How do I set my gain knobs?

[Neeps]

Hello folks this is my first post here at sos so nice to meet everyone.

I've got a question that's been bugging me it's probably very simple and I was hoping someone might help me out and answer it.

My signal chain goes like this:

Mic > M-Audio DMP3 > Behringer UB2442fx mixer (for monitoring while tracking) > EWS88MT audio interface > cubase.

I know that when I record I want to keep the levels reasonably high but avoiding clipping... but what I wondered is does it matter which volume control I use to boost the level?

First off there's the gain on the DMP3. Then there are two gains on the mixer, the main fader and something else called trim. I think there's even an input volume on the EWS88MT's control software that I never go near.

How should I set this up... should I set the trim to 0 and the fader to 0 and only use the DMP3 gain? If the trim is set at 0 will the behringer mixer be degrading my signal? I once tried the inbuilt 'invisable' preamps and they were murder. Really poor.

Thanks for any help

Cheers
Barn Owl

 

[Fletcher]

If you're just using the mixer for monitoring then don't worry about how you have the gain setup on the mixer and concentrate on the signal chain. My advice would be to set your input gain on the mixer at the same level straight across the desk, set the faders to a set level across the desk [-5 usually works]. Then use the DMP-3 to set the level going into Cubase [have the levels in Cubase at a set level and don't mess with those levels unless you plan on "mixing in the box"... in which case you can vary them later].

Now try to achieve a balance to the sounds of your recording while using the gain settings on the DMP-3. The theory being that everything else should be set at or near "unity gain" while you have one variable in the program.

Understand that the pre amps in the DMP 3 are probably not going to give you results like that of a "professional" recording... but it will definitely get you started down the path of learning how to play the instrument I like to call "recording studio".

Best of luck with all you do!!

 

[Neeps]

My advice would be to set your input gain on the mixer at the same level straight across the desk, set the faders to a set level across the desk [-5 usually works].

Thanks Fletcher... i'm getting there but not quite

Ok so all the faders get set to -5 but what about this trim knob on the behringer? As I understand it that's the gain knob for the inbuilt mixers preamps. If it's sitting at zero are the behringer preamps in the chain? When tested alone the preamps were horrible and tinny I don't want them in the chain even if they are turned down low.

The theory being that everything else should be set at or near "unity gain" while you have one variable in the program.

You've lost me there... what's "unity gain"?

Understand that the pre amps in the DMP 3 are probably not going to give you results like that of a "professional" recording... but it will definitely get you started down the path of learning how to play the instrument I like to call "recording studio".

Best of luck with all you do!!

Oh crap!

 

[Fletcher]

Unity gain means you have the same level going out as you have coming in... its all part of "gain staging" [also known as "gain scaling"]. I'm sure there is some "audio dictionary" thing somewhere on the web that can explain the concept better than I can.

Peace.

 

[Robert D]

Hi,
From your signal chain description, and the wording of your question, it sounds like you're going from DMP3 to Behri mixer channel to audio interface. If so, you'd be much better off going directly from the DMP3 to the interface, and monitoring the interface in hardware monitoring mode, rather than going through the mixer to monitor on the way to the interface. This is for two reasons;

1 - If you clip the converters, but are monitoring before the converters, you won't hear it.

2 - The Behringer shouldn't be mucking up the sound by being in the recording signal path. The DMP3 is really a pretty decent piece of preamp for clean gain, but putting the behringer in line with it is like looking through a clean piece of glass AND a dirty piece of glass stacked together. It doesn't matter how clean the first piece of glass is, it can't make the 2nd piece any clearer.

 

[maestro_dmc]

Hello folks this is my first post here at sos so nice to meet everyone.
Cheers
Barn Owl

Let me be the first to welcome you here, to the lovely forums of SOS.

As for the gain staging I look for a link that explains it.

If the DMP3 has two outputs, run the unbalanced one into your Behri for monitoring, and run the balanced one(if it exists) into the terratec (if IT has balanced inputs) This is the best way to avoid the nasty behri pre's, and still monitor.

 

[Neeps]

Let me be the first to welcome you here, to the lovely forums of SOS.

As for the gain staging I look for a link that explains it.

If the DMP3 has two outputs, run the unbalanced one into your Behri for monitoring, and run the balanced one(if it exists) into the terratec (if IT has balanced inputs) This is the best way to avoid the nasty behri pre's, and still monitor.

Oops... I posted the same question over at www.soundonsound.com

You guys are much better nobody answered me over there!

The DMP3 only has one output per channel so I guess i should try to figure out if I can do hardware monitoring with my terratec ews88mt like Robert D suggests. Or could I use a cable that splits in two?? Or is that a bad idea? Sounds like good reasons to ditch the behringer although I guess I'll still use it to give me something to plug my monitors and headphones into.

 

[snow lizard]

I know that when I record I want to keep the levels reasonably high but avoiding clipping... but what I wondered is does it matter which volume control I use to boost the level?

You don't necessarily want to keep the levels reasonably high but avoid clipping. The DMP3 has VU meters and a clip light on it, so you should try aiming for a signal that runs around 0 VU without making the clip light go all spastic. You can try to adjust the level for specific sounds that you're recording to where you like it. Experiment.

If you're recording drums or something that has fast transients, you may want to back off the gain a bit. Especially if the clip light starts freaking out. If it blips once in a while, that's not usually a problem.

As for where your levels end up in Cubase, you might find that a 0 VU signal will leave you somewhere between around -12 to -20 dBfs. If that seems a bit low, you might want to consider that it isn't.

There's a lot of information out there telling you to print (record) signals as hot as possible to get the best "digital resolution" or something like that. I can show you what that means mathematically, but it's irrelevant when you consider headroom.

Running a static signal like a sine wave at 0 VU through your preamp means that there's headroom above that signal before the amp goes into distortion. Maybe 12 dB, maybe 20 dB or more, it depends on who designed the preamp. Headroom is important to keep the signal clean.

Converters are designed to take a signal like that without going into distortion. Your interface probably doesn't have clip lights to tell you if it goes over, but it's not going to help it sound any better.

The final digital level you have in Cubase will clip if it goes over 0 dBfs - this isn't 0 dBVU - they're completely different things. So let's say that your amp has 16 dB of headroom, and you end up with a level of around -16 dBfs in Cubase. That's normal, and sort of how it was all designed to work anyway.

If you were to try to get as close as possible to 0 dBfs in Cubase, you could crank the gain up on the DMP3. This means that you might be distorting the preamp, distorting the converters, and running the risk of having a digital "over", or a signal that exceeds 0 dBfs. It's a bad idea, despite a lot of information to the contrary. Especially if you're printing a lot of tracks, when you go to mix, the individual levels of the tracks will sum together giving you more sound level anyway. It isn't necessary to print hot levels to get there. It kind of ruins things.

Again, it's something you might want to experiment with to see what works best for you.

And yeah, you should be just fine with the DMP3 straight into the interface.


Good luck,


sl