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Posted: 10/11/2007 9:37:32 AM EST
[Last Edit: 10/11/2007 9:38:33 AM EST by pv74]
Somehow, I don't know how...I ended up running the music rehersals for a gospel service.

I used to set up a few microphones and mix the voices in with a CD, then send it to the speakers...

But recently, a keyboardist with some talent and a decent drummer showed up...so we want to do some live music.

The chapel uses a Soundcraft Spirit FX16 mixer.

I wanted to connect a Yamaha keyboard into one of the microphone inputs, so I disabled the 48 volt microphone voltage. All but one of the micrphones that we run do not require this voltage. If I turn the mic gain way down it works ver well.

The Catholics use the microphone that requires 48 volts and they don't sing...so it's not that big of an issue....just curious if some idiot would fry the keyboard if he hit the microphone voltage button.

I take it that if I left the microphone voltage enabled that I would fry the keyboard?

I use an adapter to hook the keyboard stereo phono jack into a standard microphone input.

Also, the drummer needs to here the keyboard on stage, so I hooked a guitar amp to a mono output on the keyboard and placed it near the drummer. Is this OK to do this without damaging the keyboard...run a stereo output to the mixer board and a mono output to an amp at the same time?

The keyboard output jack is labeled R/L.....L ( one output is stereo or right chanel mono, and the other one is just left channel mono).

Anyone know about this stuff or can you point me to a website to learn about it?

Link Posted: 10/11/2007 9:38:51 AM EST
Well you plug stuff into it, then you move the knobs and sliders around, then it makes music sound different...
Link Posted: 10/11/2007 9:40:30 AM EST

Originally Posted By killswitch1982:
Well you plug stuff into it, then you move the knobs and sliders around, then it makes music sound different...

Already doing that
Link Posted: 10/11/2007 9:49:24 AM EST
[Last Edit: 10/11/2007 9:51:18 AM EST by daveisadork]
Just to be clear on terminology...

Pictured above are RCA connectors.

Pictured above are XLR connectors.

Pictured above on top is a TRS (¼" balanced) connector and on bottom is a TS (¼" unbalanced, or instrument) connector.

Now... which one are you plugging into the keyboard, what kind of adapter are you using and which one are you plugging into your console?
Link Posted: 10/11/2007 9:58:23 AM EST
[Last Edit: 10/11/2007 10:01:33 AM EST by kap_x]
Phantom power shouldn't hurt it one bit.
If you have the phantom power switch on and the mic is dynamic, it's fine. It should be the same for keys.
I don't know what would have to be going on in the sound booth for it to get knocked on anyway

ETA: Is it an adaptor from TRS/TS to XLR, or is it a Direct Input box (a box that does the converting?) If it's the former, it will probably sound like doodoo
Link Posted: 10/11/2007 10:24:26 AM EST

Originally Posted By kap_x:

ETA: Is it an adaptor from TRS/TS to XLR, or is it a Direct Input box (a box that does the converting?) If it's the former, it will probably sound like doodoo

We have one of those adapters on the input line with our wireless mic .
It's really hard to mix well.

I'm another "what does this button do" church mixer (I use some variety of digitial Behringer Eurorack).
Link Posted: 10/11/2007 10:56:14 AM EST
I have more than once accidently flipped phantom power on while my KBs were connected to mike inputs, with no known damage. From there, YMMV.

Set your board up for unity gain. A mixer is not an amplifier. Amplifiers do that kind of work better, cleaner and more efficiently. A mixer is a pre-amplifier, among other things, but not an amp. You can raise mike level signals (0.1 volt, take that with a grain of salt) to line level (1 volt), but not to speaker levels (10 volts) using a mixer.

Assume a simple 12x1 mixer, 12 mono inputs, 1 mono output. Assume this is a Peavey board, because I know they are designed with unity gain in mind, Marty McCann told me so personally.

Set your output fader to 0 db. To illustrate an important point, if you then raise the main to +3 db, you have doubled the amplifier power applied to the signal, important relationship. The smallest increase in sound prssure level (loudness) you can detect is 3db, and doing that involves doubling the amplification. At +3db, your mixer is acting as an amplifier, not good, set it back to 0 db.

Now, if you run two imput channels, aay a mike and a KB, and both input faders are set to 0 db, then you are doubling the power, making your mixer an amplifier. So you halve the power on each of the 2 input faders, and you do that by setting them at -3db, because of the important relationship outlined above.

If you use four input channels to the mono main out, you'd set all four at -6 db.


Consider this your starting point, and the levels advised sort of your red lines, as in do not exceed. You may not blow anything up exceeding these levels, but you will probably surpass the ability of the device to act as an amplifier, meaning you introduce signal clipping and distortion into your audio chain. Any chain, including an audio chain, is only as strong as its weakest link, and once you introduce avoidable distortion into the chain, it's there to the bitter end, your speakers, and you will probably hear it. You may damage downstream components too.

To equalize (match in loudness) various inputs then, you CUT fader levels, and avoid exceeding your basic setup redlines. If you can't hear the KB, you cut the mike, don't boost the KB. Room SPL is controlled at the master output fader, cuts only, unless you know what you're doing and why, above 0 db.

Obvious note to me, but probably not for a beginner, all your channel EQ controls should be flat at this point, no cut, no boost. FX and monitor sends off, we're not there yet.

Your mike and/or line input controls (sometimes called "pads") should produce the general RELATIVE SPL levels you want with the board set at basic unity gain, as little as necessary to achieve this result.

You can run the show from here assumnig the rest of your audio chain is set and performing properly. Hhowever, the mixer offers you much more control and why waste it?

To adjust spectral timbre, use the channel EQ controls. Simple bass/treble or bass/midrange/treble controls act as a 2 or 3 band graphic EQ. Parametric EQ is more complicated and I won't confuse you with this unless you tell me your board has it.

If the board has EQ controls on the master outputs, use this to tune the room. Some rooms spike or dip at certain frequencies, these controls offset this. Channel EQs are for adding sparkle or punch to individual instruments.

ALWAYS cut EQ, NEVER boost EQ. If you're not hearing enough treble, cut the bass and midrange, the adjust your channel faders, keeping unity gain in mind, don't boost the treble. It's a mixer, not an amplifier, remember? Once you understand this, there are exceptions, but not now. For now, always cut EQ. ok?

What you are doing with the two outputs of the KB is a function called monitoring. The drummer is monitoring the KB, but the way you have this set up, this is taking place outside your control. If the KB player turns up his amp, the drummers KB monitor will increase it's output too.

Monitors ALWAYS drive the room, in addition to your main speaker arrays. (Drums drive the room too, instrument amps, etc, and they CAN, but don't have to, interfere with YOUR ability to precisely tune the sound system for optimal room acoustics.) Monitors MAY drive the room at noticable levels, and they may drive the room at less noticable levels, and then there's the grey area which is of highest concern, when the monitors drive the room only at certain frequencies and create phase cancellation issues. OR feedback, that excruciating high frequency shriek or that low end rumble.

Because your monitoring circuit does not run through your mixing board, you cannot control any of these effects.

The monitor section of your mixing board may be thought of as a nearly seperate mixing board. On each channel, there is a monitor send fader or rotary control (called a "pot", short for potentiometer). This is like the channel fader on your main board. Over to the right (in the center on high end studio boards) you have the master monitor controls. These are anagalous to your main output controls on the main mix section.

If your board does not have monitor controls at all, you can use one or more FX sends for the purpose, but you lose effects options this way.

The monitor controls need to be set for unity gain just like the main controls were.

To do accomplish what you are doing, such that you have control requires a bit more cabling. Just plug the board's main monitor output into the drummers monitor speaker the way you used to have the KB's extra out plugged into the drummer's monitor and voila, you have control.

To give the drummer more KB SPL, increase the monitor send level on the KB channel control, or increase the monitor master out control setting. Remember the limitations imposed by unity gain. This separate monitor section allows you to create a completely different mix, for the people onstage to hear. It also allows you to tune interactions between the stage monitors and mains.

The FX send/return sections of the board act as a third separate mixer, with a few more variables. Basically, you are splitting individual channel signals, selectively sending part to the main outs of the board, and sending part to an FX processor. Then, in some cases, you will bring the resulting processed signal back into the channel circuits, or in some cases back into the mains, to go out with the unprocessed signals.

This is a basic overview, and about as far as I want to go without specific questions relating to your board. There are hundreds of millions of variables, no sense wasting time till we know what you want to know.

Hope this helps, feel free to PM with additional questions if necessary.

Link Posted: 10/11/2007 11:34:04 AM EST
If the vocals are unintelligable, sounds like they are mumbling, not enough treble. If the S's are sizzling, too much treble. If they sound boomy, like singing in the shower, reduce the bass. Try to make the voices sound natural, not "enhanced". Add just enough reverb to add some warmth to the sound, so it is not dry. How much depends on the amount of natural revereration already in the room sound.

Start off with the mics at about 40%-50% (4-5 on a 0-10 scale). Set the overall volume with the Master Gain (or volume knob). Then adjust the individual mics up or down to balance with the others.

If you run the mic channels too low, you have to boost the Master Gain too much, and amplify noise and hum. If you run the mic channels too high, they may distort, and you have to run the Master Gain almost all the way down.

Begin with the treble and bass knobs on each mic centered (0), and slightly boost or cut treble and bass (or they may be labeled High and Low EQ) to get each mic to sound natural.

Link Posted: 10/11/2007 2:38:09 PM EST

Originally Posted By Quintin:

Originally Posted By pv74:
Here is a picture of the mixer board:


Wow, there's a lot of buttons and knobs and dials on that thing.

I think I could seriously fuck something up with that many thingies to push, turn and slide.

The traditional service before ours manages to screw it up every week
I get the challenge of figuring out how to unfuck it 20 minutes before our service begins..

A few weeks ago, I walked in 15 minutes before the service and somone tells me we do not have sound...I turned and saw woman who had no clue about what she was doing with a fistfull of audio cables that she had pulled in her hand

Managed to get things working 1 minute before the service began
Link Posted: 10/11/2007 2:41:56 PM EST

Originally Posted By gene5:
run keyboards direct to snake if you can, sub your drum kit.set vocals and all instruments to "unity" or O on each channel,and get a GOOD outside EQ!!

We do have an outside EQ, and sometype of a programable reverb box that absolutely no one has any clue about

Explain your terminology...snake and Unity = ?

I never played in a rock band as a teenager
Link Posted: 10/11/2007 3:03:37 PM EST
[Last Edit: 10/11/2007 3:05:19 PM EST by pv74]

Originally Posted By starduks:

Originally Posted By pv74:

Originally Posted By gene5:
run keyboards direct to snake if you can, sub your drum kit.set vocals and all instruments to "unity" or O on each channel,and get a GOOD outside EQ!!

We do have an outside EQ, and sometype of a programable reverb box that absolutely no one has any clue about

Explain your terminology...snake and Unity = ?

I never played in a rock band as a teenager

snake is a big box that has like 20 3-pin connectors in it and a wire going all the way back to the soundbox.

god this is hs all over again. am i being tested?

edit for pic of snake


Yup....that's where we hook the mikes in...got it
I run the keybopard to a mike jack on the "snake" through that converter cable (TRS ballanced to XLR).
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