/* Google analytics tracker */ John the Revelator: So you wanna be a karaoke host? (Part 5: Mixing it up)

Monday, April 5, 2010

So you wanna be a karaoke host? (Part 5: Mixing it up)

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A mixer, in it's simplest form, is just a box that combines the signals from one or more mics along with a music signal in order to create a single signal to send to your amp. That's all it really is, but somewhere along the way it got more complicated.

This article is orgamized in such a way as to start you off thinking it is all gonna be really cheap, then suggest that it will really be more, and then finally leave you at the point of "how can I afford not to go all out?"

Taking it simple (CHEAP) first
Let's have a look at the simplest (and cheapest) options for a mixer. Along the way, we will see the features that get added for a price.

One of the simplest mixers is exemplified by the Nady MM-141, which sells for $30.


This particular mixer will combine four mics into one, with a separate volume control for each mic, and then another overall volume control.

Wow. What else could someone possibly want?  Seems like this is all you would need for a mixer. Pipe this into a a set of active speakers, or into an amp and speakers and you are all set. Well, except for a few things. Most importantly, the music.

Let's say that you are running your karaoke show with a laptop. You have the karaoke music coming out of your laptop, but where is it going? Your laptop speaker output should go to the mixer. The job of any self-respecting mixer is to combine the music with the voices of the singers and allow you to balance one against the other.

It would seem at first glance that this cute little mixer has you covered. Four inputs? That sounds like three mics and one input for the music. Cool.... Except.

The inputs for this mixer are mic inputs. They are (go figger) designed for mic level inputs. Your computer puts out a different signal level, called "line level", which is suitable for headphones and amplifiers. I will discuss the difference between these two levels in another section of this tutorial ("Tying it all together"). Suffice it to say right now that to balance the music and the mics, you would need to turn the music all the way down and the mics all the way up. Once you get it balanced, you really don't have much breathing room left to adjust either music or mics during a show.

Oh yeah, and then there is the issue about stereo. The inputs to this simple mixer are mono. To connect stereo up to this, you need to take two of the inputs, one for each channel. And the output of the mixer is also mono, so you have lost the stereo effect. That might not be an awful thing. I would argue that while stereo is a nice thing to have, it is not crucial for karaoke.

But still, I do not recommend this mini mixer for karaoke. 

Bringing in the music
There is another cheap solution that will allow you to mix in a mic: your computer. Sound cards on computers often have a place to plug in a mic. Within the sound card, there is a mixer that will combine the mic input with the music that your are playing, and send this out the line out of the computer.

Which is pretty much what we want, right? Well... once again I intend to try to pop your "I can get my karaoke gear real cheap" bubble.

There is a lot of variability in the quality of mic inputs on a sound board, and this is especially true on  the sound card for a laptop. These inputs were designed for the speaking voice, not for singing. If your mic input is not good enough, you could go with an external sound card. This device (Sabrent USB 7.1 CH 3D) plugs into a USB port and provides two mic inputs. It sells for $24. 
I have one of these. Perhaps I am missing something, but there does not appear to be separate volume controls for the two mics. But in my opinion, a bigger problem is that the volume controls for this box are  software controls. To adjust the volume of the mic, you must first bring up the volume control window, and then adjust it with the mouse.

While this may seem pretty easy just talking about it, but you probably won't think so the first time someone screams into the mic. Why do people do that? I don't know. But they do, and when they do, you need to be right there on the volume control to assert your own dominance. You are in control. You are the alpha KJ.

The solution to both of these problems is to use the two boxes together. I should clarify. The solution to the problem of separate controls for the two mics and of mouse controls is to use the USB sound card and the mini-mixer. All your mics would plug into the mini-mixer and the mini-mixer would plug into the Sabrent sound card.

I don't have a solution to the problem of people screaming into the mics.


While this setup (mini-mixer and USB sound card) would (should) all work just hunky-dory, I'm not going to recommend it.

But before I move on, there is one cool thing you can do with a USB sound card. You can have two sound outputs going at the same time: one for KJ and the other for DJ. I will talk about this in a future blog. 

Mixing it up for under $100
I found five mixers for under $100 that I would call "adequate" for karaoke. True to my noncommittal ways, I am not going to recommend any of these mixers.

When I say adequate, I mean "don't come crying to me when you decide you want something bigger and better". When I say adequate, I mean "base level functionality". (Also, when I say adequate, it also brings back some bad memories of what she said after the first time I "did it". I mean, after the first time I did karaoke, of course.)

What are the base level functionalities?
In my opinion, there needs to be at least two mics, so the mixer has to have at least two mic inputs. When  running with two mics, the KJ has one mic and the singer the other. When two people get up to sing, the KJ passes the mic to the second singer.

There must be at least one stereo, line level input to plug the computer sound output into.

There must be separate volume control for each input. It is imperative to have a volume control on each mic because of the huge variation in volume between people.

There must be a stereo main out (for the club speakers) and then a second output. This second output might be called monitor out or control room out. These outputs must each have a volume control. This second output will be used to run a monitor speaker or two. A monitor is a speaker that sits on the floor, pointing toward the singer. This speaker allows the singer to hear their own voice. In my opinion, a monitor speaker is absolutely essential.

In a pinch, you can use a headphone output to run the monitor speakers. A few of the mixers above have only this as a second output. This is not as good as a real output, but it allows us to achieve base level functionality.

Additional features
So, if I limit myself to spending $100 on a mixer, what great features might I miss?
More mic inputs - To me, it just seems a bit pedestrian for the KJ  to be exchanging the  mic back and forth with the singers, so I think you need a lot of mics, and hence a lot of mic inputs. I normally run with three mics just for the singers. If I am running the gig with another KJ, I will have two additional mics. I don't know if I mentioned this or not, but I am a fabulous karaoke host.

Second stereo line input - Hey, did you know you can hook your iPod into a mixer?  And that it will sound good?  I always bring some sort of mp3 player with me whenever I run a gig. It can provide background music between singers. Just leave the iPod running and bring the volume up on that channel between karaoke songs. Also, the iPod can provide music while you are setting up or tearing down. You can pack up the laptop while you still have tunes going. Finally, having the iPod always ready can help you avoid complete humiliation if the karaoke software crashes. To run an iPod like this, you need to have a second stereo line input.

Sliders - Sliders are just cool. I like sliders. It makes me feel like I am Scottie, running a transporter. I like a mixer where the main output volumes are all controlled via sliders rather than knobs that you turn.

Special effects - This feature is often written "Special FX". (If you are cool, or if you want people to think you are cool, you will also abbreviate effects  as FX.)  Special effects can make a mediocre singer sound great. In order to get that true American Idol sound, you really need to add a little reverb to a voice. Or that's the thought. On the other hand, reverb can make it more difficult to control feedback. It also will take some learnin' to go from "ewwww.... that's sounds like too much reverb" to "wow!  is that Dannie Gokey?"

Bass and treble on mic input - A bass and treble control on each mic input allows you tailor the sound to the person's voice. When I use these, it is most likely to turn down the treble on a shrill voice.
Bandpass equalizer on output - All rooms are different, all speakers are different, songs are different, quiet sound needs more bass. All these require that you have some control over the equalization of the final output. Having five channels is nice. Seven? Gee I dunno. Do you need it? Do you have time to tailor it for each gig, or will they always be set to whatever you used at the last gig?

Level set LED indicator - My mixers have little LEDs next to each mic input to tell me when the signal level is starting to get too high. I try to keep the signal level just below the point where this LED flashes.

More better mixers
Here are some examples of mixers that I would consider pretty darn good for karaoke. They all run from $200 to $300. Note that the basic price difference has to do with the number of inputs.

This is the Mackie ProFX8, selling for $230.


Here we have Yamaha's MG124CX, coming in at $290.
And here is the Peavey PV14, with a price tag of $300.


Which to buy?  I dunno. I have two Mackie mixers (one a little bigger than the ProFX8, and one a little smaller -- both older models), and I have one Yamaha powered mixer that is real old. I use the Yamaha mixer most often, simply because it has the built in amp. Convenience. I think I like the mixer functionality a bit better, but partly that's just my own familiarity.

Running a mixer
Mixers have a lot of buttons and switches. It will necessarily take a while to learn how to run the crazy thing. I will save that long discussion for another blog, but I will motivate the discussion a bit.

If the volume of a singer is too high, you could ask the singer to sing quieter. You could ask the singer to hold the mic further from their mouth. You could lower the gain knob right next to the input plug. You could lower the bass, midrange, and treble controls for that mic. You could lower the AUX or the Main for that mic. You could lower the main mix volume. Or, you could lower the volume on the amp. All of these will serve to lower the volume of the singer. Which is the correct one to adjust?

When I first started running a mixer I found that my knobs would run away by the end of the gig. Eventually, certain knobs would be pushed all the way one way. I didn't know how they got there, except that every time I adjusted a knob I was doing something that made sense. The thing is, I knew what each of the knobs did, but I did not have a coherent strategy for adjusting them.

There is some artistry to running a mixer and there is some science. I will go into that deeper in another blog. 




Copyright (c) 2010, John Seymour

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