Mono question - Yamaha stereo mixer

[bzb]

I've been running the Yamaha MG124C board without the ability to cut the mics from the subwoofers. I'm running the entire system in psuedo mono (stereo from the board, Y at the XTi).

I'm thinking now of running it mono from the board, by moving all my Pan knobs to the L. Run the Stereo Out L to the right side of the amp (tops) and the Group 1-2 L output (which is 1/4") to the left side of the amp (subs).

Then I can just drop the mics from Group 1-2, and my other sources are both Group and Stereo...

What do you pros think of this idea? Other than losing the dB boost I get from running Group into Stereo, are there any other detractors I'm skipping over?

Here's a pic of my board, if it helps.
http://www.yamaha-europe.com/picture_ar ... gh_jpg.jpg

[Bruce Weldy]

while I'm not sure why you want to do this.....you can start by hitting the 80hz roll off switch. I couldn't tell if your board has one, my Yamaha does.

secondly, the easiest way to do this is to use the Aux send to feed the sub side of your sound. Then only the channels that you want in the subs get turned up. This is how a lot of big sound companies run their subs.

[bzb]

while I'm not sure why you want to do this.....you can start by hitting the 80hz roll off switch. I couldn't tell if your board has one, my Yamaha does.

secondly, the easiest way to do this is to use the Aux send to feed the sub side of your sound. Then only the channels that you want in the subs get turned up. This is how a lot of big sound companies run their subs.

Yeah, I tried that, but I'm crossing over at 100Hz now. I think that, combined with the rising response of the Titans, is what's causing my issues. Any "P"s or "F"s are really annoying

Aux is interesting... but how would I run that then? I didn't think you could just Y-cable your outputs together to run them mono. Wouldn't I still have to cut the Pan knobs to "L"?

[Tom Smit]

Whatever you want to go to the subs is what you rotate the aux knob on (on the channel strip). Then send aux out/send to the channel on your sub amp (xti). So, in your case, the vox don't have the aux knob turned past zero on their strips.

[Fish]

Yeah, I tried that [80 Hz roll-off], but I'm crossing over at 100Hz now. I think that, combined with the rising response of the Titans, is what's causing my issues. Any "P"s or "F"s are really annoying

Aux is interesting... but how would I run that then? I didn't think you could just Y-cable your outputs together to run them mono. Wouldn't I still have to cut the Pan knobs to "L"?

A quick check of the manual says that the aux sends on stereo channels are summed together for the aux busses. So run the channel pans and the output of the console as you normally do to the amp(s) for your tops and connect the sub amp from the Aux 2 output. (This way the send is always post-fader.) Only turn up the aux send for inputs that you want to go to the subs; leave the aux send of the mic channel(s) off and those signals will NEVER get to the subs.

Ideally you'd want to set up the gain structure so that any channel's sub aux send is either on to the nominal mark (the triangle/arrow) or off completely. That way your entire system tuning isn't completely thrown out the door. I'm not sure I've been able to make that work so well in my reality, though, so don't kill yourself if you find yourself mixing the sub level differently for different inputs.

Hope this helps and clarifies.

[wallywally]

BZB... the way you described will work, and possibly best for your situation. I run aux fed subs and prefer it because I can control the sub level from the board. The downside to this is that the aux master isn't tied to the main master slider(on my 01v) and I often forget to turn down the aux (sub). Do some reading on aux fed subs.

[bzb]

Sorry - should have clarified. I realize how the Aux works, and running it mono isn't a problem since it's going to subs. What I meant was, wouldn't I still have to run the tops in mono using the Pan Left?

Thanks for everyone's inputs. Now I have a couple of options to try!

[Fish]

wouldn't I still have to run the tops in mono using the Pan Left?

Short answer: no.

Longer answer: if you use the mixer's stereo channels with stereo sources for prerecorded music playback, you'll want to use both of the stereo outputs from the mixer or you'll completely lose one side of the source. (It's actually a balance control, not a pan, for stereo inputs and the right input will never reach the left output no matter what you do.) Normally this isn't that big a deal, but there can be just enough effects or sounds on one side of a track or the other that someone could notice something missing. The first example that comes to my mind is Queen's Bohemian Rhapsody. If you don't/won't/can't use both of the stereo outputs of the mixer, just use each input channel as a single mono input, with two faders per stereo source; or use a passive mixer to connect a stereo source to the mono input jack (see Rane's "Why Not Wye?" tech note for more on... why).

For a live band, the mix is probably going to be mono or so close to it that it doesn't matter. Just use one main output from the mixer and go on with life. You won't be missing a thing, and you'll still have both sides of your headphones usable.

[bzb]

Ah, gotcha. Thanks. So, as a DJ, I'm probably not going to be able to do this since I have to sum it at the amp - or get an external DSP...

Otherwise, I'm forced to use Traktor only, as I have no way of running a summed mono signal from Serato or MixVibes.

[Fish]

Ah, gotcha. Thanks. So, as a DJ, I'm probably not going to be able to do this since I have to sum it at the amp - or get an external DSP...

So you're already using all the available channels on the mixer?

Wait a sec, are you currently using the Y-cable to "combine" the stereo output of the mixer, or are you using it to send one of the mixer outputs to both channels on the amp?

If you're "combining," continue to do so (but only until you build a passive summing network like in the Rane Note ) to combine the left and right outputs of the mixer in to the left (top) amp channel. Send the aux to channel one (sub) of your amp. Done!

If you've been using it to split one output of the mixer to both amp channel inputs, then you've already been missing one side of the mixer's stereo output. Remove the Y-cable and connect as above.


If that makes sense, I think that would get you going.

[bzb]

Doh, just saw this. I'm going to have to experiment some. Thanks for all the ideas!

I finished up the last coat of Duratex on the new T39 just now... so I'll be out in the garage tomorrow night playing around (and recording video, hopefully!)