Mixers and Home Recording

[Bobbsy]

Good point, Hakea. I've done an edit to add a section about "mixers as a control surface" which should clear this up.

[arcadeko]

Maybe we could integrate this with the interface thread or something - I think one thing that we take for granted and newbs do not understand is that a mixer is not an interface, an interface is not usually a mixer, although some interfaces have mixers... Anyway - to make it more complicated it can be very difficult to tell the difference from a glance at a piece of equipment - you have to read the specs... so we need to really clearly explain the difference between the two and which is appropriate for which task.


forgot to mention: Nice job Bobbsy

[Capt Hair]

Very useful post!. Good one Bobbsy.

The only thing that I'd suggest adding is just a bit more clarification (or emphasis) about the difference between a CONTROL SURFACE and a MIXER as it seems to be common for newcomers not to understand the difference.

From reading posts here I think that many newbies buy a cheap mixer thinking that all those attractive knobs and sliders can be used to control the mixing in their DAW, and then get baffled when they can't figure out how to hook it up to do that.

Cheers,

Chris

I know I was guilty of thinking that when I first got here lol.

Luckily no one bit my head off for asking the difference between the two

[jtech3]

Very cool overview I agree completly

[jtech3]

I agree completly. Very good overview

[Shleuven]

Thanks, very useful post!

[deaf clef pro]

So I'll be the one to ask...what is a "DAW"? Digital Audio Workstation? Dirty Aging Woman? Driver-Angled Wedge? I get that an interface is just a device to interpret and consolidate the signals from individual inputs to a digital fomat a computer can use and am attracted to the idea of a mixer which also serves that function for simplicity's sake (one les peice of equipment generating RF and sucking up AC voltage). Some more questions to show my sheer ignorance...what's "line-level" and "headroom"? I know a pre-amp is a device which adds overall gain to an incoming signal and have experinced the limitations of crummy pre-amps (a donated Art Tube MP Project Series which is very noisy).

[Bobbsy]

Well, in this context, DAW is, indeed, "Digital Audio Workstation" in this context (though I prefer "Delicious Australian Wine").

An interface is exactly that: a device to interface from analogue audio signals to digital information a computer can handle and back again so you can listen to your stuff. Most interfaces have three main functions built in: mic pre amps to bring your mic signals up to line level for processing, analogue to digital converters to change the line level signals to digits for the computer (plus digital to analogue so you can play stuff back) and some form of monitoring system so you can hear a mix of playback and the material you're recording in your headphones. Note I said "most" interfaces--you always need to check the specs carefully to make sure a feature you need hasn't been left out.

Line level is the typical signal level used by audio equipment like mixers, CD players, etc. for processing and outputting audio. It's referenced to a specific voltage of signal? What voltage? It depends. There are slightly different specs used by professional gear and amateur equipment and some variations from country to country and application to application. If you want to read up on it, there's a good Wiki article on this topic. However, suffice to say that line level had enough voltage to travel over fairly long cables and be relatively resistant to interference. Typically, devices that output line level plug into mains electricity or at least have a battery pack to provide power.

There are two other main "standard" levels you'll hear talked about: mic level and instrument level. The output of microphones is a very low level--typically 40 to 60dB less than line level. This is because the output is generated (or at least modulated in the case of condensers) by the small movements caused by sound pressure waves in the air. As such, mic level signals are more prone to interference over any distance. This is why mic level signals need to be brought up to line level by a mic pre amp, hopefully as early in the chain as possible. Instrument level is what you get from things like electric guitars or pickups on violins. It sort of sits half way between mic level and line level.

Headroom is the difference between the nominal signal level and the point at which electronics run out of steam and start to clip. In the analogue world, this is typically around 18dB above line level but every bit of gear is different. I've seen some pro gear that claims 22 or 24dB above line level--and other stuff the clips at as little as 10 or 12dB above line level. Headroom in the chain, particularly with live mics, is important since it's quite common for a vocalist to idle along at a certain level, then suddenly get hugely louders briefly. There are faqs here on the site that give details of what levels you're working at.

If you decide to go the mixer route, I strongly recommend you read and head the advice in this sticky about checking how many outputs your mixer has and also the routing options for headphone monitoring. These seem to be the two weak points of a lot of economy mixers (a third being noisy pre amps of course).

[deaf clef pro]

Very well articulated, thank you!

[ga3music]

thank you , it helps me alot.