oove Posted August 5, 2014 Share Posted August 5, 2014 Hi again, usually the FBS reduce the gain (?) of the channel if you produce a feedback and after that all is like before. (?)Today i had a bad feedback and the FBS was not able to kill it. But that is not the problem. My problem is a complete changed channel - a drastic reduced volume without being able to see it on the Settings. I checked the red trim ... it looks like before, the meter is moving around 100%, the setting is the same. Ã checked the green gain ... it looks like before, the meter is around 100%, the setting is the same.But i hear only 25% of the volume.All other channels are ok.My question, is there a place where i can check, what the FBS did? It is important to understand it, because i wrote 60 scenes, and i would have to change all 60 scenes if i cannot find the general setting. Quote Link to comment Share on other sites More sharing options...
ArneLine6 Posted August 5, 2014 Share Posted August 5, 2014 The FBS uses very narrow notch filters that are usually not audible. In extreme cases of severe feedback the gain gets reduced as a last resort. The settings are not stored with setups or scenes. If the FBS is resorting to reducing the gain that means that there is a severe problem on stage. Most likely the stage is way to loud, a microphone is right in front of a speaker, limiters and compressors are too extreme or similar. Quote Link to comment Share on other sites More sharing options...
oove Posted August 5, 2014 Author Share Posted August 5, 2014 Thank you for that very fast replay! Assuming that the feedback problem is solved by reducing the master gain. Where can I see what the FBS did and how to get the old setting back?My trim and gain faders of that channel are in the same position and the meter indicates optimal Level, but i hear almost nothing of this mic.That means, all scenes of that setup are in wrong relations because the FBS changed that channel.What to do? Quote Link to comment Share on other sites More sharing options...
ArneLine6 Posted August 5, 2014 Share Posted August 5, 2014 The FBS happens on the input channels. If you go to Tweak- deep Tweak- Inputs you can see the settings and an FBS reset button. Quote Link to comment Share on other sites More sharing options...
ArneLine6 Posted August 5, 2014 Share Posted August 5, 2014 The scenes and setups are fine since the FBS parameters are not saved with the setup. Quote Link to comment Share on other sites More sharing options...
oove Posted August 5, 2014 Author Share Posted August 5, 2014 Here both setups: https://dl.dropboxusercontent.com/u/13754833/Klingenthal1.bin https://dl.dropboxusercontent.com/u/13754833/Klingenthal2.com channel 1 of the first setup is much stronger, but all visible faders have the same positions comparing setup 1 and 2. Quote Link to comment Share on other sites More sharing options...
oove Posted August 5, 2014 Author Share Posted August 5, 2014 Ouch - unfortunately i saved it. :huh: The FBS reset doesn't work. Quote Link to comment Share on other sites More sharing options...
ArneLine6 Posted August 5, 2014 Share Posted August 5, 2014 If the levels are different there can be many reasons: EQ's, compressor make up gains etc. You can disable the FBS and check this. Quote Link to comment Share on other sites More sharing options...
oove Posted August 5, 2014 Author Share Posted August 5, 2014 Yes of course. I checked it already.But I did nothing and suddenly (after the feedback) all settings remained unchanged, but the volume of mic 1 ist much lower - in all scenes of setup 2.If I compare, I cannot find any differences on EQ, Compressor etc.FBS reset has no effect. Tomorrow I will create all scenes new by saving the first setup as setup 2 and changing the scenes and only hope, that this not happened again. Quote Link to comment Share on other sites More sharing options...
danielolsen_4 Posted August 6, 2014 Share Posted August 6, 2014 Level problem is most likely faulty hardware Line 6 just wont admit it. 1 Quote Link to comment Share on other sites More sharing options...
oove Posted August 6, 2014 Author Share Posted August 6, 2014 No, i don't think so.I think there is a intelligent automatic control, and I cannot recognize and cannot reset it. Quote Link to comment Share on other sites More sharing options...
ArneLine6 Posted August 6, 2014 Share Posted August 6, 2014 I just looked at your setup and found that channel one in the setup "duo" has a trim (gain) of 0 while channel one in the setup "balla" has a gain of 31dB. There is no hidden automatic control. Even if the FBS turns down the gain you would see a red bar on top of the input tab in deep tweak mode that says "Emergency gain xdB" When resetting the FBS of loading a setup this would disappear. Maybe i have got the scenes you are referring to wrong but from here it looks like there is significantly different trim (gain) going on. 1 Quote Link to comment Share on other sites More sharing options...
oove Posted August 6, 2014 Author Share Posted August 6, 2014 Oh ... thank you for the look at my setup! The two setups to compare are duo1 and duo2. (balla is a completely different band ) I did not know that all setups are stored. Sorry for that confusion!Today I created the duo2 new and so far everything is ok. Your Information is helpful. But the best help would be, you comprehend the described situation in my duo1 and duo2 and have an explaination. duo2 is a copy of duo1 with the same trim setting and at least all "moduwe" scenes should also have the same gain fader settings and all eq/compressors etc. are the same. but in duo1 it is loud, in duo2 it is soft while the meter is showing loud. Quote Link to comment Share on other sites More sharing options...
EllisF5 Posted August 7, 2014 Share Posted August 7, 2014 I checked the red trim ... it looks like before, the meter is moving around 100%, the setting is the same. Ã checked the green gain ... it looks like before, the meter is around 100%, the setting is the same. But i hear only 25% of the volume. Slightly confused by one thing here. When you say the "meter is moving around 100%", are you saying you have both the channel trim and the channel gain both running on near maximum? If so, that is not optimum and is very likely to contibute to serious feedback problems, especially if you are running microphones through those channels. I would suggest doing some reading on 'Gain Staging' in PA applications. In brief, you should be looking for the absolute maximum peaks to read several dB below 100% on the meters - this will give you some headroom. Also, if you correctly balance the channel gain vs the master output you should not normally be running those channel gains at anywhere near maximum. Excessive gain applied to channels with mics is a prime cause of serious feedback issues. In addition, look at the pickup patterns of the mics, and make certain any stage monitors are in the most effective 'null' position. This is different for cardiod vs. hypercardiod microphones. Finally, overall stage levels are another common issue. Getting feedback under control requires an analytical approach to the entire system, and can involve everything from making sure the monitoring is OK, to how performers 'work' the mics. I would not try to use auto feedback suppresson to overcome other problems that might exist - it is a useful tool to have and works well (within limits), but it will not completely fix things if, say, your gain staging is completely off or if you have a monitor too loud and aimed into the pickup field of a sensitive mic. Quote Link to comment Share on other sites More sharing options...
oove Posted August 7, 2014 Author Share Posted August 7, 2014 Sorry for my bad english. The only thing i wanted to say is, that all visible settings are the same, before and after. Also the metering. I use mixers (also digital) almost daily for 20 years. I know headroom - and feedback issues, also with monitors. Originally I had a resonance and one usual method to find a resonance is to sweep the frequency with positiv eq qurve, not negative. That feedback was my intention. I forgot to turn off the FBS on all open mics in this moment, so that was my mistake. I found the resonance somewhat roughly, could decrease that range but now I have a messed channel and accidentally I saved that setup. The m20d is new for me and the buttons "save" and "load" are damn close together :D .That is not so bad, I would just like to understand. If really is a feedback on stage and i get a messed (strongly reduced) channel right in the gig, it is not fixed by increasing the gain back. 1. That would not be possible because both "knobs" (trim and gain) are optimal - (not 100% ... maybe 75%), both before and after the operation of the FBS.Please don't say, i could increase it from 75% to 100% because: The level after the trim is optimal (if i would increase the trim i would get an internal distortion). The level after the gain is optimal (green and a little bit yellow) (also i would get internal distortions). Nevertheless the audible level of that channel is significantly lower after the feedback. 2. If simple increasing of the channel would be possible, i had to do it for all 26 scenes seperatly. I am musician, I cannot do that during gig. Quote Link to comment Share on other sites More sharing options...
dboomer Posted August 8, 2014 Share Posted August 8, 2014 The feedback manager can only control feedback to a point. There are laws of physics that limit that. The feedback manager can allow you to operate at higher levels than the onset of feedback by notching offending frequencies. But once it has done a few (and it depends on many factors of your specific setup and venue) it can't really do anything else but reduce level to prevent feedback. Smoothing can only help so much, after that the reflections off your face into a mic or from the back wall become the dominant factors. And the feedback manager can do nothing about that. It is at this point you need to back your system down a bit as you have reached your limit. If you don't then it will appear to keep backing down your channel. But it's not really turning down your signal as much as it is holding that threshold constant and the rest of your system is coming up. Quote Link to comment Share on other sites More sharing options...
Digital-sound Posted August 17, 2014 Share Posted August 17, 2014 When everything is set right, and not trying to overdo it as mentioned, the feedback manager is great. I only ever hear a quick squeak now. If you need more out of your system, back off the effects. The drier the vocals, the more volume you can get if that is what you need. Reverb will work against you. Also, watch for reverb in the monitors if the feedback is on stage. It can easily appear on the monitors if you don't check that it is not linked. The effects start as global until you remove them. Quote Link to comment Share on other sites More sharing options...
oove Posted August 24, 2014 Author Share Posted August 24, 2014 Thank you. That question is not answered, but it is not a big issue. It was a amassment of mistakes and should not happen again. 1. I will no longer operate with 26 Scenes. So i could change the situation quickly with only 3 or 4 scenes.2. I will not save accidentally a messed channel. 3. I will switch off the FBS during Sound check experiments. Quote Link to comment Share on other sites More sharing options...
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