Diy rig for social distancing choir

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Actually I see no reason why that would not work. The drain bias voltages of the common-source stages will increase a bit, but that's all.
The buffer MOSFET in these mics acts more or less like a DC constant current source, with some AC modulation on it due to the microphone signal.

If you use a 44 ohm load instead of the specified 2200 ohms or so, you not only affect the DC bias voltage, you also reduce the AC output signal from each mic by a factor of 50...


-Gnobuddy
 
Really have to think out of the box here, to allow members to accomplish it and stay at home. Something like everyone calls in on their cell phone - ladies one number, gents another - then a radio station broadcasts the (stereo) mix back to FM radios at everyone's homes for monitoring.
Audio latency is the killer here. There's far too much latency through a cellphone link to allow singers to sing together in time.

I have been struggling with a similar problem, as our usual weekly jam group has been shut down while we all hide in our homes trying not to die. We now meet via video chat for our "jams", but the amount of audio latency is so high that they are no longer jams - it's completely impossible to play or sing along with each other.

Instead, the new format is what is sometimes called a song circle, where one person at a time sings and plays by herself / himself, and the others can only watch and listen, but not participate.

It's better than nothing, but it is a very poor substitute for the joy of actually making music together.

I expect people who enjoy choir-singing feel exactly the same way. Sure, you can sing alone, and that can be enjoyable, but it is a very poor substitute for the magic that happens when the voices of an entire choir blend together and create something vastly richer and more complex than one voice by itself.


-Gnobuddy
 
Off topic: does anyone understand why the distancing rules are very different depending on what country you are in? Here in the Netherlands the official number is 1.5 m, wherever Felix may be located it is 6 ft = 1.8288 m, for Dave it is 2 m and in France a mere 1 m will do.

Yeah, I understand why - nobody really knows what the best value is, other than "infinity". So they pick a reasonable one their country's people can best understand.

These onesy twosy meter values might be OK - BUT under specific conditions. Such as time of exposure; how long you need to remain within an enclosed space at such distances. Or whether people are talking / singing / shouting out protests - or just breathing normally during a sedentary level of activity.

My personal criteria - which I'm very lucky to be able to even do - is zero contact with anyone outside my immediate household. If I need to go inside an enclosed space where other people are, I use waay-overkill PPE - the very best front line ER level emulating contraption I can muster up. I simply cant trust anyone else to regard my ongoing physical health as something valuable - fairly probable just one simply wont - so that's entirely up to me.

Challenge accepted.
 
The buffer MOSFET in these mics acts more or less like a DC constant current source, with some AC modulation on it due to the microphone signal.

If you use a 44 ohm load instead of the specified 2200 ohms or so, you not only affect the DC bias voltage, you also reduce the AC output signal from each mic by a factor of 50...


-Gnobuddy

Indeed, hence my post #21. I don't think it would be a big deal to include a couple of resistors and a switch, though - there is no need for the resistance to be precisely 2200 ohm/n.

I think the issue brought up in posts #9 and #10 may be a bigger problem. If you want people to hear their own voice stronger than those of the rest without having to slide one side of the headphones of their ear, you can't use paralleled microphones, nor a common amplifier to drive all headphones.
 
I think the issue brought up in posts #9 and #10 may be a bigger problem.
I think we can agree that there are quite a lot of difficult issues to deal with. :)

While the engineering side of my brain wants to hunt for technical solutions, the emotionally wiser side of my brain says that J.M. Fahey is right. There is no reasonably safe solution to the problem as originally posed - and it is just not worth risking people's lives in order to be able to sing together in the same room.

It stinks that so many of us are being robbed of so many of the things we enjoy, but most of us would agree that we'd much rather be alive and feeling a little deprived, than wheezing ourselves painfully to death with lungs ravaged by Covid-19. :(

Anyone know how to make a string telephone with fifty Dixie cups and a ball of thread? Maybe that's the answer. There's no perceptible latency, and you can make the strings long enough so every singer is 10 metres (about 33 feet) apart. Everybody stands out in a soccer-field while singing. :D


-Gnobuddy
 
While the engineering side of my brain wants to hunt for technical solutions, the emotionally wiser side of my brain says that J.M. Fahey is right. There is no reasonably safe solution to the problem as originally posed - and it is just not worth risking people's lives in order to be able to sing together in the same room.

I don't know about that. Nothing is ever perfectly safe, but whether it will be reasonably safe will depend on the efficacy of the screens between the singers and possibly on their age and general health rather than on the electronics. I'm no virologist, but my common sense tells me it shouldn't take much to at least make it less dangerous than the average Dutch supermarket.
 
People always risk their lives to sing together. They usually need to cross a street or two to reach the rehearsal room, so there is always the risk of being run down by a car. It is really the magnitude of the risk that matters - which I can't judge very well, because I'm not a virologist and Felix hasn't specified what he will put in between the singers. Hopefully the local health authorities can advice him on that.
 
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