volume is now far lower.
Are we saying here that in order to avoid hitting just below the limit threshhold we have to use a ZeroDB value as it doesn't seem right with everything on flat the top peak red LED is coming on all the time.
Am I understanding things correctly here?
I pick a track with a beat. Autogain set to auto, ZeroDB set to default, no effects, gain pot set to zero and the channel LEDs are going in to the red. Doesn't look like the limiter is cutting in however I'm not keen on the track peaking so high. If I turn the gain pot higher then the limiter instantly cuts in.
If I set ZeroDB to -3 the LEDs go down a bit to mid orange, and if I set it to -6 they pretty much stay in the green, but of course the output volume is now far lower.
Are we saying here that in order to avoid hitting just below the limit threshhold we have to use a ZeroDB value as it doesn't seem right with everything on flat the top peak red LED is coming on all the time.
Am I understanding things correctly here?
Posted Tue 27 Aug 19 @ 8:05 pm
the SOUND INSURGENT
Yeah has this changed over the last few updates??
I’ve noticed the same thing but thought I was doing something wrong 🤔
I’ve noticed the same thing but thought I was doing something wrong 🤔
Posted Tue 27 Aug 19 @ 8:08 pm
Adion
That's normal yes, with zeroDb to 0, autoGain's volume will pretty much be a typical average loudness for most tracks, similar to how they were recorded, and thus loud parts getting close to the digital peak.
As long as you properly handle the equalizer/levels during a mix that should not lead to any significant limiting.
If you do want the volume to actually be higher during mixes or when adding samples on top, or absolutely want to avoid the limiter kicking in for any track at any time then you should indeed lower zeroDb to add some more headroom.
Nothing has changed to that recently either.
As long as you properly handle the equalizer/levels during a mix that should not lead to any significant limiting.
If you do want the volume to actually be higher during mixes or when adding samples on top, or absolutely want to avoid the limiter kicking in for any track at any time then you should indeed lower zeroDb to add some more headroom.
Nothing has changed to that recently either.
Posted Tue 27 Aug 19 @ 8:25 pm
kradcliffe
OK, thanks Adion .... just wanted to be sure.
Maybe it's related to my old school mixing days where it was unwise to peak the channel gain too high and stay in the green whenever possible.
Maybe it's related to my old school mixing days where it was unwise to peak the channel gain too high and stay in the green whenever possible.
Posted Tue 27 Aug 19 @ 8:33 pm
Adion
With analog mixers you would indeed start to get some distortion when hitting red already.
With digital sources there is absolutely no distortion up till the end. (Depending on what the vu meters actually display, but within vdj this is the digital peak level. I didn't check the mcx mapper to see if the vu meter is actually software or hardware, and if hardware it might be calculated somewhat differently. In that case you can still use the vu meters on-screen within vdj to check the levels with the explanation I just gave)
With digital sources there is absolutely no distortion up till the end. (Depending on what the vu meters actually display, but within vdj this is the digital peak level. I didn't check the mcx mapper to see if the vu meter is actually software or hardware, and if hardware it might be calculated somewhat differently. In that case you can still use the vu meters on-screen within vdj to check the levels with the explanation I just gave)
Posted Tue 27 Aug 19 @ 9:19 pm
groovindj
You have to bear in mind the difference between analogue and digital audio, and the metering of each.
In VDJ (digital) the signal will be "in the green" right to the top of the channel meters, above which the signal will distort. There's no "overhead". No "grey area" where the signal will degrade slightly. If it goes over, it distorts.
On analogue systems typically the last green (0dB) will be perhaps half way up the meter, with an amber "safety zone" area above that, which you can push into, with the distortion being introduced much more gradually. There is a lot of overhead.
I notice the meters on the MCX8000 have an "analogue" LED layout, with the green (which you'd assume to be 0dB) about half way up. But is that 0dB?
What's the relationship between the VDJ channel meters and the MCX channel meters? At max on the VDJ channel meter, what does the MCX meter show?
In VDJ (digital) the signal will be "in the green" right to the top of the channel meters, above which the signal will distort. There's no "overhead". No "grey area" where the signal will degrade slightly. If it goes over, it distorts.
On analogue systems typically the last green (0dB) will be perhaps half way up the meter, with an amber "safety zone" area above that, which you can push into, with the distortion being introduced much more gradually. There is a lot of overhead.
I notice the meters on the MCX8000 have an "analogue" LED layout, with the green (which you'd assume to be 0dB) about half way up. But is that 0dB?
What's the relationship between the VDJ channel meters and the MCX channel meters? At max on the VDJ channel meter, what does the MCX meter show?
Posted Tue 27 Aug 19 @ 9:22 pm
kradcliffe
They appear to show a similar level to the VDJ on screen channel meter. Although there's nothing wrong on a technical level I just don't like seeing them peaking so high in to the orange then red.
It's a visual thing.
It's a visual thing.
Posted Tue 27 Aug 19 @ 10:09 pm
PhantomDeejay
That's because manufacturers still keep the typical "VU" colors for their "vu-meters" when in fact the metering has changed from analog to digital.
Long story short:
In the analog days a classic VU-Meter was in fact a "special-scaled" Volt-Meter.
VU-Meters were developed in 1939 to be the lingua franca of audio, and not only do they assign 0 dBVU as a meaningful reference point (though not a peak level), but even the meter ballistics are precisely defined (something an electronic VU meter must explicitly emulate if it is to match a moving-coil meter).
0 dBVU was generally defined as the turning point for a piece of audio gear, beyond which distortion would start to increase. Part of the art of recording was deciding how best to trade off distortion in loud passages with noise in soft ones.
To complicate things further 2 standards were soon defined:
-10dbV and +4dbu
The standard consumer (unbalanced) -10dbV standard means that 0 dbVU equals -10 dbV, or, using the dB-to-volts formula:
= 1V • 10(-10/20) = 316.2 mV
It happens that this standard has been defined to carry 2V maximum (sine RMS, or 5.66 VP-P). Thus, we can say it can go up to
= 20 • log( 2V / 316.2mV ) = 16.02 db
In other words the unbalanced signal cannot exceed +16dbVU (and that's what you usually see on typical mixer's line inputs)
Remember: Up to 0dbVU = No distortion!
Greater than 0dbVU = Gradual distortion (so no, amber is not without distortion)
+16dbVU = standard's maximum range (in other words heavy distortion for any value greater than this IF a device tries to send more than 2V)
The pro grade (balanced) +4dbu standard means than 0 dbVU equals +4dbu or (if you do some maths) 1.228V
Also there's not a maximum level defined for this standard.
Coincidentally, this puts the +4dbu reference level almost exactly four times (12db) higher than the -10dbV level, but since the interface is balanced (differential), the actual swing of each line is about twice that of the unbalanced interface…all else being equal.
Why do we care?
To make things more complex modern mixers have analog inputs in -10dbV (unbalanced) standard and use that metering reference point for their inputs.
Almost all mixers have +4dbu (balanced) outputs and some of them opt to show the dbu scale for their output.
In the digital world, you’ll see 0 dbFS (full scale) used, and all levels are negative, since full scale is, well, full scale.
In simple words +0 dbFS is the absolute maximum value you can get.
But how does it correlate with dbV or dbu ?
Well, directly it doesn't.
0dbFS is the maximum value a DAC (digital to analog converter) can/should handle. It's up to the DAC characteristics to determine how it correlates with dbV or dbu.
This means that an "analog like" scale for audio produced by a digital medium (like a computer connected to a controller) is unique to each device that reproduces the digital medium.
Back to controllers:
Most controllers these days leave the software to do all the mixing. Their CH vu-meters are simply MIDI controlled led bars. Since software measures dbFS (and has no way to know the correlation with the controller's DAC(s)) it simply sends dbFS scale values on that MIDI bar. Therefore the vu-meters should be just a solid green bar with one red led on top (for warning when levels hit the 0dbFS mark)
Instead manufacturers still keep the old traditional color scheme that has absolutely no meaning in this case. There's NO area that produces gradual distortion in dbFS.
And in theory a good DAC should produce NO distortion at all up until +0dbFS input.
PS:
1. There is a formula to convert dbV to dbU
2. There is no formula to convert dbFS to dbV or dbU (you should have realized this by now)
3. Some controllers have their CH VU-meters show dbFS and their Master VU-meters show dbU or dbV (this is possible because the voltage reading is done right before the controllers output connectors where the signal is analog). In this case the Master VU-meters are controlled by the device and not by MIDI.
This is somewhat the worst case scenario (which is quite common these days, especially with Pioneer controllers)
The reason is that the end user (DJ) sees two different scales without him actually knowing it and thus without knowing how to treat/interpret them. To make things worst, these different scales use the same color scheme (as it has been said already) which makes confusion even greater.
Let's all hope that manufacturers will soon change that logic, or that more DJ's will understand the difference between db scales (highly unlikely)
Long story short:
In the analog days a classic VU-Meter was in fact a "special-scaled" Volt-Meter.
VU-Meters were developed in 1939 to be the lingua franca of audio, and not only do they assign 0 dBVU as a meaningful reference point (though not a peak level), but even the meter ballistics are precisely defined (something an electronic VU meter must explicitly emulate if it is to match a moving-coil meter).
0 dBVU was generally defined as the turning point for a piece of audio gear, beyond which distortion would start to increase. Part of the art of recording was deciding how best to trade off distortion in loud passages with noise in soft ones.
To complicate things further 2 standards were soon defined:
-10dbV and +4dbu
The standard consumer (unbalanced) -10dbV standard means that 0 dbVU equals -10 dbV, or, using the dB-to-volts formula:
= 1V • 10(-10/20) = 316.2 mV
It happens that this standard has been defined to carry 2V maximum (sine RMS, or 5.66 VP-P). Thus, we can say it can go up to
= 20 • log( 2V / 316.2mV ) = 16.02 db
In other words the unbalanced signal cannot exceed +16dbVU (and that's what you usually see on typical mixer's line inputs)
Remember: Up to 0dbVU = No distortion!
Greater than 0dbVU = Gradual distortion (so no, amber is not without distortion)
+16dbVU = standard's maximum range (in other words heavy distortion for any value greater than this IF a device tries to send more than 2V)
The pro grade (balanced) +4dbu standard means than 0 dbVU equals +4dbu or (if you do some maths) 1.228V
Also there's not a maximum level defined for this standard.
Coincidentally, this puts the +4dbu reference level almost exactly four times (12db) higher than the -10dbV level, but since the interface is balanced (differential), the actual swing of each line is about twice that of the unbalanced interface…all else being equal.
Why do we care?
To make things more complex modern mixers have analog inputs in -10dbV (unbalanced) standard and use that metering reference point for their inputs.
Almost all mixers have +4dbu (balanced) outputs and some of them opt to show the dbu scale for their output.
In the digital world, you’ll see 0 dbFS (full scale) used, and all levels are negative, since full scale is, well, full scale.
In simple words +0 dbFS is the absolute maximum value you can get.
But how does it correlate with dbV or dbu ?
Well, directly it doesn't.
0dbFS is the maximum value a DAC (digital to analog converter) can/should handle. It's up to the DAC characteristics to determine how it correlates with dbV or dbu.
This means that an "analog like" scale for audio produced by a digital medium (like a computer connected to a controller) is unique to each device that reproduces the digital medium.
Back to controllers:
Most controllers these days leave the software to do all the mixing. Their CH vu-meters are simply MIDI controlled led bars. Since software measures dbFS (and has no way to know the correlation with the controller's DAC(s)) it simply sends dbFS scale values on that MIDI bar. Therefore the vu-meters should be just a solid green bar with one red led on top (for warning when levels hit the 0dbFS mark)
Instead manufacturers still keep the old traditional color scheme that has absolutely no meaning in this case. There's NO area that produces gradual distortion in dbFS.
And in theory a good DAC should produce NO distortion at all up until +0dbFS input.
PS:
1. There is a formula to convert dbV to dbU
2. There is no formula to convert dbFS to dbV or dbU (you should have realized this by now)
3. Some controllers have their CH VU-meters show dbFS and their Master VU-meters show dbU or dbV (this is possible because the voltage reading is done right before the controllers output connectors where the signal is analog). In this case the Master VU-meters are controlled by the device and not by MIDI.
This is somewhat the worst case scenario (which is quite common these days, especially with Pioneer controllers)
The reason is that the end user (DJ) sees two different scales without him actually knowing it and thus without knowing how to treat/interpret them. To make things worst, these different scales use the same color scheme (as it has been said already) which makes confusion even greater.
Let's all hope that manufacturers will soon change that logic, or that more DJ's will understand the difference between db scales (highly unlikely)
Posted Thu 29 Aug 19 @ 8:27 am
kradcliffe
Bit too technical for me George, but at least I now know I can set ZeroDB at - 3 and not worry about the orange LEDs
Thanks for all your help.
Thanks for all your help.
Posted Thu 29 Aug 19 @ 9:06 am
PhantomDeejay
Ok, much less technical resume:
PhantomDeejay wrote :
Most controllers these days leave the software to do all the mixing. Their CH vu-meters are simply MIDI controlled led bars.
Therefore those controllers have their CH VU-meters show dbFS and their Master VU-meters show dbU or dbV
This is the worst case scenario (and it's quite common these days)
The reason is that the end user (DJ) sees two different scales without him actually knowing it and thus without knowing how to treat/interpret them.
To make things worst, these different scales use the same color scheme which makes confusion even greater.
On those cases CH vu-meters should be just a solid green bar with one red led on top
Therefore those controllers have their CH VU-meters show dbFS and their Master VU-meters show dbU or dbV
This is the worst case scenario (and it's quite common these days)
The reason is that the end user (DJ) sees two different scales without him actually knowing it and thus without knowing how to treat/interpret them.
To make things worst, these different scales use the same color scheme which makes confusion even greater.
On those cases CH vu-meters should be just a solid green bar with one red led on top
Posted Thu 29 Aug 19 @ 12:02 pm
kradcliffe
That explains it perfectly. I will keep the channel gains in the orange with - 3 on ZeroDB and keep the master output on zero.
I use the Bose F1 system so there's loads of headroom on them anyway.
Thank you for the explanation.
I use the Bose F1 system so there's loads of headroom on them anyway.
Thank you for the explanation.
Posted Fri 30 Aug 19 @ 7:13 pm