the new automatic microphone mixing feature

[lesouvage]

I have done some reading on the AMM feature that has been added to my Qu-16 mixer with firmware 1.8 to get more understanding of what it can be used for. I found https://www.yamahacommercialaudiosystems.com/downloads/manuals/interfaces/Automixer_WhitePaper_en.pdf which seems to be a useful paper to get understanding of what AMM actually is. (other pointers to relevant info are very welcome)

Gating Automatic Microphone Mixers (GAMM) and Gain Sharing Automatic Microphone Mixers (GSAMM) are mentioned in this paper.

From what I understand, with GAMM there always is just one mic in operation and as long as a speaker continue speaking the rest of the mics will be gated. This sounds like very useful for meetings that need some discipline of the participants.

With GSAMM the sum of the gain of all the mics will always be the same so an interruption will lower the volume of the one already speaking. This avoids feedback and/or very loud sound coming out of the speakers if a number of participants of a meeting/conference starts to talk at the same time.

What kind of AMM is added with the 1.8 firmware?

btw: I think it is great that, with every free update, more features are added to my Qu-16. Compliments for the A & H development team.

(Sorry, I should have posted this question on the general forum and not on the Qu trouble shooting forum EdW)

[David Haughton]

Hi lesouvage, thanks for the compliments!

Qu AMM uses the Qu ‘D-Classic’ constant gain sharing algorithm to dynamically adjust gain for each channel in proportion to its input level and priority setting.

Louder signals receive more gain in the mix while quieter ones receive less and the overall gain remains the same.

Mics set with higher priority get a larger share of the gain and when no one is speaking, gain sharing maintains background ambience.

There’s more info on pages 63-65 of the Qu Mixer Reference Guide here: https://www.allen-heath.com/media/Qu-Mixer-Reference-Guide-AP9372_8.pdf

There will also be a YouTube video tutorial on setting up Qu AMM available very shortly!

Let me know if you have any more questions.

[lesouvage]

Tonight I received a phonecall with a request to do the sound at a debating evening coming week. A good reason to test the AMM feature. I connected 5 mics and enabled the AMM feature on this channels. It seems to work all fine, when I used one of the mics I saw the level meters on the touch screen of the other channels going completely down. The devision of the total gain available between two channels wasn’t really visible but I assume that it will work OK. I tested it at my living room so I couldn’t pump up the volume to much.

But when none of the microphones is in use the touchscreen shows a gain volume on all the channels indicating that all the microphones will pick up ambience sound. Is this by purpose and what is the idea behind it? To me it feels more logical to have all the gains down when none of the microphones are in use.

A workaround to get all the gains of the microphones down is to add an extra channel with pink noise (or whatever constant sound) from my iPhone, enable the AMM feature on this extra channel and push the fader for L/R of this channel completely down. I gained this channel on a level that was just enough to get the AMM feature to work so the gains of all the mics were 0 as long as the mics were not used. This is working great. My question is if this workaround does make any sense or is it a solution for a non existing problem. Thanks in advance.

[lesouvage]

Just an extra question: is it possible to route pink noise generated by the Qu-16 into a channel (in my case channel 6) so I don’t need to connect an iPhone to the mixing table.

[Anonymous]

You can push it out of any output, so analogue into an input should be ok

[lesouvage]

UPDATE: I tried it out again today and it seems to work fine. I must have made a stupid mistake yesterday. Using the signal generator and connect the mix with the signal with a channel that is part of the AMM at a proper combination of volume of the mix/gain of the channel used (where it just turn of the other mics) seems to work fine.

[XAP]Bob, I tried connecting mix1 with channel 6 after turning on the signal generator and assign mix1 to it but it seems that I run into a problem. When I connect mix1 to channel6 their is a noise on channel 6 if I completely open the gain to the max but this sounds stays the same whatever I do. When I choose pink noise or white noise, and raise and lower de gain level of the signal generator and even when I mute the signal generator it doesn’t make any difference. The sound on channel 6 does what it is expected to do, turning down the AMM mics as long as they are not used, but I don’t understand why the signal generator doesn’t seem to work as expected.

I read the signal generator part in the manual, checked if Talkback was turned on and even changed the XLR cable used. Am I missing something or could something be broken with the signal generator? Thanks in advance.

[Lou]

When nobody is speaking the ambience equals the ambience when people are speaking, so you are seeing norml behaviour. No need for adding noise of any kind.

[lesouvage]

Lou, that makes sense although I remain curious about how it works with the use of the signal generator. With all the mics open picking up ambience sound it feels like there is a lot of ambience sound coming out of the speakers. I will use the feature tomorrow and the day after tomorrow and I will share my experiences.

[David Haughton]

Hi all, firstly ambience is most important in broadcast and recording applications, however it’s also important for smooth, natural sounding operation of AMM.

I have setup a test as you’ve described, and find if the sig gen input gain is too high, it reduces the gain of the mic channels too much so you don’t get optimal gain structure. Setting the sig gen input channel too low causes a similar effect to gating these mic channels. The threshold is not always reached meaning that audio doesn’t pass through and you hear ‘chopping’.

I will be doing a little more investigation over the next day or so and will let you know my findings.

Thanks.
Harry.

[lesouvage]

Harry, thanks for the effort of testing and investing time.

Erik

[lesouvage]

I had the AMM on and running tonight on 5 mics and I think it works perfectly. It was an evening with debate and a documentary on screen and discussion afterwards and I kept the mics open the whole time as a test and there was literally not a moment with a problem or feedback or a reason to adjust the sound. It was a small venue with around 35 attendees with 2 x-act sound projects speakers ( a Dutch high-end brand of active speakers). The software developers really did a good job which opens a complete new market for my sound servcices. Tonight it was a voluntary job but tomorrow I have a real gig at a debate evening. I’m full of confidence 🙂

[David Haughton]

Hi Erik, that’s fantastic. Thanks for the feedback (the good kind) and let us know how you get on tonight. 🙂

[Chase]

Hi [Harry @ A&H] you mentioned a tutorial video for setting this up. Any idea when this will be ready. I’m looking for a way to set up the AMM with a softkey so someone can simply walk in press a button and then run a simple Church service with 5-6 spoken mics in play. Thanks!

[Anonymous]

Hello,
Can anyone tell me if the auto mixing feature will work effectively with up to 7 omni lav mics, at times in close proximity in a round table discussion for a television program to minimise open ambience and comb filtering on lavs not being used? SO we get to as close as possible the sound of just one lav being ‘open’? ie, is it as good as a full dugan system?

Many thanks

[David Haughton]

@dalewillis Hi Dale, we haven’t tried AMM with omni lav mics here, but have used gooseneck condenser conference mics in a pretty “ringy” room, and found that the results were really impressive. AMM’s “D-Classic” algorithm worked as well as (if not better) than some expensive plugin solutions and even the “real” thing. It’s response time is so quick and natural. We have found that our AMM seems to like a hotter input signal than most and good EQing of the mics plus some tuning of the Sidechain Filter really helps, but certainly no more that would normally be required if I had 16 condenser mics open all at once! We’ve even had it working well with post fade monitor sends to individual conference speakers at the panellist positions open at the same time. Let us know if you need any more info. We’d be keen to hear back from you about the results (would be great to get some high quality pics too)! Drop me a message when you have it working. Thanks. Harry.

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