All told someone actually running the sound making needed adjustments based on the person speaking at a given moment is the solution, it’s why they call it “running sound”…
and I wanted to add but ran out of edit time…make the need adjustments when your HVAC kicks in.
Post a picture of the church sanctuary!!!
nah what are the hardware units?
Our speakers change faster than our volounteers can make adjustments.
Some of them slowly get louder and we can handle that.
But some of them emote constantly with way up and then way low.
No way we can adjust them in real time.
But why should we when electronics could do it automatically faster better .
@AH
Posted my answer two more times.
Neither appears here.
Bug in wordpress?
Sometimes it says I move too fast.
WTF?
Sometimes it just vanishes.
This message got the too fast message twice.
Hmm, your approach is still interesting for me. Let‘s recap
There are speaker with less or non existing speech training or microphone technique.
There are volunteers wit more or less experience in running a sound system, but they a in fact running the system
There is a HVAC which causes disturbing noise.
And there is a entry level mixer with entry level features and a mature firmware, which is not no bad designed for the indented users.
And guess, what is the only thing you try to change?
Training speaker needs approx 5 minutes each. I did this several times successfully with kids from the primary school or above.
Educating the volunteers is more complex but possible and highly recommended to avoid damage on people and things.
Repairing, tuning or replacing the HVAC or simply stop it during the ceremonies would be helpfull.
If the entry level mixer is not suitable it can be replaced by one which fulfill the needs.
But no, the only thing which is in your mind is to change the firmware.
Hmm, interesting.
BTW. My Experience over decades is that doing automatic level changes in a live system, especially when the situation is not well prepared before (good microphone practice, low background noise, perfect tuned sound system and so on) is very risky. Especially if you allow the automatic to raise the volumn will almost always cause feedback. Ok, I do not have articles or academic studies to prove that, only my experience.
@volounteer ,
Bug in wordpress? Sometimes it says I move too fast.
This is part of the anti-spamming, which can also block posts with certain content.
As you have managed to successfully post 6 messages with text only recently, were there links or images to the hardware units in the failed posts perhaps?
Please try listing them as text only, or send the list to me in a private message and I can check why they’re not posting.
Thanks,
Keith.
BTW. My Experience over decades is that doing automatic level changes in a live system, especially when the situation is not well prepared before (good microphone practice, low background noise, perfect tuned sound system and so on) is very risky. Especially if you allow the automatic to raise the volumn will almost always cause feedback. Ok, I do not have articles or academic studies to prove that, only my experience.
Spot on Mfk0815, as was the rest of your post!!!
Let me add that the problem in discussion here may result from someone reading too much
in conjunction with too little practical experience.
@Mike0815
The worst are guest speakers. No way we can train them.
The volounteers all are capable of doing the job they are assigned.
They do not react as fast as an experienced pro and may think for a moment about where the button or fader is they need.
The HVAC makes noise. It is not disturbing. But it does drive the proper SPL levels for max intelligibility of speakers.
I computed the levels based on background noise level and other factors I found in a technical paper on the topic.
The result based on all the input parameters was an average SPL and a DR maximum.
I would not call Qu32 entry level. What I have at home is entry level.
The old 8 channel Behringer at a previous church might be entry level.
I am trying to change what the audience cares about. Hearing the speaker with maximum intelligibility.
We do try to educate the volounteers. But some of them have many years experience and really are good if they aren’t sleepy:)
Nobody is assigned to anything that is beyond their ability. Our problem is not the volounteers.
HVAC is in good repair. It runs on automatic to control temp as needed based on crowd and ambient outdoors.
If you want to buy us a better mixer then let me thank you in advance. Else realise that budgets constrain churches a lot.
I never said to change the firmware. I suggested a change to make the device better based on what I have researched.
I really dont think the Qu will be changed. But maybe AH would improve the next generation with the change.
Dont know what automatic level approach you used. But lowering peaks while raising low sounds can never cause feedback.
Experience is what people did. By and large the world is full of stupid people who do dumb things.
When they make mistakes some of them change what they do and try something else.
The following text and links are posted on behalf of @volounteer -
"
Order of EQ https://www.izotope.com/en/learn/6-parallel-compression-mistakes-in-mixing.html
look at #3 – the others are good advice too
With normal EQ, or EQ’ing after a compressor, all of the unaffected frequencies are anchored while you change the level of the frequencies affected. EQ’ing the predominant frequencies before a compressor has the effect of anchoring those frequencies you’re changing while adjusting the levels of all other frequencies.
see item #6
Most modern mixing plugins, have a Mix / Dry knob on them. This is a ratio that allows you to set up the effect you want and then say ”I only want 80% of the effected version of the track while keeping 20% of the original dry version.”
That may be true , but also others with experience not knowing the true situation and applying their answer
without fully knowing all the factoids and thinking we are doing things they way they would have done it not realizing the difference. I also note that a number of experts apparently did not know about parallel compression before this discussion.
It is also due to some who assUME that we are doing what they would do if they fixed the problem and not realizing that our solution can never cause feedback. If someone has any evidence other than experience I have not seen it.
But lowering peaks while raising low sounds can never cause feedback.
I’m sorry, but what drives feedback? exactly this…
so upward compression is no solution for speach and it will not be in the next years
upward compression is bringing up low level signals, so if the speaker is making a break, the upward compressor will raise the level way to much… feedback
that simple and thats why it is not usable in most live scenarios
it’s good on some problematic sounds in studio environments but not if a PA system and microphones in one room are involved…
and parrallel compression is not the same as upward compression
even Wikipedia knows that (ok a lot of HipHop “producers” from the US mix this in a lot of sources together)
and I’m still waiting for the hardware upward compressors
I also note that a number of experts apparently did not know about parallel compression before this discussion.
I would say that statement is wrong!
It’s used more in the studio world that live, the SQ can do parallel out of the box.
@SteffenR
I think you are confused about something.
You will need to do more than assert your claims.
Show it to me mathematically while explaining it like a textbook would.
There is no way raising an spl levels of under 40 to 55dB to 60
while lowering the spl levels above 75dB down to 65 (or less down t6 60)
that feedback could occur when the original signal above 75 including
way above to 85 and more could cause feedback.
The only way to get feedback after regular down compression is to add makeup gain
which could do it. But we are not adding gain to make the signal higher.
We are compressing the loud stuff down while up compressing the low stuff up
but which is all still way lower than the now lowered loud stuff was.
You seem to not understand what upwards compression does.
Upward compression, works from the opposite end of the spectrum: when a quiet signal falls below a predetermined threshold, it’s brought up in level. … The dynamic range has been compacted—just like in regular old compression.
another site says for Vocals that vary too much in dynamics:
Sometimes you have too much dynamic range. Usually, we make the louder stuff quiet—but what if the vocalist is appropriately loud most of the time, but too quiet on various words?
This is a case for upwards compression—use it to bring the quieter bits of the vocal UP in level.
see the chart at
https://soundphysics.files.wordpress DOT com/2016/12/upwards-compression-comparison.png
wordpress wont let me post an url so you will have to combine the above
We would be in between those two diagrams.
Our highs would come down while our lows come up to lessen DR and maximize intelligibility.
Clearly no way for it to cause feedback.
Our highs would come down while our lows come up to lessen DR and maximize intelligibility. Clearly no way for it to cause feedback.
Use what you already have…
Bring up the mic channel gain a fader level to the level needed for the soft speaking
people, give yourself a little room on the channel gain for the loud talkers.
For the loud talkers find the compressor threshold that clamps them down and yet does not touch the soft spoken people, try a 4 or 5 to 1 ratio and a longer release time so the comp does not pump.
@volunteer
maybe we have to explain you the world of live audio again. Feedback has nothing to do with SPL or how loud the speaker is talking. It only is related to the microphone, the loudspeakers, their position relation to each other and the gain of the signal (not the signal strength or SPL). You know for sure that if you increase the overall gain of the mic it will cause feedback also if nobody is talking into it. There is a certain amount of gain you are not allow to reach, the gain before feedback. Otherwise you will cause that feedback.
So what increases the overall gain? first of all the input gain, then also, of course, the channel level and the main level (positions of the related fader). Also the EQ can increase the gain on some bands, the the make up gain of a compressor can increase the overall gain. and, now it comes, you say
Upward compression, works from the opposite end of the spectrum: when a quiet signal falls below a predetermined threshold, it’s brought up in level. …it’s brought up in level is just another way to in increase the overall gain of the signal. So any, A N Y, process which increases the overall gain can cause feedback, no matter how much SPL the signal has. And that's also the reason why we train the speakers to speak as loud as possible and not to speak inn a great range of loudness. if the input signal is very loud, you do not need to increase the overall gain so much to make that signal good hearable. If the signal is soft you increase the overall gain, and that cause feedback.
Mfk0815
Unfortunately we know nothing about the rest of the system in question, make, models, how it’s been set up and aligned/rung out…if at all or even a general picture to get an idea of what he is working with.
I have asked many times.
Mike C,
The details are not relevant because they only change the possible gain value by some decibels. But any value of gain before feedback is the border you are not allow to pass. It is like the comparsion of a car with or without ABS. No matter wich car you use, there is one speed which will cause that you hit the wall. You cannot beat the physic. Hmm
@volounteer
The worst are guest speakers. No way we can train them.Hmm, they arrive and then tell them „we have some diffucult audio situation. just some simple rules. Use normal voice and speak clearly. If you soften your voice reduce the distance to the microphone, if you soften your voice too much you won‘t be heard. If you speak louder than normal, increase the distance to the microphone. Don‘t point the microphone to your stomach, point it to the mouth, where the voice comes out. Do not mumble. If you obey those rules, everything will be fine, if not your message gets lost. And i believe that god gave you the intelligence to do it right.“ Not even in five minutes per speaker the „training“ is done. It worls for primary school children and it should for sure be possible for grown speakers.
On the mixing console EQ you can lower the lower frequency round about 200-300 Hz and use a high pass and feature a little bit around 2.5 kHz. Use a brickwall limiter to dame to high levels of the speaker but do not use any kind of makeup gain, hidden or not. Explain those simple rules to your volunteers.
Really should have read your post before I spent time composing a very similar one! 
You’ve obviously spent a lot of time reading up on compression techniques, but you need to pay attention to which of them are best used in live sound, and which are only really suitable useful in a recording/post production situation.
I really think you need to read up on acoustic feedback too, as you seem to have got some strange ideas about what causes it. As mentioned above, it’s to do with the overall system gain, not the volume - though a system that’s just on the edge in a quiet room, can often be tipped over by a loud noise.
As you don’t seem to want to believe the folk on here, try this for starters (retype the link):
geoffthegreygeek DOT COM /understanding-acoustic-feedback/
paying particular attention to the Microphone Gain section.
The details are not relevant because they only change the possible gain value by some decibels. But any value of gain before feedback is the border you are not allow to pass. It is like the comparsion of a car with or without ABS. No matter wich car you use, there is one speed which will cause that you hit the wall. You cannot beat the physic. Hmm
True but I would like to see a bigger picture of what he’s dealing and working with, system, speaker placement, the room, ect. Those factors all add up into the amount of available or lack of gain before feedback.
