Wireless System Questions

[TimMc]

I've worked theatre with both the 160's and the AT PZMs, and I find that they're passable for recording, but unless your facility has zero resonances, you're going to be pretty hard pressed to get enough GBF for reinforcement.

I've gotten +6dB over ambient, and that's enough of a difference to be a genuine help. Not gonna mix the next Hamilton that way, but for community/school theater it can be useful.

I mixed a private school speech/drama conference (think: Thespian conference for private schools). It was 100% zone mixing with hanging mics and foot mics. The trick was to duck by -20dB the inputs not in use, so that the mic(s) nearest the dialog-producing actors could be turned up. The results were much better than the teachers/directors expected, many having tried area mics and had failed. I had several questions about what mics I used - but the real magic was between my ears and fingertips. Amazing what (was then) 30 years of mixing and professional sound reinforcement experience can do for a student show.

 

[Jay Ashworth]

I've gotten +6dB over ambient, and that's enough of a difference to be a genuine help. Not gonna mix the next Hamilton that way, but for community/school theater it can be useful.

I mixed a private school speech/drama conference (think: Thespian conference for private schools). It was 100% zone mixing with hanging mics and foot mics. The trick was to duck by -20dB the inputs not in use, so that the mic(s) nearest the dialog-producing actors could be turned up. The results were much better than the teachers/directors expected, many having tried area mics and had failed. I had several questions about what mics I used - but the real magic was between my ears and fingertips. Amazing what (was then) 30 years of mixing and professional sound reinforcement experience can do for a student show.

Yeah; I've done a community theatre with 3 -160's and 4 hanging lavs, and... eh, it was ok.

The civilians were happy with it, but I wasn't. That's always the way, though, no?

But certainly you have to line-mix it, yes.

 

[Chont]

So the summer season came to a close. The second headline show of the summer season had its moments. I convinced the exec to buy new microphones since the director wanted to use as many mics as possible and I wanted to eliminate as many points of failure as possible. When they arrived mid tech week, I offered to take the mics and number and date them with a p-touch so we could keep track of when they were bought and track issues. He told me he already had the intern label the bags. I tried to explain that no one is going to make sure the same mics end up in the same bag but I got the sense I was over stepping my boundaries and gave up. I was asked to be there for tech week and was already sensing it was going to be an aggregating experience.

The director had his son running the board for this one and there isn't enough room in the booth for a 3rd person so I was sitting just outside the booth during the tech runs for help if needed. Right at the start of the show, the main character is wheeled out on a platform wrapped in Christmas lights and the RF meter on receiver for her mic dropped to zero. The kid panics and started pushing buttons and turning knobs. I poked my head in and told him the receiver is getting nothing from her transmitter so no amount of button pushing and knob turning on the mixer is going to help. As soon as she steps off the platform BOOM! signal is back but he had the preamp, fader an EQs maxed now and it nearly took our heads off. The Overhead mics would have been perfect for this show because even though they were hung a little high, they were in a good spot to pick up the ensemble up on the platforms and worked really well earlier in the week before they added the lav mics. Now with the show at full volume and the wig mics added, the kid wasn't getting the concept of when to bring them in and when to cut them and how to keep them below the feedback threshold. The exec director told me at intermission to remove them from the board because "overhead mics are not compatible with wig mics"... uhh ok. I tried to make the case that the person at the board just needs to pay attention and use them when it makes sense but he wasn't having it and its his son so lost that battle. After the run the music director asked me where the overheads were because they were working well and I explained to him the situation and he just rolled his eyes. Oh well.

The replacement mics definitely helped. I had to kind of step away after tech week for my own sanity and advised them to rescan the receivers every show day, but they didn't take that advice. There were a couple of matinees that were a debacle so they asked me to help rescan them for the evening show which made all the difference... you'd think they would have done that the following weekend but didn't. I still think they are in dire need of an overhaul of their audio system because its hurting their reputation. Rumor has it there's some grant money coming but they will be putting it towards other things.

we shall see.

 

[Jay Ashworth]

RUN AWAY!

[ Network professionals work with the ISO 7-layer networking stack, from 1-Physical to 7-Application.

The running inside joke is that there are three more layers:

8-People
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which control how things work... ]

 

[Chont]

pardon the bump...

I got asked to help out for the show that's running now. I was able to put a couple of their old Sennheisers into the fold to see how they performed compared to their newer system. As expected, the Sennheisers were problem free.

I watched the Creative Audio receiver for the entire show to see if I could notice any patterns or changes to the display when the static appeared and there seems to be a few issues going on. The mic cable issue is now manageable with new mics and being more vigilant about how things are attached and secured to the actors. However, during the show, I noticed there was some general noise/static in the noise floor which hopefully I can address this week by increasing the gain on the transmitter? There was also some increased static in a few of the mics that when audible, the antenna symbol on the receiver display would be bouncing between the A and B antennas. I'm still trying to learn this stuff but from my research it seems like this could be "multipath interference". What was odd was on a couple of the mics, the interference would be present whenever the receiver bounced on the A antenna but for other mics, the noise would surface whenever those mics bounced to the B antenna.

Any thing I can do to help with the Antenna bouncing? Also the transmitters can be switched from -5 to 10mW power. Is there an ideal setting for this? Receiver is about 40 feet from the stage.

thanks as always.

 

[themuzicman]

I noticed there was some general noise/static in the noise floor which hopefully I can address this week by increasing the gain on the transmitter?

Noise/Static in the noise floor of the audio signal? Increasing transmission power of the radio signal is only going to hide problems, not solve them. Have you coordinated your transmitters frequencies to make sure they are not on top of any active TV stations or interfering with each other?

pardon the bump...
There was also some increased static in a few of the mics that when audible, the antenna symbol on the receiver display would be bouncing between the A and B antennas. I'm still trying to learn this stuff but from my research it seems like this could be "multipath interference". What was odd was on a couple of the mics, the interference would be present whenever the receiver bounced on the A antenna but for other mics, the noise would surface whenever those mics bounced to the B antenna.

Any thing I can do to help with the Antenna bouncing? Also the transmitters can be switched from -5 to 10mW power. Is there an ideal setting for this? Receiver is about 40 feet from the stage.

Antenna bouncing isn't a sign of multipath interference, you run 2 antennas for antenna diversity - if you are running remote antennas hopefully you are running cables matched for line-length so your diversity reception is true. The receivers will bounce to whatever antenna is seeing the most signal and capture on to that. Antenna bouncing is a feature, not a bug. It's only a bug if you lose signal completely when it bounces to an antenna which is usually a sign of something bad in the RF receive signal chain.

As for power, you want to be using the lowest usable power setting, I'd say you need to coordinate your frequencies to get clear of interference first, and then look at power second based on a good walk of new and clean frequencies.

 

[Chont]

Noise/Static in the noise floor of the audio signal? Increasing transmission power of the radio signal is only going to hide problems, not solve them. Have you coordinated your transmitters frequencies to make sure they are not on top of any active TV stations or interfering with each other?



Antenna bouncing isn't a sign of multipath interference, you run 2 antennas for antenna diversity - if you are running remote antennas hopefully you are running cables matched for line-length so your diversity reception is true. The receivers will bounce to whatever antenna is seeing the most signal and capture on to that. Antenna bouncing is a feature, not a bug. It's only a bug if you lose signal completely when it bounces to an antenna which is usually a sign of something bad in the RF receive signal chain.

As for power, you want to be using the lowest usable power setting, I'd say you need to coordinate your frequencies to get clear of interference first, and then look at power second based on a good walk of new and clean frequencies.

Thanks for the reply.

I have not I was kinda thrown into helping this theater out and the guy that installed the system came by over the summer and showed me to do a rescan for open frequencies on the receiver an sync the transmitters. Every thing is contained In a small rack on the balcony outside the control booth. They have a Creative Audio 8 Channel receiver with 4 whip antennas on the back. No one seems to know anything about how to operate it so since I have audio experience working in studios and audio post I've kind of been nominated to be the guy. I'm determined to wrap my head around this so we can have shows with good audio but I'll be the first to admit... This is new territory for me. The Mixing board in the booth is organized now though.

looking at Wireless workbench tutorials now. Should we NOT be rescanning new frequencies on the receiver and rather just finding open ones in our area based on what wireless workbench finds and sticking with those?

 

[themuzicman]

looking at Wireless workbench tutorials now. Should we NOT be rescanning new frequencies on the receiver and rather just finding open ones in our area based on what wireless workbench finds and sticking with those?

If you're rescanning you need every transmitter OFF so the receivers can see TV stations, I don't know if WSM can generate frequencies for third party systems. If you're using Workbench just build profiles for your gear and you'll most likely be fine. I don't typically use Workbench, and instead use IAS or Soundbase - the last few times I've used Workbench in major metropolitan areas to compare results against my dedicated software it hasn't alerted me to Public Safety channels which has been a little problematic however I'm sure as long as you build profiles for your Creative Audio microphones you should be able to get clean frequencies for your use.

 

[Chont]

If you're rescanning you need every transmitter OFF so the receivers can see TV stations, I don't know if WSM can generate frequencies for third party systems. If you're using Workbench just build profiles for your gear and you'll most likely be fine. I don't typically use Workbench, and instead use IAS or Soundbase - the last few times I've used Workbench in major metropolitan areas to compare results against my dedicated software it hasn't alerted me to Public Safety channels which has been a little problematic however I'm sure as long as you build profiles for your Creative Audio microphones you should be able to get clean frequencies for your use.

Thank you so much for your reply. I checked these out and using the Soundbase app. Was able to get a picture of what the area around the theater looks like. I'm still trying to wrap my head around this but looks like the Mics that were giving me problems are close to occupied TV stations in the area. Does it Make sense to try and manually set the frequencies further away from those bands or scan them until it lands on one in the wide gap and then just keep everything set to those if they are clean? I do keep all transmitters off when I do the scan but I leave each transmitter on after I sync it to the receiver. Should I turn them off after they are sync'd? Thank you so much again... I apologize for the basic questions.

Mic 1 - 500.400 ch.052 - Static when bouncing to Antenna A

Mic 2 - 519.600 ch.048 - Not In Use

Mic 3 - 505.600 ch.078 - Static when bouncing to Antenna A - This mic had worst static

Mic 4 - 519.200 ch.046 - No Issues

Mic 5 - 490.000 ch.000 - No issues

Mic 6 - 520.400 ch.052 - Static when bouncing to Antenna B

Mic 7 - 493.200 ch.015 - Not In Use

Mic 8 - 518.600 ch.043 - Static when bouncing to Antenna B

 

[TimMc]

Let Soundbase pick the frequencies.

 

[Chont]

Let Soundbase pick the frequencies.

Makes sense thank you. Looks like our Receiver operates in the G band... I assume that is by chance when they bought it. Based on my scan here It's a drag they didn't get the unit in the H band.

 

[themuzicman]

Thank you so much for your reply. I checked these out and using the Soundbase app. Was able to get a picture of what the area around the theater looks like. I'm still trying to wrap my head around this but looks like the Mics that were giving me problems are close to occupied TV stations in the area. Does it Make sense to try and manually set the frequencies further away from those bands or scan them until it lands on one in the wide gap and then just keep everything set to those if they are clean? I do keep all transmitters off when I do the scan but I leave each transmitter on after I sync it to the receiver. Should I turn them off after they are sync'd? Thank you so much again... I apologize for the basic questions.

I wouldn't manually set frequencies, I would use Soundbase to generate IMD-less frequencies, and I would reference your scan visually for what works and what doesn't work.

That being said, I did run your frequencies for IMD and they appear clean.

Your scan + sync process is correct if you are going that route.

My only guess, based on your noting of which mics have issues with specific antennas is that there are internal issues with the antennas or antenna cabling. There isn't much to go by in regards to a spec sheet for your device - it just says 2 sets of antennas, which makes me think RF 1-4 share an antenna pair and RF 5-8 share an antenna pair. It looks like 1-4 have issues on one antenna and 5-8 have issues on another set. It could be as simple as a bad cable pass-thru, or a bent conductor on an antenna, but I feel like the answer is somewhere there.