Live vocal processing causing extreme feedback

[abri]

Hey everyone!
So,here is my problem...I use live to process vocals on stage,i also run my guitar through Live and use it to launch clips and stuff...so, every bit of sound is coming out of my computer.
I use built in Live audio effects to process my vocals, the problem is that no matter what i do to prevent feedback (i have tried EQing trouble frequencies, limiting, gating, low level in monitors, no monitors at all, and every other thing you could possibly imagine to prevent feedback from happening)it keeps on happening,even when i run vocals flat through live this happens,sometimes i run the mic direct to the PA system, and have no feedback at all, the moment i run it through Live even if it is flat with no effects at all, feedback starts happening even if everything is at the same level that in the previous test running it directly thorugh the PA mixer, so i was wondering why is that happening, is there something going on in Live that causes it to be more susceptible to produce feedback... i have tried everything possible except external feedback suppression, and still i get excesive feedback even when running vocals through Live flat.
Any help would be really apreciated!! thanks!!!

[Pasha]

Do you process vocals directly or through send returns?

[abri]

i process vocals both ways, and i get feedback anyway...but i even get feedback with unprocessed vocals

[SubFunk]

can you elaborate in very detail your entire signal flow...

from the mic, how exactly you go into which soundcard?, etc. (including routing you might apply within the soundcard, if your soundcard has a separate mixer section, maybe the issue is there, some soundcards have a monitoring option that can in combination with live's settings cause an internal loop)

because it doesn't sound from your description like it's a loop caused by mic / pa / pa / mic

[jonathan harker]

try to switch the input monitoring knob in live from auto to off.

[3dot...]

... beware of compressors

[abri]

... beware of compressors

yep, ive noticed how compressors increases the possibilities of feedback ocurring, so i have eliminated them from any channel reciving incoming signal from the mic...thanks

[abri]

can you elaborate in very detail your entire signal flow...

from the mic, how exactly you go into which soundcard?, etc. (including routing you might apply within the soundcard, if your soundcard has a separate mixer section, maybe the issue is there, some soundcards have a monitoring option that can in combination with live's settings cause an internal loop)

because it doesn't sound from your description like it's a loop caused by mic / pa / pa / mic

The vocal signal is going in through a Shure SM57 microphone, then going in to input 1 of a Native Instruments Guitar Rig Session I/O interface, it only has 2 inputs and 2 outputs,the it goes straight to a channel in Live with no extra routing, i just select audio from input 1,(i have multiple channels receiving input signal from the same mic, but they are never active at the same time, i have them mapped to a midi controller so they are open just when i am using them, one at a time) also the soundcard does not have any additional mixer section,sometimes i run the effects directly in the channel and sometimes via sends and returns, both ways i always get feedback...then the output of the channel is going to the master channel, which always has a limiter on it,then the outputs 1 and 2 of the interface goes in to a channel of the PA mixer, the channel on the PA mixer is running flat, no EQ, no compression, then it goes out to the speakers of the venue, and also to the monitoring system(which sometimes we leave off and still have feedback just from the sound coming form the venue speakers), i think that is the complete siganl flow... any ideas so far?

[3dot...]

this is just for your mic ? ...
maybe try cutting some offending resonant frequencies with the eq...
if that don't work try eliminating guitar rig... (you sure there's no compressor in your guitar rig presets as well?)

[abri]

this is just for your mic ? ...
maybe try cutting some offending resonant frequencies with the eq...
if that don't work try eliminating guitar rig... (you sure there's no compressor in your guitar rig presets as well?)

i have tried cutting the frequencies with the EQ, i have tried it in the master channel with Live's EQ, in the vocal channel, and also trying to eliminate the problem frequencies with a graphic EQ in the monitor mix, and nope, feedback is still there, and this has happened in many different venues... and about guitar rig, i just use it for my guitar which runs directly to the input of my interface, i dont process any vocals with guitar rig...i have tried nearly everything that comes to mind and no, the only way i have managed to eliminate feedback is just not running the mic through live, even with no effects at all, running the mic through Live seems to trigger the feedbacks

[Markemark]

I would start by connecting only your mic to your interface, and one track in ableton with just that input from your mic. Any feedback?? I think your problem could be the guitar rig plugin. I had a problem with crosstalk/bleed from input and output channels when using high gain amp sims. Anything coming from the output was slighting being feed to the inputs and with the high gain on the amp it was very noticeable in the mix when amplified. Your case could be totally different since I wasn't necessarily getting feedback.

[SubFunk]

I would start by connecting only your mic to your interface, and one track in ableton with just that input from your mic. Any feedback?? I think your problem could be the guitar rig plugin. I had a problem with crosstalk/bleed from input and output channels when using high gain amp sims. Anything coming from the output was slighting being feed to the inputs and with the high gain on the amp it was very noticeable in the mix when amplified. Your case could be totally different since I wasn't necessarily getting feedback.

what he says, after your description i would go step by step adding towards your setup you run right now... and try to pinpoint that way.

[abri]

I would start by connecting only your mic to your interface, and one track in ableton with just that input from your mic. Any feedback?? I think your problem could be the guitar rig plugin. I had a problem with crosstalk/bleed from input and output channels when using high gain amp sims. Anything coming from the output was slighting being feed to the inputs and with the high gain on the amp it was very noticeable in the mix when amplified. Your case could be totally different since I wasn't necessarily getting feedback.

what he says, after your description i would go step by step adding towards your setup you run right now... and try to pinpoint that way.

Yep, thats what iam probably going to need to do, cause nothing else seems to work...im going to start building my sets from scratch...i will let you know what happens next time i play live, thanks for all the help!!

[Markemark]

Ok so all you guitar rig plugin guys try this. You can check this with just standalone mode. Load up a high gain amp then for instance a spring reverb, now turn on the ni metronome. Hear the metro getting processed by the reverb? This is because your sound cards output is being bleed/crosstalk back to your inputs which is then going into your high gain amp and then reverb. You can also try recording without playing you will hear your metro or anything for that matter going to the outputs recorded slightly. I checked this on an old imac g4's built in sound. Now higher quality cards with have a higher noise floor and less crosstalk/bleed. I think the only way to have a live setup in which you use your guitar using these plugins and want to play backing tracks as well clean, you have to have the guitar inputs on a second sound card.

[3dot...]

^^^
yeah but I don't think that a slight crosstalk will cause extreme feedbacks
almost all venue mixers sport some crosstalk