Metering problem or maybe not.

[MatthewRedStars]

Hi.

It goes something like this.... I record via a Alesis Multimix in Cubase. When recording I get a nice level -12 db or whatever on my multimix using the gain pot and set the faders (knobs) to unity.

In Cubase the software mixer shows a similar-ish level. The waveform looks nice. I'm pretty sure this is all good.

The problem is that when i playback through my Multimix without touching anything, the hardware meters clip light lights continually, but with no audible distortion. Surely -12db audio should show as -12db on the hardware output meter?

Is there a different calibration standard for output, am i doing something wierd on playback or is my multimix being screwy?

Thanks
Matthew.

 

[dturcotte]

How many channels are you playing back?

 

[MatthewRedStars]

A few.... i appreciate that they all add up but the output Bus is not even close to 0db.

 

[Farview]

-12db in a digital system equates to +6db in an analog system. It's two completely different scales.

0dbVU (analog) = -18dbFS (digital)

 

[MatthewRedStars]

Cheers! those numbers work.

 

[Erockrazor]

In analog , the signal level of 0dbvu is not supposed to be clipping. Thats supposed to be around the best signal level to get your analog equiptment to. Many analog preamps and mixers can go above 0dbvu and not exhibit clipping for a few more db's.

But digital signal levels are less forgiving. Once you get to 0dbfs there will be clipping. I'm pretty sure that when you have your mixers signal level peaking around 0 dbvu , your softwares digital peaks should be around 18dbfs. There is reasons as to why the numbers may be a little bit different , but thats where my knowledge gets really fuzzy.

The good news is that nothings wrong with your rig

 

[whjr15]

In analog , the signal level of 0dbvu is not supposed to be clipping. Thats supposed to be around the best signal level to get your analog equiptment to.

Ok, so I record as close to 0dbvu as possible:

I'm pretty sure that when you have your mixers signal level peaking around 0 dbvu , your softwares digital peaks should be around 18dbfs.

...but isnt 18dbfs massive clipping?


I dunno, Im lost I ask this because (and I dont mean to hijack the thread, but its too close to this topic to start a whole new thread) I just did a test.....

I recorded single notes from my keyboard peaking almost exactly at 0 on my mixer. Then I checked the levels in my software, and it says -6. wtf??

I guess I just dont grasp the whole "conversion factor" thing.

 

[Farview]

...but isnt 18dbfs massive clipping?

He meant -18dbfs

I recorded single notes from my keyboard peaking almost exactly at 0 on my mixer. Then I checked the levels in my software, and it says -6. wtf??

It was a sound like a piano or something with a percussive "plink" to it. That is the problem. Try it with an organ or a string pad ( choir, anything steady) and you will get a different result.

The VU meter on your mixer is measuring average level. The meter doesn't see sharp fast transients, like the sound of the hammer hitting the piano strings.

The meters in your DAW are peak meters, they are very fast and do see the transients.

Not only are VU and FS completely different scales, but they are measuring tow different things.

 

[whjr15]

Ohhh ok... That cleared up a lot. I'm gonna try the string patch now and see the results first hand... It's always easier to understand once you experience it.

Sorry erock for disputing you. It's funny how something as little as a " - " can throw something way out of proportion.

 

[Farview]

Different instruments read differently on the different meters. Once you get a feel for what you are listening to, it will all work out.