Advice wanted on microphones and audio stuff for hall

[mikeprice]

Hi all

 

In my school - and I suspect many others - we have a sound system in the hall that is not used to its full capacity. It is currently connected to a PC and it is used in assemblies etc - and in some cases the more adventurous teachers will unplug the sound cable and plug it into an iPad/iPhone etc to play something or other (nad occaisionally they even plug it back in after!!!)

 

However, the hall is used to loads of other stuff - including 'celebration Assemblies' performances etc which sometimes use microphone. These then rely on the Deputy Head bringing in his guitar amp and hooking it up to them. We have a variety of wireless microphones and headsets and receivers - most of which are put away after still switched on which - for some reason that teh PTA and teachers can't fathom - means tha they don't work next time

 

SO

 

I was thinking

 

a better solution would be to have microphone continually ready to go - i.e. rechargable - and to have a system where multiple 'things' are plugged into the audio Amp and can be used VERY easily with nothing needing to be unplugged - and preferably the PC and microphone should woulk at the same time!

 

I THINK this means I need a simple mixer - am I right??

 

any help, ideas would be grateful - and if I talking rubbish and need a different solution please tell me

 

TIA

 

Mike

[Andrew_C]

Simple mixer - yes. Cheap mixer - no.

 

From your description of users skill levels, the best route would be an automated "conference" type rack mount mixer. In a locked cupboard, with a Rottweiler chained to the door. Sure did one, or maybe the Australian Monitor Company. The sort of thing I'm thinking of will feed a couple of stereo sources to the amp, and when a microphone channel detects a strong enough signal, will fade other sources out. Many different levels of priority can be programmed.

[nicholab]

Or a behiringer core x32 seems a solution.

[mikeprice]

In a locked cupboard, with a Rottweiler chained to the door. .

 

I see you have met users like my lot!!

 

p.s. thanks for the info

[VeryPC_Anthony_L]

Simple mixer - yes. Cheap mixer - no.

The sort of thing I'm thinking of will feed a couple of stereo sources to the amp, and when a microphone channel detects a strong enough signal, will fade other sources out. Many different levels of priority can be programmed.

 

 

Sounds like your thinking of a Dan Dugan type mixer. There are various systems like this from firms like Shure the only issue with these is that they have not eq and are aimed at microphones.

[mjs_mjs]

Or a behiringer core x32 seems a solution.

 

The x32 core might be perfect for many - for input channels you'll want gates and compressors, and you'll need to know about gain structure. Allen and heath did some smaller 1u rack mount mixers, or matrixes that would have been perfect for this type of thing. Soundcraft also have some cheap offerings packed with features. (Soundcraft Ui12 - Thomann UK)

 

Gates are like auto switches, when set up correctly, they can MUTE a channel if there is no audio coming through. if you get the threshold and release times correct, they can be a life save. For pc audio and other fixed gain channels, set the threshold to -30db of the nominal sound and the hold and release time to 5sec to start with. As fast an attack as possible. For vocal channels it's more complicated. You want it gate out background noise but be high enough so that the little girl with the weak voice will open the gate.... it's a tricky point to find (if it's possible) for a set and forget situation. if you have a mute switch on the microphone (or a squelch on a radio mic) then set the threshold as low as possible. Set the hold time to a few (maybe 3) seconds and the release time to 3secs as a starting position. The mixer will show you when the gate is open, holding and when it's releasing, so you'll be able to work out what needs changing. Also, you'll know the threshold point is too high if they sound like they are getting cut off and interrupted while talking. If you're lucky enough to have a side chain, set the hipass to 160 and the lopass to 2k to start with.

 

Compressors are like limiters, and for the purposes of this treat them the same. Set the threshold to the point you define to be loud enough for PC/line, with an infinite ratio, super fast attach and a release of 40ms. play one of your favourite tracks if it sounds like the volume is pumping then the settings are wrong and try again. For audio it's tricky to get a one size fits all, but get your head or someone to talk normally, and bring the threshold point down so they just enter into it - set the ratio to 6-8:1, fast attack, with a release of 10 times that. Then move the threshold up 3db. Now get them to talk normally and also to raise their voice. They should be able to talk normally without the compressor coming in, but when they raise their voice, it should go into compression. This limits the signal to the system from that mic input. again - if they sound pumping - go back and fiddle. If possible, get both male and female, tall, short, get someone from science who understands long complex words to give it ago, as well as the loud and quiet members of staff....

 

They're are many youtube video's on how to do gain structure.

 

If you have a graphic and time, grab a laptop, install 'Room EQ Wizzard' and find the room resonances and feedback points and remove these in either a house graphic or the mics parametric(s). To be honest, this kind of system tuning is done alot better by an audio engineer...

 

in reply to the original post - Sennheiser do some rechargeable mic's which are half decent for this kind of thing, (i used to look after them while i was at a uni (as tech staff)).

[Chris_]

I'd recommend looking at the Sennheiser EW100 G3 range of wireless microphones as you can buy rechargable accessories for them to allow them to be charged without having to remove batteries etc.. just relies on them being put back in the chargers after use!!

[VeryPC_Anthony_L]

I don't often seee the X32 get mentioned one here @nicholab

Although a good idea by the time you add a stage box it becomes quite expensive...

 

Never also seen anyone suggest to run Room EQ wizard either @mjs_mjs

Prob overkill for most IT techs but is useful if you want to tune a system. You would need to get a measurement mic and a usb soundcard. Personally I like using Tuning capture (WaveCapture) but this is not a free program but is very good.

@mikeprice when you say a variety of mics, how many do you mean as this would be an important factor as to how many channels you need. I guess the question is what do you want to achieve on a daily basis and what do you want do you need to do longer term.

 

 

On the rechargeable aspect could you get the teachers to change the batteries and put them on charge. if you have higher end mics that show battery level then this would help knowing when they need changing.

[mikeprice]

Hummmm

 

Basically I want a couple (no more than 2) mics to be available to just pick up and use - assuming that the 'mixer' (or whatever) hasn't been fiddled with. They would then just work along with any sound that is coming from the pc

 

anything more complicated would freak my lot out

 

more complicated adjustments such and changing the volume of different channel would be great on special occasions as I would be around to operate it - and I am sure I would be able to manage (!!) - although I do have a couple of TAs that would be able to with a bit of confidence and experience

 

 

rechargeable batteries sound like a good idea - but batteries seem to get eaten around here - just like teaspoons in the staff room - teachers are weird

[Andrew_C]

I'd start here, really, I would. http://www.canford.co.uk/Products/2016169/93-546_SHURE-SCM262E-MIXER-Stereo-2x-microphone-3x-stereo-inputs

 

Oh, and the Rotti!

Edited March 29, 2016 by Andrew_C

[VeryPC_Anthony_L]

The Shure units are nice albeit a bit pricey I always feel. These are well priced a a popular unit ART Pro Audio

[Andrew_C]

But no automation...

[VeryPC_Anthony_L]

But no automation...

 

The Art as you pointed out does not have automation but then the Shure automation is more to do with the stereo channels and how the mics work with them.

[Andrew_C]

Yes. Duck the line level inputs when a user speaks into the mic. No user fiddling.

[VeryPC_Anthony_L]

but its not a true automixer. The automixer function is designed as a paging system. A true automixing system is the Dan Dugan systems that mix the microphones together. Dugan Automatic Microphone Mixers

[Andrew_C]

But THAT is way beyond what is needed. As I read the op, it is a basic set and forget needed. Sounds from a PC, scope to plug in an iSomething, and a couple of mics.

I'm suggesting adding auto-duck on at least one of the mics so when the Head or whoever talks, the music fades out, without an operator.

[VeryPC_Anthony_L]

Oh yeah a Dan Dugan is overkill but the op sounds like he wants the mics to mute. Another way to do this would be to use a Gate/compressor on the mic channels. This would mean that when there was no signal / low signal the mic would be muted as such.

[mikeprice]

Oh yeah a Dan Dugan is overkill but the op sounds like he wants the mics to mute. Another way to do this would be to use a Gate/compressor on the mic channels. This would mean that when there was no signal / low signal the mic would be muted as such.

 

I have no idea what that means????

 

BTW

 

thanks to everyone for the responses - I think I know what to research over the easter/Spring hols - or whatever they are called

[PotNoodleTech]

Blimey so people are recommending £3000 autofaders, room EQ and all sorts, sounds like all you really need is a simple, basic, reliable mixing desk. They come in standalone or rack mount formats.

 

I am a big fan of the Allen & Heath Zed standalone series.

 

I use a 24 channel one similar to this for £500: Allen & Heath ZED-22FX 22-Channel Series Live Mixer With USB I/O And DSP Effects | DV247

 

But realistically you could get away with a 12 channel one without effects by the sound of it. Cheap and reliable: Allen & Heath ZED-10 | DV247

 

That way like I do, always have two stand Mic's plugged in which can be used any time and are always on, the PC input is always on and an aux input is always on for a CD player. If there are any events going on they tell me and I plug in more MIC's etc.

 

We've had full bands and choirs in and they compliment on the good sound - only using cheap(ish) warfedale 12" speakers (x6) a wharfedale 15" sub (x1) and a couple of rack mount amps and a DBX Driverack as a crossover for a bit of room EQ. None of it outlandish. Basic, reliable.

 

you may need to get some cabling run to various points in the hall for Mic's etc - it shouldn't cost too much, few hundred bucks.

 

No need to spend £3k or go on a 3 year degree course to work out how to use it.

Edited March 31, 2016 by PotNoodleTech

[mikeprice]

Thanks

 

Yup - what I am after is simple and cheap - if I put in something with loads of knobs and dials they will freak

 

I was really after something very basic - several input all mixed to the amp - and a volume control for each input - nothing else really

 

nothing clever or complicated

[VeryPC_Anthony_L]

Blimey so people are recommending £3000 autofaders, room EQ and all sorts, sounds like all you really need is a simple, basic, reliable mixing desk. They come in standalone or rack mount formats.

 

Hands up, I did mention the Dan Dugan, but more from what it offer which is auto mixing of mics etc, but will never expect a school to buy one as they are VERY expensive.

Room tuning can be helpful if you had a distributed PA along with time alignment. It might sound overkill but if you have a distrubuted pa system them would always suggest getting a speaker management unit to level it and set time delay.

@mikeprice Having read what you want I feel the Art MX622 would suit your needs (ART Pro Audio). If you are doing a bigger show then a proper sound mixer would be advisable but for day to day use the ART would work well and is VERY simple to use and reasonably priced.

[mjs_mjs]

Never also seen anyone suggest to run Room EQ wizard either @mjs_mjs

 

I would use SMAART personally, but you can guess my background is not just IT...

[VeryPC_Anthony_L]

I would use SMAART personally, but you can guess my background is not just IT...

 

SMAART is good although expensive, Tuning capture is what I have been using more recently and preforms really well. I know quite a a few people who use and is really good.

You might be able to guess that I am not just IT as well......

Oh how I would love to be able to sale a Digico console or even a Midas Pro console to a school............

[mjs_mjs]

Oh how I would love to be able to sale a Digico console or even a Midas Pro console to a school............

 

I have, had a gig with a Pro2c in a school, for the school... was way overkill!

[VeryPC_Anthony_L]

The biggest i have used in a School environment is a GLD80 and the students loved it. I took my Avo Tiger touch 2 that I owned at the time in quiet a bit and they LOVED it.